Report of the Dutch-Mauritanian Project Banc D'arguin 1 9

Home , Arguin, Azores

Report of the Dutch-Mauritanian project Banc d'Arguin 1985-1986

edited by : Bruno J. Ens Theunis Piersma Wim J. Wolff Leo Zwarts

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RIJKSINSTITUUT VOOR NATUURBEHEER

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Pare National du Banc d'Arguin (PNBA)

Dutch Working Group for International Wader-and Waterfowl Research (WIWO

Research Institute for Nature Management (RIN)

Netherlands Institute for Sea Research (NIOZ)

BIBLIOTHEEK RIJKSINSTITUUT VOOR NATUURBEHEER Texel 1989 POSTBUS920 1 6800H B ARNHEM-NEDERLAND R.I.N.-RAPPORT Vr DEDICATED to thememor y of our respected friend

Ely ould Elemine WIWO Rapport 25

RIN-rapport 89/6

The WIWO report series intends to be a regular medium by which occasional reports of ornithological expedition or journeys can be published. In this way regular distribution and availability are guaranteed. Large quality differences are accepted, since the authors remain responsible.

The RIN reports are amediu m to report on research projects by RIN collaborators. The RIN reports have a limited distribution, mainly within The Netherlands.

This report can be ordered by paying Dfl. 35,-o n either: -postal giro account 2.666.009 or toAB N bank account 57.02.16.613 of Stichting WIWO,Ewijk ,Th e Netherlands, or -postal giro account 51 60 6 48 of Rijksinstituut voor Natuurbeheer,Leersum , The Netherlands. Postage is included in the price.

This report is also to be published inFrench .

-"v *-»~ v >• -\ COLOPHON V

Typing :Michael a Scholl Figures :Wiebere n Planting Bird drawings: Jos Zwarts J CONTENTS

1 INTRODUCTION 7

2 ORGANISATIONAN D ITINERARY 12

3 METEOROLOGICALMEASUREMENT S 16

4 TIDEMEASUREMENT S 43

5 WADERCOUNT S 57

6 VISIBLEMIGRATIO N 68

7 WADERCATCHE S 77 7.1 Methodology 77 7.2 Capture totals 85 7.3 Recoveriesan dresighting s 87

8 WADERBOD YCOMPOSITIO NANALYSI S 93

9 NOTEO NGULL SAN DTERN S 104

10 SYSTEMATICLIS TO FBIRD SAN DMAMMAL SOBSERVE D 111

11 TIMEBUDGE TO FWADER S 196

12 WADERENERGETIC S 199 12.1 Heat stresso nth eroos t 199 12.2 Saltstres scage dbird s 200 12.3 Energeticcos to fweigh tgai n 201

13 FORAGINGOYSTERCATCHER SO NTH EBAN CD'ARGUI N 203

14 FEEDINGBEHAVIOU R OFWHIMBRE LAN DANTI-PREDATO R 205 BEHAVIOURO FIT SMAI NPRE YTH EFIDDLE R CRAB (UCATANGERI ) 15 LISTO FMARIN EPHANEROGAMS ,MOLLUSCS ,POLYCHAETE S 208 ANDCRUSTACE AOBSERVE DALIVE DA TTH EBAN CD'ARGUI NI N 1985AN D 1986

16 DISTRIBUTION,BIOMASS ,RECRUITMEN TAN DPRODUCTIVIT Y 220 OFANADAR ASENILI S- ABSTRAC T

17 FISHESAN DSHRIMP SO NTH ETIDA LFLAT SA TTH E 222 BANCD'ARGUI N

18 RECOMMENDATIONS FORTH EMANAGEMEN TO FTH E 228 PARCNATIONA LD UBAN CD'ARGUI N

19 REFERENCES 229

kPPENDI XI 236

WADERBIOMETRIC S 236 1 Oystercatcher 236 2 Avocet 239 3 RingedPlove r 240 4 KentishPlove r 250 5 GreyPlove r 257 6 Knot 264 7 Sanderling 276 8 LittleStin t 284 9 CurlewSandpipe r 290 10 Dunlin 300 11 Bar-tailed Godwit 315 12 Whimbrel 320 13 Redshank 323 14 Turnstone 327

APPENDIX II 335 Maps 335 INTRODUCTION

About 7millio ncoasta lwader s (.Limicoles,Charadrii )migrat eannuall y betweenvas tarcti can d subarcticbreedin garea san d temperatean d tropicalwinte rquarter sscattere d along theeaster n shoreso fth e AtlanticOcean .Afte ra shor tbreedin g seasoni nth earcti c tundraso fN E Canada,Greenland ,Iceland ,Scandinavi a andth enorther n partso fth e USSR thesebird sarriv ea t thetida lflat so fth eWadde nSe aan dth e estuaries ofGrea tBritai ni nlat esummer .Afte rmoultin g theirfeathers , somewader ssta y theret owinte rbu tman yother smigrat efurthe r southt o spend thewinte r inS WEurope ,West-Africa ,an deve nsouther nAfrica .A t leasthal fo f thecoasta lwader susin g theEas tAtlanti cflywa y spendth e winteri nthes eAfrica nwinte r quarters (Piersmae tal . 1987). About 1980i tbecam eclea rtha t thetida lflat so fth eBan cd'Argui n (Fig. 1)i nMauritani awer eon eo fth emos t importantwinterin garea s along theEas tAtlanti c flyway.Ove r 2millio nwader swer ecounte di n that regioni nwinte r (Trotignon 1980,Altenbur g etal . 1982).Remarkabl y enoughfoo dcondition so nth eBan cd'Argui nappeare d tob emargina l (Altenburge tal .1982) .Roug hcalculation sbase d ondat acollecte d in February 1980showe d that thetota lamoun to ffoo dpresen twoul db e consumedwithi ntw omonth si fn oregrowt ho rresettlemen t offoo d organismswoul d occur.Althoug hsom eregrowt h islikel yt ooccur ,i t remains tob esee nho wthes ebird sar eabl et opu to nsufficien t fati n earlysprin g forthei rnorthwar dmigration . Thisquestio n- ho wbird sar eabl et ostar t theirsprin gmigratio n fromth eBan cd'Argui n ingoo dconditio n- forme d thecentra l themeo f theDutch-Mauritania nprojec t "Bancd'Argui n1985-86" . Toanswe rthi squestio nw ehav et okno who wmuc hfoo di savailabl ei n springan despeciall y howmuc hextr a food isproduce d inthi speriod . Secondlyw enee d tokno who wmuc hfoo d isrequire d byth ebird san dwha t isthei rextr anee d topu to nsufficien t fatfo r thesprin gmigration . Finallyw ehav et okno wwhe nth ebird spu to nthi sfat ,whe n theyleav e andwhic h stagingarea s theyma yo rhav et ouse . Thisi sver y shortly theprogramm e of theprojec t "Banc d'Arguin 1985-86"develope d byth eWorkin gGrou pfo rInternationa lWader -an d WaterfowlResearc h (WIWO),th eResearc h Institutefo rNatur eManagemen t (RIN)an d theNetherland s Institute forSe aResearc h (NIOZ).Du et o shortage of funds itwa sno tpossibl e tocarr you t theentir e programme

0 10 20 30 40k m

Figure 1.1.Locatio n in Africa and general map of the Banc d'Arguin, Mauritania. in 1985,a s conceived originally. Because the international Wader Study Group had planned an international project to study themovement s of waders during spring migration by means of birds with colour marks in the spring of 1985,i t was decided to carry out only that part of the project "Banc d'Arguin 1985-86"whic h supported the international project and to postpone the remainder of the programme to 1986. From the start of the project it was envisaged thatMauritania n counterparts would take part in the project.Consultatio n with the Mauritanian authorities resulted in a joint Dutch-Mauritanian project in which on theMauritania n side the Pare National du Banc d'Arguin and the Directorate for Nature Protection of theMinistr y of Rural Development took part.

The aims of the project "Banc d'Arguin 1985-86"wer e inmor e detail:

1. Studies on spring migration of waders in relation to feeding condition.

This part of the programme had to lead toa detailed analysis of the origin ofwader s at the Banc d'Arguin and the timing, patterning and extent of wader migrations from and through Banc d'Arguin in spring,an d toa n apraisal of the physical changes in the birds themselves which allow them these movements. Information on the fate of the birds after they have left the Banc d'Arguin, had to be gained as a result of these local studies. The research programme to reach these aims consisted of three parts,viz .descriptio n of arrival and departure ofwaders ; description of the changes in physical condition of the birds before departure; and description of the routes taken by the waders to reach the breeding grounds and the location of these breeding areas.

2. Studies on the biomass and productivity of the benthic fauna of the tidal flats.

This involved in the first place a general survey of the benthic fauna of the Banc d'Arguin in order to obtain a reference value for the biomass of the entire area. Secondly, growth and production rates of selected invertebrates had to bemeasure d in order to obtain an estimate of benthic productivity. This had to be compared with measurements on biomassremova lb ypredator san d othercauses ,carrie d outb ymean so f exclosures.Thirdly ,i tha d tob einvestigate d whetherinvertebrate san d smallfis hmigrat ewit h thetide sbetwee n tidalchannel san d flats,thu s forminga nadditiona l sourceo ffoo d forwader swhic hescap e theusua l methodso flo wtid esampling .

3.Studie s onth efeedin gbehaviou ran decolog yo fwaders .

Inth efirs tplac ei tha d tob edetermine d fora sman yspecie so fwader s aspossibl ewha t typean d sizeo fpre y isobtained .Secondly ,fo ron eo r a fewspecie s thefoo dconsumptio n inth efiel dha d tob equantifie di n ordert oestimat e theenergeti c requirement ofth especie s (dailyenerg y intake).Thi swa scombine d withdat ao nlow-tid efeedin gdensitie so f waders inorde r toarriv ea ta nestimat e forth econsumptio na tth e entire Bancd'Arguin .Thirdly ,th eextr afoo d intakeneede d toaccumulat e migratory fat,ha d tob edetermine d forbird s incaptivity .Fourthly ,i t had tob einvestigate d inwil d birdswhethe rfa taccumulatio n priort o migrationi sdu et oa nincreas ei nforagin g efforto ra nincreas ei n availablefood .

ACKNOWLEDGEMENTS

Theprojec twa ssupporte d financiallyby : - theCommissio n ofth eEuropea nCommunitie s (Brussels); theNationa lGeographi c Society (Washington); theNetherland sMinistr y ofAgricultur ean dFisherie s (TheHague) ; - theShel lInternational eResearc hMi j(Th eHague) ; - thePrin sBernhar d Fund (Amsterdam); theSociet yfo rth eProtectio n ofNatur eMonument s inth eNetherland s ("Natuurmonumenten")('s-Graveland) ; - theNetherlands 'Stat eForestr y Service ("Staatsbosbeheer")(Utrecht) ; theFun d forResearc hfo rNatur eProtectio n (FONA)(Arnhem) ; theBritis hOrnithologica lUnio n (London); - theBachien eFoundatio n (Leiden).

Thehel po f theNetherlands 'Societ yfo rth eProtectio no fth eWadde n Sea (Harlingen)i nprefinancin g theprojec twa sinvaluable .

10 Thesuppor t ofth eMauritania nauthoritie s isgratefull yacknowledged . Weshoul d like tomentio nMr .Gabrie lHatti ,Advise r ofth eSecretar y Generalo f thePresident ,Mr .Hady aAmado uKane ,Directo r ofth e Directorate forNatur e Protection of theMinistr y ofRura lDevelopmen ti n 1985an dDirecto r of thePar eNationa ld uBan cd'Argui ni n 1986,Mr .Da h ouldCheikh ,Governo r ofNouadhibou ,Mr .S yZakary adi t SyKao , Vice-Governor ofNouadhibou ,Mr .Mahmou d ouldMerzoug ,Directo r ofth e Directorate forNatur eProtectio ni n 1986,an dMr .Abderrahman eTouré , Director of thePar eNationa l duBan cd'Argui ni n 1985.W eals olik et o thankJos éLui sd eTorregros aGarci ao fth efir mICOD ,th ecollaborator s of thePar eNationa ld uBan cd'Arguin ,th eCampredo n family,th eGermai n family,th e"Cooperatio nd eTimiris" ,an d theinhabitant s ofIoui kan d othervillage sa tth eBan cd'Arguin . Material supportwa sgive nb yth eRingin gOffic eo fth eCRBP O(Musé e d'HistoireNaturelle )i nParis ,th eBir dMigratio nCentr e ("Vogeltrekstation")i nHeteren ,th eWas hWade rRingin gGroup ,th eRoya l NetherlandsMeteorologica l Institute (KNMI),th eNetherlands ' Rijkswaterstaat,th eZoologica lLaborator y ofth eUniversit yo f Groningen,th eIJsselmee rPolde rDevelopmen tAuthorit y (RIJP)an d numerous relativesan dfriends . Aspecia lwor d ofthan kmus tg ot oth eman ykee nfieldworker swh o happened tospo twader scolour-marke d duringou rexpedition ,elsewher ei n theworld .Th eresighting s of thesebird shav econtribute d greatly toou r knowledge ofth emigrator yroutes .Th ecolour-markin g registrationswer e ablyadministere d byChri sThoma san dDr .Hecto rGalbrait h ofth eWade r StudyGrou p- Colour-markin g register. During theanalysi so fth edat acollecte d atth eBan cd'Argui nw ewer e supported byDr .Ges aHartmann-Schröde r (Hamburg),Dr .G.C .Cadé e (Texel),Rinu sManuel s (Texel),Miche lBinsberge n (Texel),Drs .J.B .va n Biezen (Arnhem),Nienk eBloksm a (Groningen),He wPrendergas t (U.K.),Nic k C.Davidso n (Peterborough),Pete rProkosc h (Husum),Deni sBredi n (Rochefort),Joo pJukem a (Oosterbierum)an dman yother s.. . Toal lw eow eth esucces so fth eproject !

11 ORGANISATION AND ITINERARY

Theprojec twa sconceive d asa join tDutch-Mauritania nproject .Th e Mauritaniansid ewa srepresente d byth ePar eNationa ld uBan cd'Argui n (PNBA)a tNouadhibo uan d theDirectorat e forNatur eProtectio n (DPN)o f theMinistr y ofRura lDevelopmen ta tNouakchott . Mauritanian participants inth eprojec twere :

ElHassan eoul dMohamme d elAbd ,guar do fth eBiologica lStatio na t Iouik(PNB A 1986); PierreCampredon ,biologis twit h thePNB A(1985 ,1986) ; AbouGueye ,hea d ofth eScientifi cDepartmen t ofth ePNB A(1985 , 1986); Cheikhnaoul dM'Barè ,hea do f theDept .o fHuntin gan dFaun ao fDP N (1985);

MohammedM'Barec koul d Soueilemo fth eCentr eNationa ld eRecherche s Océanographiques etde sPêche s (1985)len dhi ssuppor tdurin ga visi to f awee k toou rbas ecam pa tIouik . At theDutc h sideth eprojec twa scarrie d outb yth eWorkin gGrou pfo r InternationalWader -an dWaterfow lResearc h (WIWO),a numbrell a organisation forpeopl eo fdifferen taffiliations ,th eResearc h Institute forNatur eManagemen t (RIN)a tTexe lan d theNetherlands 'Institut efo r SeaResearc h (NIOZ)a tTexel . Dutchparticipant s inth eprojec twere :

Nellyva nBrederode :ornithologis tan dmedica ld c ora tGroninge n University (WIWO 1985); Anne-Marie Blomert:biologis ta tGroninge nUniversit y (WIWO 1986); SjoerdDirksen :biologis ta tGroninge rUniversit y (WIWO 1986); PietDuiven :biologica lassistan ta tNIO Z (1985,1986) ; BrunoEns :biologis ta tGroninge nUniversit y (WIWO 1985); PeterEsselink :biologis ta tGroninge nUniversit y (WIWO 1986); MarkFletcher :biologis ta tth eMinistr yo fAgriculture ,Foo dan d Fisheries,Grea tBritai n (WIWO 1985);

12 Roelof Hupkes:biologis ta tGroninge nUniversit y (WIWO 1986) Janva nd eKam :photographe r (WIWO 1985,1986) ; MarcelKersten :biologis ta tGroninge nUniversit y (WIWO 1985); MarcelKlaassen :graduat estuden ta tGroninge nUniversit y (WIWO 1986); AndréMeijboom :biologica lassistan ta tRI N (1986); GerardMoerland :graduat estuden ta tRI N (1986); TheunisPiersma :biologis ta tGroninge nUniversit y (WIWO 1985); CorSmit :biologis ta tRI N(1985 ,1986) ; Tomva nSpanje :ornithologis tan dgenera lcoordinato ro f theprojec t (WIWO1985 ,1986) ; KeesSwennen :biologis ta tNIO Z (1986); Jaapd eVlas :biologis ta tth eNetherland sMinistr y ofAgricultur ean d Fisheries (RIN 1986); WimWolff :biologis ta tRI N (1986); KoosZegers :biologica lassisten ta tRI N (1986); LeoZwarts :biologis ta tIJsselmee rPolder sDevelopmen tAuthorit y (WIWO 1986).

Theexpeditio noffic ean dsecretaria twer ehel db yRIN ,wher eMr s Veronicad eWi tspen tmuc h timeo npreparatio nan dcoordinatio nunti l 1986, whereafterMs .Michael a Schollwa sinvolve d inremainin gwork .RI N alsomad eth eservice so fit sworksho pavailable . Mr. EkkoSmit han dMr .Meint eEngelmoe r (WIWO)handle d allfinancia l matters,wherea sDr .Gerar d Boere (WIWO)acte da sa genera ladviser .

Itinerary

9-23 December 1984 : Tomva nSpanje ,genera lcoordinato r ofth e project paysa preparator yvisi t toMauritania . 10Marc h 1985 :Arriva lo fNell yva nBrederode ,Pie tDuiven , BrunoEns ,Mar kFletcher ,Ja nva nd eKam , Cheikhna ouldM'Barê ,Theuni sPiersma ,Co rSmi t andTo mva nSpanj ei nNouadhibou . 11-19 March 1985 :Preparation s forsta ya tIoui ki nNouadhibou . 20- 2 1Marc h 1985 :Voyag e toIoui kb ytw ofishin g boatsan don e Landrover;th enigh twa sspen ta tTe nAlloul .

13 22Marc h- Stayi nIouik ,wher eAbo uGuey ewa salread y 30Apri l 1985 present. 20apri l 1985 Departure ofMar kFletcher . 27apri l 1985 Departureo fNell yva nBrederode ,Pie tDuive nan d MarcelKersten . 1- 5 Ma y 1985 Returnvoyag et oNouadhibou ;arrangement sfo r departure fromNouadhibo uan ddepartur eo fal l project participantsexcep tAbo uGuey ean dTo m vanSpanje . 13-1 4Ma y198 5 Returnvoyag eo fTo mva nSpanje . November 1985 Visit ofAbo uGuey ean dCheikhn aoul dM'Bar êt o theNetherland sfo rtrainin gi ndat aanalysis .

19Januar y 1986 Arrivalo fTo mva nSpanje ,genera lcoordinato ro f theproject ,i nNouadhibou . 2Februar y 1986 Arrivalo fAnne-Mari eBlomert ,Sjoer dDirksen , PeterEsselink ,Roelo fHupkes ,Ja nva nd eKam , MarcelKlaassen ,Andr éMeijboom ,Co rSmit ,Kee s Swennene nWi mWolf f inNouadhibou .Introductio n ofAbo uGueye ,Mauritania ncounterpart . 3-4 February 1986 Unloading ofequipmen tfro mcontainer san d preparations forsta ya tIouik . 5-6 February 1986 Voyage toIoui kb ythre efishin gvessels . 6-9 February 1986 Welcome byE lHassan eoul dMohamme d elAbd ,on e ofth eMauritania ncounterparts .Constructio no f campa tIouik .Arriva lo fPierr eCampredon . 6Februar y 1986 Departureo fMarce lKlaassen . 11Februar y 1986 Arrivalo fLe oZwarts . 21-27Februar y198 6 Fieldworki nth esouther npar to fth ePar e Nationald uBan cd'Argui nb yAbo uGueye ,Pete r Esselink,Ja nva nd eKam ,Andr éMeijboo man dWi m Wolff. 2-3 March198 6 Firstchang eo fpersonnel .Pete rEsselink ,Ja n vand eKam ,Co rSmit ,Kee sSwenne nan dWi mWolf f leavean dPie tDuiven ,Marce lKlaassen ,Gerar d Moerland andJaa pd eVla sarrive .

14 30- 3 1Marc h198 6 Secondchang eo fpersonnel .Sjoer dDirksen ,Andr e Meijbooman dJaa pd eVla sleav ean d CorSmit ,Wi m Wolffan dKoo sZeger sarrive . 9Apri l198 6 Departure ofLe oZwarts . Preparations fordeparture .Dismantlin g ofth e 21- 2 3Apri l198 6 campa tIouik . Returnvoyag e toNouadhibo ub ytw oloca lfishin g 24- 2 5Apri l198 6 vessels.Th enigh twa sspen ta tth eli ed'Arguin . Loadingo fequipmen t intotranspor tcontainer . 26- 2 7Apri l 1986 Finalarrangement san dcourtes yvisit si n Nouadhibou. 28Apri l 1986 Departure ofal lremainin gDutc hparticipant s except forPie tDuive nan dTo mva nSpanje . 1Ma y 1986 Departureo fPie tDuiven . 15Ma y198 6 Conclusiono fth eprojec t inMauritani a byTo m vanSpanje . 9 September- 4Octobe r198 6 Visit ofAbo uGuey ean dMr .Mamado uAlassan eSai l toRI Na tTexe lfo rtrainin g indat aanalysis . 22-26Septembe r 1986 Visito fMr .Kan eHady at oth eNetherlands .

?ei

15 METEOROLOGICAL MEASUREME NTS

Cor J. Smit, Anne-Marie Blomert & Leo Zwarts 3.1 Introduction In order to measure the conditions birds encounter when staying at the Banc d'Arguin, registrations of the most important weather parameters were made. We used stamped equipment, set to our disposal by the Royal Netherlands Meteorological Institute (KNMI) at De Bilt, The Netherlands. The following measurements were taken: - temperature at 10 cm and 150 cm height; - atmospheric pressure;

Figure 3.1. The weather station at the Iouik camp, as it was used in 1985 and 1986. From left to right: the weather box at 150 cm, holding minimum and maximum thermometers, thermograph, barograph and hydrograph, the 10 cm thermometers stand, precipition meter and wind meter.

16 - relativehumidity ; -win d forcean ddirection ; -precipitation .

3.2 Methods Theset-u po f theIoui kweathe r stationi sshow n infigur e 3.1 Temperatureswer emeasure d under standard conditionsa t 10an d 150cm , usinga stan d andweathe rbo xrespectively . Inbot hsituation sth e equipmentwa sprotecte d againstdirec t radiationfro mth esun . Temperature registrationsa t 10c mwer emad eusin gminimu man dmaximu m thermometersallowin g fora naccurac yo f0. 1 C.Temperature sa t 150c m weremeasure d usingcomparabl e thermometersbu twer eals oregistere d continuouslywit ha Fues sthermograph .Registration so fth elatte r instrumentwer erea dever yhour ,wit ha naccurac yo fful ldegree s Celsius. Atmospheric pressurewa smeasure d continuously at 150c mheigh t ina standardweathe rbox ,usin ga Fues sbarograph .Registration swer erea d everyhou rwit ha naccurac y offul lmbar . Relativehumidit ywa smeasure d continuouslya t 150c mheigh t ina standard weatherbox ,usin ga Fues shygrograph .Registration swer erea d everyhou rwit ha naccurac yo fful l% . Windforcean ddirectio nwer emeasure d continuouslya tabou t 2m height,usin g aLambrech twin dmete ra ta sit eabou t 10m fro m thecamp . Asa resul t offavourabl ewin d directions,n oturbulenc e could occurdu e toth epresenc eo fth ecamp .Win ddirectio nwa sregistere d continuously too.Bot h typeso fregistration swer erea d everyhour .Win d directionwa s classified ason eou to f8 categorie s (W,NW ,N ,NE ,E ,SE ,S ,SW) . Precipitationwa smeasure d usinga standar d precipitationmete r ona stand.Du et osan dan ddus tstorm s themete rha d tob ecleane d regularly. Allinstrument ssustaine d thehars hclimati c situationa tth eBan c d'Arguini na goo dway .Som esligh tan dunimportan t failureswer edu et o inexperiencei nhandlin g theequipment .Afte rretur ni nth eNetherland s hourlymeasurement swer estore d intoth eVAX/VM Scompute r of theResearc h Institutefo rNatur eManagement .Result swer ecalculate d usingGensta t statistical programmes.Mos t resultswer eanalyze d intw oways : -a calculatio n ofmaximum ,mea nan dminimu mvalue sove r 24hours ,fo r thewhol eobservatio n perioda t theBan cd'Arguin .Mea nvalue swer e calculated usingal l 24hourl ydata ;

17 -a calculatio n ofmea nvalue s perhou rove rsevera l periods.Fo r198 5 thesewer e chosenmor eo rles sarbitrary .Period swer e 24March- 8April , 9-17 Aprilan d 18-29April .Fo r 1986mea nvalue swer ecalculate d for 10-day periods,excep t for thestar tan d theen do fth eobservatio n period. For severalmeteorologica l parameters attemptsar emad e tocompar eth e resultso f theregistration s at theIoui kcam pwit hdat afro mpermanen t registrationso fNouadhibo uAirport .Thes edat awer eliberall y seta tou r disposalb yMessrs .Ahmedo u0 .Abdalla han dGeorge sJosep h (Agencepou r laSécurit éd el aNavigatio nAérienn ee nAfriqu ee tà Madagasca r- ASECNA).

3.3Result s 3.3.1Temperatur e Figures 3.2 and 3.3 showmaximum ,mea nan dminimu m temperaturesfo rth e 1985an d 1986registratio nperiod s respectively.Figur e 3.2 showsa gradualbu tstrikin gdecreas e inmea n temperatures inth ecours eo fth e 1985season . Figure 3.4,showin gmea ntemperature sove r 3registratio nperiod si n 1985,demonstrate s thatth edecreas ei nmea nvalue si smainl ydu et oa dramaticdro pi ntemperature s between 9a.m .an d 7p.m .i nth esecon dan d third registrationperiod .Minimu mtemperatur evar ybetwee n 15C an d 20°C,bot ha t 10an d 150c mheight ,an d remainfairl y stablei nth e courseo ftime .Figure s 3.3,3. 5an d 3.6,showin g the 1986pattern , demonstrate agradua ldecreas e intemperature s inth eearl ypar to fth e registrationperiod ,agai na sa resul to fdroppin g temperaturesdurin g mid-day.Fro mearl yMarc honward sa slo wincreas e inmea n temperatures canb enoted ,especiall y duet oincreasin gminimu m temperatures.Fo r 1986 especially therelativel y lowminimu m temperatures inFebruar yar e striking. Acompariso no fmaximu man dminimu m temperaturesa t 10an d 150c m showstha tmaximu m levelsa t 10c mgenerall yexcee d thelevel smeasure d at 150c mb yu pt o5 C .Hig hgroun d temperatures aremainl ydu et o reflectiono fhea tfro mth esoil .Minimu m temperaturesa t 10c mgenerall y are only slightly under thosemeasure d at 150cm .

3.3.2Atmospheri c pressure Datao natmospheri c pressure for 1985showe d asystemati c difference

18 TEMPERATURE,°C

M MEAN TEMP. *.T -tso CM M AO 0.—* HIN. TE>4P. IN *C AT «CM I i O O MAX.. / I £ A MlW. TE-MP. IM t AT ISO« MAX „ « .

25/3 30/3 5/^ •JO/y 15/4 Äy^ 25/4 2S/4

Figure 3.2. Minimum and maximum temperatures for each day at 10an d 150 cm height and mean temperatures calculated over 24hourl y registrations at 150c m at the Iouik camp in 1985.

19 TEMPERAXÜCE, C X X HSAN TEMP. AT 1SO CM •---• MIN TIMP M *C AT 10CH O O MAX. „ „ ,. „ ß £ «N. TEMP. H t AT 160CM MAX ., „ ,, a

12/b 49/z «o* as/2 S/3 V¥3 18*9 20/3 2S/3 SO/3 5fr iO/n i&A 2o/H

Figure 3.3. Minimum and maximum temperatures for each day at 10an d 150 cm height and mean temperatures calculated over 24hourl y registrations at 150c m at the Iouik camp in 1986.

compared tothos ei n 1986an d tointernationa lweathe rmap s forth e198 5 observationperiod .Apparentl y thebarograp hwhic hwa suse dwa sno t functioning properly,possibl ya sa resul to fdamag edu et o transportationo fth eequipment .I tappeare d impossiblet ocorrec tfo r thesedifference s and forthi sreaso nth eresult shav eno tbee ninclude d inthi sreport .A sfa ra sth e 1985dat aca nb eused ,w ese erathe r regularfluctuation s inai rpressure ,howeve rwit ha ver yobviou s increasefro m 10-13Apri l 1985.Th e 1986data ,depicte d infigure s3.7 , 3.8an d 3.9 showa rathe rconstan tmea npressur eo fabou t 1017mbar , gradually decreasing towards theen do f theobservatio nperiod .Ther ei s a veryobviou sdi pi npressur e levelsfro m 22-28Februar y 1986,whic h

20 TEMPEftATZJRE, °C

9/^ - ly/u «s 24

•to 12 -I4 A6 18 2o 22 24 HOUR

Figure 3.4. Mean temperatures (°C)pe r hour over three observation periods at 150c m in 1985.

will bediscusse d latero ni nthi schapte r (3.5.1).Pressur e levelsi n thecours eo fth eda ysho wa highl y identicalpatter n foral ldecades , witha hig h pressure levelb y theen do fth emornin g and lowpressur eb y theen do fth eafternoon .Thi sdiurna l patterno fatmospheri c pressurei s comparable forth e situationme t inNorthwes tEurope ,throug hth e difference inhig han dlo wpressur e issomewha t larger,probabl ydu et o themor eintens eheatin gu po f theatmosphere .Thi sdiurna l patternha s little incommo nwit h theweathe r situation itself.I ti smainl ycause d by theattractin g forceso fsu nan dmoon .

21 -TCMPERACroQE *C

24 T^K» 1 -»«6

22 »=E» S ^«6

20-

1B>

Figure 3.5. Mean temperatures (°C)pe r hour over three decades (12 February-9March ) at 150c m in 1986. -TEMP02A.TURE: 'C

2.4 AW.W- ^ I906

->6

22. 24 WOCIR Figure 3.6. Mean temperatures (C )pe r hour over four decades (10 March-21 April) at 150c m in 1986.

22 PCETSSORE , MBAR

12/215/ 2 20/2 25/2«S/ 2 5/3 Figure 3.7. Minimum, mean and maximum data for atmospheric pressure (mbar)fo r each day in 1986.Mea n data were calculated over 24hourl y registrations.

1020

02. Ik VtOOR Figure 3.8. Mean data for atmospheric pressure (mbar)pe r hour over three decades (12 February-9 March) in 1986.

23 DRESSMRE, MBkM*

-I020

4018

4010

J 8 AO M 14 •«6 ie 22 £4 eo •J-IOÜR Figure 3.9. Mean data for atmospheric pressure (mbar)pe rhou r over four decades (10March-2 1 April)a t the Iouik camp in 1986.

RELATIVE wttjMtprry, %

Figure 3.10. Minimum, mean and maximum data for relative humidity (in X) for each day in 1985.Mea n data were calculated over 24hourl y registrations.

24 3.3.3 Relative humidity Relative humidity in the course of the season is depicted in figures 3.10 and 3.11. In both years the maximum relative humidity values go up to 90 or 100%,an d sometimes even exceed the latter value. The minimum humidity values vary greatly, on some days they even go up to 75%.A s a result the

RELATIVE vujMiorry, %

-100-

12/2 16/2 TO/2 2S/2 2B/2 5/3 10/3 -»5/3 TOß 2513 30iZ W iSA* 2o/

Figure 3.11. Minimum, mean and maximum data for relative humidity (in %) for each day in 1986.Mea n data were calculated over 24 hourly registrations.

25 RELATIVE waMiDiry %

^l2o-

-/oo

TH/3 - a AU as 60

S 10 12 14 16 18 20 22 24 J-tOüR Figure 3.12. Mean data for relative humidity (in %)pe r hour over three registration periods in 1985.

«ELATive i4UM>c»ry %

loo

22. 2*4 4-4CXÜR Figure 3.13. Mean data for relative humidity (in %)pe r hour over three decades (12 February-9 March)i n 1985.

26 RELATIVE WaMlD'TV %

HOO V\*BOl S. 1386 APtilL 2 L3S6

éo IL-) 1186 MAACV4 3 i«a6

8 HO H2 >iq 46 HS SO 22. 24 HOUR

Figure 3.14. Mean data for relative humidity (in %) per hour over four decades (10 March-21 April) in 1985.

mean relativehumidit yvalue s fluctuate ratherstrongl ya swell , generallybein g inth e40-80 %range .N oregula rpatter ni sdetectable , norca nobviou scorrelation sb efoun dwit hothe rmeteorologica l parameters.Ther eis ,however ,a ver yregula rdiurna lpattern ,depicte d infigure s3.12 ,3.1 3 and 3.14.Thes egraph ssho wrelativel yhig h humidity levels,especiall ya tnight .I nsom enight sthes ehig hlevel s lead tode wformation .Thes e 'wet'night sar ethos eexceedin g orcomin g closet o 100%relativ ehumidity ,show ni nfigure s3.1 0an d 3.11.Th e totalnumbe ro f 'wet'nights ,however ,ha sbee nconsiderabl y highertha n mayappea r fromfigure s 3.12 and 3.13.Th ereaso ni s that inth elatte r graphsw ear edealin gwit hmea nvalue sove r 7-16 hourlyvalues ,les s humid nightscausin g thehourl ymea nt odro pt oles s than100% .

27 3.3.4Win d forcean dwin ddirectio n Wind speeddat afo rth e198 5an d 1986observatio nperio dar eshow ni n figures 3.15-3.19.Figure s3.1 5an d 3.17demonstrat ea gradua lincreas e ofwin d speed inth ecours eo fth e198 5observatio nperiod .Especiall y therelativel yhig hwin d levelsa tnigh ti nth ethir d periodwer ea ver y seriousproble mfo rmis tne t catching.Ther ei sals oa nincreas ei nmea n wind speed inth e 1986season ,thoug hles sobviou sa scompare d to1985 . Averagewin d directions aredepicte d infigure s 3.20an d 3.21 showing thatprevailin gwind s inFebruar yan dearl yMarc hcom efro mth enorth , thoughn oconsisten t patterni nwin ddirection sca nb enoted .Fro mmi d Marchonward s the 1985an d 1986season sca nb ecompared .Bot hyear ssho w highlyconsisten t patterns inwin ddirections .Durin g thelas tMarc h decadeprevailin gwind sa tnigh tan di nth emornin gwer ecomin gfro mth e northeast.I nth eafternoo nan d theevenin gprevailin gwind scam efro m thenorth .Earl yApri lshow sa shif ttoward smor enortherl ydirections . Thisshif t continues overth ethir d period,showin gprevailin gnortheas t winds inth eafternoon .Northeas twind swer eonl yregistere d verybriefl y inth emorning .Ther ei sn oobviou scorrelatio nbetwee na certai nwin d speedan dwin ddirection . Figure 3.4 showsa remarkabl e increase intemperature s from8-1 0p.m . during thethir d registrationperio d in 1985.Thi sincreas eca nb e explained bya shif t inprevailin gwin ddirection sdurin g thisperio d from thenortheas t tonorth .Wind sfro mth enorthwes tarriv ea tth e registrationsit eafte rhavin gcrosse d therelativel ynarro wpeninsul a separating theBai ed'Aouati f fromth eAtlanti cOcean .Wind sfro mth e

northhav et ocros sa muc h larger stretcho fdesert .A sudde nshif ti n winddirectio naroun d 8p.m .therefor e startscarryin g relativelywar m wind fromth estil lrelativel ywar mdeser t toth ecamp .Othe r registration periodsals o showthi schang ei nwin ddirectio n thoughth e effects ontemperatur ear eles sstriking . Thedro pi nmaximu m temperaturesi n 1985(Fig .3.5 )seem st ob ehighl y correlatedwit hchange si nwin ddirectio ni nth ecours eo fth e observationperiod .I nth efirs tperio dhig htemperature swer eregistere d during themornin g andearl yafternoon .I nthes esituation s thewin dwa s blowingfro mth enortheas tunti labou t 1p.m. ,an deve nfro mth eeas ta t 10an d 11a.m. ,bringin gwar mwind sfro m theSahar a toth ecamp .A ssoo n asth ewin d changed toth enort h temperatures begant odro pgradually .I n thesecon d periodwind swer eblowin g fromth enortheas t only from5 unti l

28 WINEXSV^ETEP M /S

15.0

iOO-

24/3 3\P 11A» y* M 2?M A/Ç

Figure 3.15. Minimum,mea n and maximum wind speed (inm/s-lef t scale; Beaufort-right scale)fo r each day in 1985.Mea n datawer e calculated over 24hourl y registrations.

WlNDSPEED. M/S smètJEom,

12/2 2o/2 28/1 5/3 "to/3 -15/3 2o/3 25/3 3^3 S/*4 4&U HS/M QûM

Figure 3.16. Minimum, mean and maximum wind speed (inm/ s - left scale; Beaufort - right scale) for each day in 1986.Mea n data were calculated over 24hourl y registrations.

29 WINDSPEED, H/ S BEAat=ORT

Figure 3.17. Mean wind speed (inm/s-lef t scale;Beaufort-righ t scale) per hour over three registration periods in1985 .

WlMOSPEEO, M/S eEA

Figure 3.18. Mean wind speed (in m/s-left scale; Beaufort-right scale) per hour over three decades (12 February-9 March) in 1986.

30 VJINDSHEED, M/S ßfA^JFoRl

APo.it- a »«se A*»a«- •< i«w

6 MAACW ft IfiS*

-J U J L. -I I I !_ t\ 6

~~Figure 3.19. Mean wind speed (inm/s-lef t scale;Beaufort-righ t scale) per hour over four decades (10Marc h-2 1April )i n 1986.~~

~~AvEftAÄE *J\ND "DIRECTION 24/3 - G/<* '86~~

~~n/ 1 II llf llH'IM'HHFWWWIHtWMHfflHKIffyy w < J._, I i __1 Ï i k t i- _ -1. J-~~

~~e>Ai - W/<-\ '95 VIE. VJ _ J~ \„ \ / '~~

~~W i • > < I i ^ t,. < J 1 .....i 1~~

~~1S/-H - 29AJ 'SC MF N - nil i i -Ti1 1 il l' \T"r T»ww»wff V w~~

~~> • i_^ t L '.:. -t", • ••••T-* - h^ „...1 ._i i^J.JJ...i. 2 o. 6 81o12*(-(6«»fi2q MOdJß~~

~~Figure 3.20. Average wind directionpe rhou r over three registration period in 1985.~~

~~31 AVEQA&E V/lM O T>REO-tOM «8- 19/2 '*é 1* r > ., u / "X m w~~

~~~~*tv...... ».~~

~~2o - XI /3 '«~~

~~'t- Syi4 '86~~

~~UE *TTT^m lim mm* M TTTVTTT^Mr X, X_ y^ W~~

~~io_ü-./44 'S£ we N „ w^ V y~~

~~^u • ••* -< >•• 2 A 8 <> tö Vi 16 « 25 12 «1~~

~~Figure 3.21. Average wind direction perhou r over seven registration periods in1986 .~~

32 11 a.m.. No prevailing winds from the east were registered any more.A shift of wind direction at 3 p.m. towards the northwest resulted ina n almost immediate drop of temperatures.Durin g the third period in 1985 the wind changed towards the northwest already at 12a.m. , again resulting in a flow of relatively cool ocean air. For 1986mor e or less comparable correlations can be found. The diurnal pattern of changing humidity levels can often be correlated by the turning of the wind too.Win d from the northwest lead to the arrival of relatively wet air from the sea. However, not in all situations the turning of thewin d alone can explain the humidity increase. Wind direction, wind speed and large scale meteorological patterns (the weather situation at the ~~Atlantic Ocean)al l play a part. Chapter 3.5.1 describes the effects of the passage of high pressure areas, moving eastward north of Mauritania.~~

3.3.5 Precipitation In 1985 one shower was recorded during the whole observation period. The phenomenon occurred on 1AMarch , from 0.30-0.45 a.m., and yielded 0.2 mm rain. In 1986 there were two showers on 10 February, lasting from 6.15-7.00a.m . and 8.35-8.45 a.m., with some very light drizzle in the period in between. This extremely long lasting wet intermezzo, however, only yielded 0.1 mm of rain in total.Additionall y there was rainfall in the night of 21-22 April from 10.20 p.m. until 2.30 a.m. and from 4.30-4.35 a.m. Though the drops were large, they were falling far apart. Therefore the shower yielded no registrable amount of rain.

3.3.6 Dust and sand storms In this chapter a dust storm is defined as 'theai r filled with light dust, allowing for a visibility of over 1km' . During a sand storm larger particles are being transported onheav y winds, the visibility decreasing to less than 1km . Dust and sand storms are difficult to record systematically, mainly because there is no obvious transition between clean air and dust storm.Whe n sailing by ship along the Sahara,clos e to the coast,on e can always see a yellowish brown foglike dustlayer over the Sahara. In the camp a severe dust or sand storm not only severely hampered the visibility and the normal daily routine but also solar radiation. On 11Apri l 1985 for instance,afte r a day with a severe sand storm, maximum temperatures were reached as late as around 4-5 p.m. by

33 Table 3.1. Datao ndus tan dsan d stormsrecorde d inIoui ki n198 6an d information onwindspee d anddirectio ndurin g theseoccasions .Win dspee d data (inm/s )refe r toth ebeginnin gan d theen do fth edus tstor m period,togethe rwit h someintermediat evalues .

~~Date Time Windspee d Winddirectio n~~

February 18 10-14 11.5— > 5.3 east 21 11-13 9.6 —> 6.7 northeast 25 14-16 11.4— > 10.4 northwest 27 16-18 11.2— > 11.4 —> 10.8 northwest March 4/5 13-3 10.1— > 12.8 —> 10.5 north 6 12-15 9.1 —> 8.4 northeast 8 10-14 10.6— > 9.8 northeast 9 9-13 11.3— > 8.1 northeast 16/17 19-4 11.5— > 13.3 —> 10.3 northeast 18 8-12 11.9— > 12.9 —> 9.8 northeast 21 10-14 9.0— > 10.5 —> 8.8 east 22 9-11 9.7— > 6.4 northeast 24 16-17 7.8— > 7.5 northeast 25 16-20 10.7— > 11.7 northwest April 2 9-10 9.9 —> 10.5 —> 8.4 northeast 9 12-14 10.9-- >11. 3 north 12 14-16 12.1— > 10.7 northwest 17 16-17 11.8— > 11.3 northwest 18 9-11 12.4— > 13.2 —> 10.5 north 19 2-17 12.6— > 13.4 --> 8.0 northeast 20 7-8 11.0 north

thetim eth eamount so fsan dan d dust inth eai rgraduall ygo tsmaller . Lightdus tstorm soccu rrelativel y often,a sca nb esee nfro m table3.1 . Thistabl eonl yshow sdate sa twhic hdus t stormswer e recorded in1986 . In198 5onl y recordso fsan d stormswer emade .San d stormsoccu ra ta ratherlo wfrequency .I n198 5san d stormswer erecorde d on1 0Apri lan d 11April .Figur e3.1 5 showstha t sand storms in 1985wer erecorde do n dayswit ha maximu mforc eo f 15m/ san dwind sfro m thenortheast .O n otherday swit hwind sfro m thenortheas t (forexampl e 2-6April )win d forcewa sconsiderabl e smaller.O nday swit h relatively strongwind s (19-21Apri lan d 25-26April )withou t sand storms,prevailin gwin d directionswer enorthwes t ornorth .I n198 6les ssever esan d stormswer e recorded on4 Marc han d 19April .A compariso no ftabl e3. 1 andfigur e 3.16 shows thatdus t stormswer e recorded onday swit hmaximu mwin d

~~34 speedsove r8 m/ san da win ddirectio nfro meithe reas t ornortheast . Dayswit hdus t stormsan dwin d fromnort ho rnorthwes tal lha da maximu m wind speed over 11m/s .~~

3.4Registration sa t Iouikcompare d tothos efro mNouadhibo u Figure 3.22 showsmaximum ,mea nan dminimu m temperatures forNouadhibo u Airport from 1952t o 1985.Maximu man dminimu mtemperature sfo r February-April coincide ratherwel lwit h thosemeasure d at Iouik.Mea n temperatures inNouadhibou ,however ,ar esomewha t lower.A nexplanatio n mayb etha t theAtlanti cOcea nan d theBai ed eLévrie rar ealmos t completely encompassing thecity ,a sa resul to fwhic h theheatin g upo f theare a inth ecours eo fth eda yproceed sles srapidly .Especiall yi n thesecon d parto fMarc han dearl yApri l themornin gwind s inIoui kcom e fromth enortheast ,i.e .paralle l toth ecoas tan dpartl yfro mth e Sahara.Thes ewind scontribut e toa relativel y quickheatin gu po fth e

~~T^Mf^R*rz-n*E. t~~

~~A * 0~~

Figure 3.22. Mean minimum,mea n maximum and mean temperatures (calculated over eight daily measurements)a t Nouadhibou Airport in the course of the year.Minimu m and maximum values were calculated for 1953-82,mea n temperatures for 1961-85.Data :ASECNA , Exploitation Météorologique, Nouadhibou).

~~35 WINDSPEED, M/S ©EA^T^ORT~~

~~O fKAMO^A-SOWO~~

Figure 3.23. Maximum mean, mean and minimum mean wind speed (in m/s-left scale; Beaufort-right scale) per month at Nouadhibou Airport from 1961-85. For each month and year mean wind speed data were calculated. For this graph maximum and minimum values were selected and mean values calculated over the whole observation period. Data: ASECNA, Exploitation Météorologique, Nouadhibou. camp surroundings as soon as the sun rises. Increasing wind speeds as they were measured at Iouik, are in good agreement with an increase measured at Nouadhibou Airport. Figure 3.23 depicting mean values for 25 years, obviously shows increasing levels from December to June and decreasing levels from July-November, though the pattern of mean maximum and mean minimum levels is somewhat more complicated. Obviously there are rather large differences between years. Figure 3.24 shows wind directions at Nouadhibou Airport in the course of the year, the percentage of time without wind being highly limited. In January and February northeast winds are very frequent, from March to May there is a gradual increase of winds from the northwest. Winds from the north and northwest dominate highly in August, from September onwards northeast winds become more frequent again. This pattern is in good agreement with findings at the Banc d'Arguin.

~~36 JANUARY FERCtIAßY MARC« APRIL~~

~~3.6 -i.o~~

~~MA.7 3uuy AUfiÜftT~~

~~O 3 34~~

~~SEPTEMBER NOVEMBER PBCB-WER~~

~~<<4 35~~

Figure 3.24. Frequency ofwin d directions throughout theyea ra t Nouadhibou Airport.Th elengt h ofth earm s inth egraph s depictsth e percentage of time acertai n wind direction hasbee n measured, thewidt h of thearm s denotes wind speeds:narro w 1-6m/s ,moderat e 7-13m/s ,wid e 2 14m/s .Th efigur e inth ecentr e denotes thepercentag e of time with wind silence. Data: ASECNA, Exploitation Météorologique, Nouadhibou.

~~37 ~\\m mmmmmmm \mmmmmmmmmm~~

~~fll~~

~~o O~~

~~.:Ü!'M »~~

~~MH •—C 00 Ü 04 Ü~~

CO C O c (A 10 a •H 01 o 00 TJ •H HHHKIIII»»» QJ 3 4-» t. u et) iiiiniiiiiiiiuiniiiiiüiiiiüiiii^mie ft 4J u •rH •ni^ mmmmmmmmmmmm • r-i O a CCJ •H O. a U X IN o01 w <-* u •s 00 01 c »W < •H y-è z •rH u »O t/w3 £ •o to 4J < o ,, co cd l Fl u u 01 u co o ^00 o. o 38 10 u •»H T-t >£•> to T5 00 O , O G X> fH • 'in iiiiiiiiiiiiiiiiiiiiii mu HUI um um um um w\f».mmmmmm.

~~U T1 m, CO C Csl Ctl C. m• o •M >U . tu U CCI u c) 3 I 3 tu u, 00 Xi •H •>-H• 01 è *8 MÊMm miiiiiiiiiii iu mu mu m mmmwimmmmmmmmmmmmm mwmmmmmmmmmmmmmmmmmmmmm 2 °o O lo VO~~

38 Without theus eo fweathe rbaloon s iti salmos t impossible togathe r datao nwin ddirectio nan d speeda thighe raltitude .Fo r this reasonsuc h measurementshav eno tbee ncarrie d outa tIouik .I nNouadhibo uhowever , suchmeasurement shav e beendone - Figure 3.25 showsfrequenc y distributions ofwin d directionsa t4 altitude sa t 12a.m . for thesam e period asou robservation sa t Iouik.W eca nse ea gradua l shift inwin d directionsa thighe raltitudes .A ta lo wleve l (100-150m )wind s fromth e north-northwest,nort han dnorth-northeas t dominatehighly .A t 1800-2000 m,however ,apar tfro mwind sfro mnortherl ydirections ,ther ear erathe r frequentlywind s fromth esouthwes t toth enorthwest .I nApri l 1986wind s from thisdirection swer eeve ndominating !Unfortunatel y onlyver yfe w registrationswer ecarrie d outa t6 p.m. .Th efe wdat aavailabl eonl y allowu st oconclud e thata tlo waltitude swind sfro mth enorth-northwes t

~~MEMBER OF VMS 2* 24 22 to ii <|6 14 12 -~~

~~iO - a~~

~~é - <\- 2 run '//// m m '//// Î///2 3FMAHJJASONv//w, w, O~~

Figure 3.26. Mean number of days with light dust storms (visibility _>1 km)an d sand storms (visibility < 1km ,hatched )a t Nouadhibou Airport from 1954-1985.Data :ASECNA , Exploitation Météorologique, Nouadhibou.

39 andnort hwer ehighl ydominating .Ther ei son eobservatio n fromIoui k whichca nb ecompare d toNouadhibou .O n 11Apri l 1986a t9.3 0 a.m.,whe n thewin da tgroun d levelwa scomin g from thenortheast ,a thig haltitude s cloud veilswer ecomin gove rfro mth esoutheast .Balloo nregistration so n thesam eda yi nNouadhibo ua t 12a.m . showtha ta t 100m altitud eth e windwa scomin g fromth enorth-northeast ,an da t 1800m fro mth e south-southeast.A compariso no fwin ddirection sa t Iouikan drecording s madea tNouadhibo ua t 12a.m .a t 100m altitud e showstha tth edifferenc e inwin ddirection s betweenth etw ostation snormall yha sa maximu mo f 30.Ther ear en oindication sfo rsystemati cdifference si nwin d directions between thetw ostations .Thes edat asugges t thatwin d directions fromNouadhibo uAirpor tma yb euse d topredict ,wit hrathe r goodaccuracy ,th ewin ddirection sa tIouik . Figure 3.26depict s themea nnumbe ro fday spe rmont hwit hsan d storms,allowin g forles stha n 1k mvisibilit ya tNouadhibou .O naverag e insprin gan d summer 1-2day spe rmont hwit hsan d stormsca nb e registered thoughi nsom eyear sth enumbe rma yb ea shig ha s6 .Fro m September onwardssan dstorm sa tNouadhibo udecreas ei nnumber .Th esam e appliesfo rth emea nnumbe ro fday swit hdus ti nth eai rallowin g fora visibility ofmor etha n 1km .Ther ei sa strikin g resemblancebetwee n thisgrap han d thepictur eo fmea nwin d speeds (Fig.3.23) .

3.5Large-scal eweathe rpattern s Thegenera lmeteorologica lpictur eo fWes tAfric aan d theadjoinin g centraleaster npar to fth eAtlanti cOcea ni nsprin g ischaracterize db y a belt ofhig hpressur e over theAtlanti c Ocean (atmospheric pressure 1015-1040mbar )an da nare ao flo wpressur eove rcentra lnorther nAfric a (pressure under 1010mbar) .Furthe rnort ho fthi s rather stableare aw e find thebel tbringin g thealway schangin gmixtur eo fhig han dlo w pressurearea s toWes tEuropea ncountrie s (Fig.3.27) .Th epresenc eo f thehig hpressur eare aove r theAtlanti cOcean ,whic hi smostl yfoun d between 10 and 40 Nan d thelo wpressur eare aove rnorther nAfric alea d toa stabl ean dhighl ypredictabl ewin dpatter nknow na sth enortheas t tradewinds .O nth eMauritania n coast thesewind sblo wmor eo rles s continuously fromnorther ndirection s thewhol eyea rroun d (compare figure 3.24).Th ehig hpressur earea si nth e10-4 0 Nare aar eno t static,bu tmostl ymov e toth eeast ,expan d ordecreas e insiz ean dma y change inpressure .Thes emovement san dchange s largelyexplai nth e

40 differences inweathe r fromda y toda yalon g theMauritania ncoast . Twoexamples ,base d ondat afro mweathe rmap so fth eDeutsche r Wattendienst,Offenbach ,wil lb edescribed : On8 Apri l 1985a hig hpressur eare a (1035mbar )wa s found atth e AtlanticOcean ,halfwa ybetwee nth eAmerica ncoas tan d theCanar y Islands (35 N,5 0 W).B ytha t timeth eBan cd'Argui nwa ssituate d ina broa d zoneo frelativel y calmai rwit ha natmospheri c pressureo fabou t 1013 mbar.Durin g thefollowin gday sth ehig hpressur eare aslowl ymove d eastward,leadin g toa graduall yincreasin gwin dspee do nth eWes t Africancoas tan d increasingatmospheri c pressure.O n1 1an d 12Apri lth e centreo fth ehig hpressur eare awa ssituate dove r theAzore san deve n reached 1040mbar ,leadin gt onorth-northeas twind so f 15m/ so nth e Canary Islandsan d 25m/ so nth eCap eVerdia n Islands.O nth eBan c d'Arguin thisweathe r situationle d todus tan d sand storms.O n 13Apri l a lowpressur earea ,comin gfro mth eSahara ,graduall ysprea d outi n northeast direction,leadin g tocalme rweathe rcondition so nth eWes t Africancoast .O n 14Apri lth eAzore shig hpressur eare aonl ymeasure d 1030mbar ,stil lslowl ymovin geast .B y1 5Apri li tarrive d inNorthwes t Spain,pushin g theNort hAfrica nlo wpressur eare a towards theeas ttoo . From 17Apri lonward sanothe rhig hpressur eare aa tth ecentr e ofth e AtlanticOcea nstarte d going thesam edirectio nbu tappeare d tofollo wa more southerly routei nth efollowin g days.Becaus e ofit sdifferen t routean d lowermaxima lpressur e (about 1030mbar )th eeffect so nth e Bancd'Argui nwer ewel lnotabl e (ratherstron gwind sfro mth enorth )bu t nota sintens ea sdurin g thepassag eo fth ehig hpressur eare ath ewee k before.B y2 2Apri li tha dlos tsom e pressure (1020mbar )an dwa s situatedwes to fth eCanar y Islands,a da ylate ri tstarte d toexpan ddu e towhic hwin d speedsgraduall ydroppe d onth eWes tAfrica ncoast . Theextraordinar y dipi natmospheri c pressurefro m 21-28Februar y 1986 isexplaine d by therathe rnortherl ypassag eo fa hig hpressur earea .O n 21Februar ya largehig hpressur eare ao fove r 1020mba rwa ssituate d west ofth eCanar y Islands.Tw oday slate r itha d settled overMorocc o and southern Spain,leadin g torathe rlo wpressur ea tit ssouther nrang e andeasterl ywinds .A tth esam etim ea lo wpressur eare ao fles stha n 1010mba rove rCentra lAfric awa sspreadin g northward.B ythi stim eo n thewhol eCentra lAtlanti c 1010-1015mba rwa smeasured .O n2 5Februar y thelo wpressur ezon eha dmove d evenfurthe rnorth ,th ehig hpressur e zoneove rNort hAfric a losingmuc ho fit spowe ran dbreakin g upint o

41 several pieces.Th e situation started recovering tonorma lb y2 6Apri l whenanothe r highpressur eare astarte d forming onth ecentra lpar to f theAtlanti c Ocean,southwes t of theAzores ,expandin g itsrang eswiftl y inth efollowin g days.B yearl yMarc hth esituatio nwa smor eo rles sbac k tonorma lagain .Th espreadin g outo f thelo wpressur eare aove r Northwest Africa byth een do fFebruar y lead torelativel y lowmaximu m temperatures atth eBan cd'Argui nfro m 25Februar y until4 Marc h 1986an d toprevailin gwind sfro m thenothwes t during theafternoon ,bringin gi n relatively coolan dhumi d air fromth eAtlanti cOcean .

Figure 3.27. Weather situation on 28Marc h 1985a t the northern hemisphere,wit h emphasis on the location of high and low pressure areas and wind directions.Modifie d after: Europäischer Wetterbericht, Deutscher Wetterdienst, Offenbach (daily issues).

~~42 HYDROGRAPHICAL MEASUREMENTS~~

CorJ . Smit,Anne-Mari e Blomert,Andr éMeijboom ,Wi mJ .Wolf f & LeoZwart s 4.1 Introduction Though information onth emoment so fhig han d lowwate ran d predictions ontid elevel si spermanentl y availablefo rDakar ,Senega l (Admirality Tide Tables),onl y limited information ontida lparameter s forth eBan c d'Arguin wasavailable .I nth eliteratur eonl yth eshap eo fon etida l curve,base d uponmeasurement sdurin g 12hour swa savailabl e forIouik , next toa ma pshowin gcotida lline sfo rpar to fth eBan cd'Argui n

Figure 4.1. Ott tide registration device mounted on ahollo w pipe on the edge of the channel close to the Iouik camp.Th e small ladder was often used by roosting Reed Cormorants Phalacrocorax africanus.

~~43 W/f*TERLEVEL ,C M~~

~~300-~~

~~200~~

~~-IOO-~~

Flgure 4.2. Quarterly registration of the tide height in the channel next to the camp near Iouik.Th e y-axis for this graph was chosen arbitrary. Open symbols denote measurements from 12Marc h 1986 (around spring tide), dots refer to 18Marc h 1986 (around neap tide).

(Altenburg et al. 1982). During the 1985 and 1986 expeditions a continuous registration of tidal fluctuations wasmade .Thes e measurements were mainly taken to determine the duration of the flooding of the tidal flats,i n order to quantify duration of the feeding time available to the birds in the course of time.Becaus e itma y beo f benefit for future research at the Banc d'Arguin the results of the tidal registrations are presented here,nex t toa n analysis of the measured parameters.Thi s analysis allows for predictions on themoment s of high and low water as well as tide levels in the Baie d'Aouatif,base d upon known parameters for Dakar. Seawater temperatures have been measured both in 1985an d 1986,bu t the frequency in 1986wa s much higher. Only the 1986dat a have been analysed. During April 1986wate r temperature and salinity have been determined at a number of stations in the vicinity of Iouik. The aim of

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~~<*6 WteW T\DE (OUIK , MEAiUttED CM~~

~~J20~~

~~s300~~

~~290~~

~~2&>~~

~~2qo~~

~~220~~

~~200 y=*O.S + A.64X. r=O.BBH II: 132 P<0.01 4*> —I I 1 L ioo -MO HO 13o -Wo ISO 460 t?o TIDE EAKA», PREDICTED CM~~

~~Figure 4.5. Measured water levels athig h tide inIoui k (cm)i nrelatio n to thepredicte d water levels inDakar , Senegal (cm)fro m 12Februar y- 21Apri l1986 .~~

LOW TIDE louiK, MEAsaftEo o* fa*

«0

~~136~~

~~420~~

~~90 Yr ?t*.S 4 Q32 * r« o.?i€» 0=152 P~~

~~40 SO 6o 90 90 LOW -fioe DAKAR , PREDICTED, CM~~

~~Figure 4.6. Measured water levelsa tlo wtid ei nIoui k (cm)i nrelatio n toth epredicte d water levels inDakar ,Senega l (cm)fro m 12Februar y- 21Apri l1986 .~~

~~kl DOG OOG D TIME DIFFERENCE man -noe~~

~~LO*J TIOC~~

~~4-00 15/2 20/2 25/2 1/3 5/3 lO/3 «/3 0O# 25/3 3Q/3 5/4 14*4 «A* 20IH~~

Figure 4.7. Differences inhour s and minutes between the moments of high and low tide in 1986 in Iouik (measured)an d Dakar,Senega l (predicted) in the course of time. Symbols in the top part denote moon phases (compare figure4.3) .

~~thesesample swa st oobtai na genera lpictur eo fth edistributio npatter n ofwate rtemperatur ean dsalinity .~~

4.2Method s Registrationswer emad eusin ga mechanica lOt tX Xtid eregistratio n device,mounte d ona hollo wpip eo fabou t6 meter slengt han d 20c m diameter (Fig.4.1) .Th ewhol einstallatio nwa sborrowe dfro m Rijkswaterstaat,De nOeve r (Ministryo fPubli cWork san dTransport , Directory Noord-Holland),an dwa sverifie d and stamped priort oth e expeditions.Th einstallatio nwa s setu pi nth echanne lnex t toth ecam p ata site ,dee penoug ht oallo wfo rcontinuou smeasurements .Th e registration partconsist so fa cilinde r floating freelya t thewate r surface insideth ehollo wpipe ,whic h isconnecte d througha wir et oa

48 pen.Registration swer emad econtinuousl y onrotatin g sheetso fpaper , therunnin g speedo fwhic h issteere d bya clock .Th efina lresul to fth e measurementsconsist s ofa grap h showing continuous registrationso f waterlevel s inth ecours eo ftime . Seawater temperaturewa smeasure d withhydrographica l thermometers witha naccurac yo f0. 1 C.Thes ewer eequippe dwit ha smal lcontaine rt o storea certai namoun t ofse awate r toallo wfo rcorrec t temperature reading.Temperature sa tIoui kgenerall ywer etake n2- 4time sdaily , standingkneedee pi nth ewate ro f thechanne lclos e toth eIoui kcamp .O n someday stemperature swer etake nmor efrequentl y toanalys eth e influenceo f thetide san dai rtemperature . Observationsa tothe rstation s weremad e froma smal lboat . Temperaturemeasurement swer emad ewit ha nhydrographica l thermometer whichwa smove d through thewate ra tabou t0. 4m depth .Temperatur e readingswer emad eafte r 1min . Seawate r sampleswer ecollecte d inpolyethylene,bottle sthoroughl y rinsedwit hse awate rbefor ecollectin g thesamples .Th ebottle swer e closed very tightlyan d transported toth eNetherland swher eMr .R . Manuels (Netherlands Institutefo rSe aResearch )carrie d out thesalinit y determinations.T othi sen dth esample swer edilute dwit ha nequa l quantityo fdistille dwate r (accuracy+ 0.0 1 g)afte rwhic h salinitywa s determined bymeasuremen t ofconductivity .Th esalinit y thusdetermine d wasmultiplie d bya facto r2 .Al lmeasurement swer ecarrie d outa tleas t induplo .

4.3Result s 4.3.1 Tides Anexampl eo ftw o2 4hour sgraph so ftid elevel si sgive ni nfigur e4.2 . Thecurv e isa typica lexampl eo fsemi-diurna l ocean tidalcurve .Thi si s somewhat surprising,considerin g thefac t that the tidalcurrent ,comin g fromth esout hi sblocke d byth eislan do fTidr aan dha st og oabou ta longwa yt oreac hIoui kfro mth enorthwest .Apparentl y thetida lchannel s between Iouikan d theope nocea nar ewid eenoug h toallo w the tidalwate r masses toflo wi nan dou tunhampered .Ther ei sa nobviou sdifferenc ei n tideheigh t between spring tide (opensymbols )an dnea p tide (dots)a s wella sgenerall y there isa differenc e intid eheight sbetwee ntw o succeedinghig han d lowtides .Thi sdifference ,th edissimilarit y ofth e diurnal tide,als oappear s fromfigure s4. 3an d 4.4 showingth e

49 successive levels ofhig han d low tide in 1985an d 1986.Th eexplanatio n for thediurna l dissimilarity isth epositio no fsu nan dmoon .Bot h objects,an d theinteractin ggravitationa l forcesthe ybrin gabout ,ar e positioned quitedifferentl y ina 12hour sinterval ,bu tar erathe r comparable inpositio nwhe nconsiderin g a2 4hour speriod .Tw osuccessiv e highan d lowtid elevel s thereforema y showconsiderabl edifferences , muchmor ea swhe n twosucceedin gmornin go revenin g tidesar ecompared . Figure4. 4als oshow stha tth eleve lo fhig htide sgraduall ydecrease si n thecours eo f time.I nman yplace si nth eworl d thehighes t springtide s occur towards theequinoxes ,i.e .aroun d 21Marc han d 21Septembe r21 , whenda yan dnigh tar eequall y longan d sunan dmoo nar emos tnearl yi n line.Thi sphenomeno nma ywel lexplai nth edecreas ei nhig htid elevels , noted inIouik ,bu tmeasurement s overa longe rperio dwil lb eneede dt o demonstrate itmor eclearly . Figures 4.3 and4. 4als osho wtha t twosucceedin g spring tidesan d neap tideshav edifferen thig han dlo wtid elevels .Thi sdifferenc ei s broughtabou tb ydifference s ingravitationa lforces ,cause d byth e positiono fsu nan dmoo ni ntw oweek s intervals (alternately positioned onth esam esid eo fth eeart han do nopposit e sides).On ema yals onotic e thata sprin g tideleadin gt oa larg etida lamplitud e isfollowe d bya neaptid eshowin g thesame ,wherea s spring tideswit ha relativel y small amplitudear ebein g followed bynea ptide sshowin g thesam e characteristic. Theaverag e tidalamplitud ea tIoui kove r3 |sprin gan dnea ptid e periods (from 18Februar y- 1 0Apri l 1986,correspondin g to9 0hig htide s and 95lo wtides )amount s to 1.61m an d thereforecoincide swit hth e normal tidalamplitud e found onope nocea ncoasts .Durin g springtide s thetida lamplitud eapproximatel y is2.0 0m (1.85-2.15o naverage ,mea n over4 sprin gtid eperiods) ,durin gnea ptide st o1.0 0m (0.80-1.40m , meanove r 5nea p tideperiods) . Except fortw oregistration so f themomen t ofhig h tidea tth eislan d ofNai ri n198 5n otid eregistration selsewher ea tth eBan cd'Argui nwer e made.Dat afro mNai rindicat etha thig htid eca nb eexpecte d about 5-10 minutesprio r toIouik . Tidesi nIoui kwer ecompare d tothos e inDaka rb yusin gou rmeasure d dataan d thepredicte d datafro mth eAdmiralt yTid eTable sfo rDakar . Tideheigh ta tIoui kappear s tob ehighl ycorrelate d tothos epredicte d forDaka r (Fig.4. 5an d 4.6).Ther eis ,however ,quit ea larg evariatio n

50 inth emeasure d data,especiall y forlo wtides .Usin g figures 4.5an d 4.6 bothhig han d lowtides ,th elo wwate rleve la t Iouikca nb epredicte d witha naccurac y ofc .3 0c m (being the rangeo fdeviation s fromth e mean), thoughi nmos t caseswit ha highe raccuracy .Evidentl y wind isa factor influencing the tideheigh ta t Iouik.A nanalysi s ofth e difference between thepredictio n forDaka ran d themeasure d valuefo r Iouik,i nrelatio n towin d speedan dwin ddirectio n showstha twind sfro m westerndirection s generally yield somewhathighe rwate r levels inIoui k aspredicted .O nth eothe rhan dwind s fromeasterl ydirection sgenerall y lead tosomewha tlowe rwate rlevels .Ou ranalysi showeve rals odoe sno t fully explain thedifference sw eencountered . Themomen t ofhig h tidei nIoui ko naverag elag s4 hour san d5 5 minutesbehin dDaka r (meanove r 133hig htide sfro m 12Februar yan d2 1 April 1986).Fo rlo wtide sth etim ela gamount st o5 hour san d 3minute s (meanove r 133lo wtide si nth esam eperiod) .Figur e 4.7demonstrate s thataroun d fullan dne wmoo nth etim ela gi ssomewha t larger,bot hfo r highwate ran d forlo wwater .Fo rperiod saroun dhal fmoo nth etim ela g isrelativel y short.Fo rhig h tidesaroun d spring thetim ela gamount st o 5.07hour s (meanove r 40hig h tides),fo rhig htide saroun d neap tideth e timela gi s4.4 3hour s (n=51).Fo rlo wtide sth efigure sar e5.2 4hour s (n=45)an d 4.49hour s (n=48)respectively .

4.3.2 Seawater temperatures Water temperatures Inth echanne lclos et oth eIoui kcam psho wa gradua l increasei nth ecours eo fth eseason ,startin gfro mapproximatel y 19C b y midFebruar y toabou t 21°Cb ymi dApril .Figur e 4.8clearl y showsthi s increase.A t thesam etim ethi sgrap hdemonstrate s thatth eincreas ei n water temperature coincidest osom eexten twit h theai rtemperatur e increase.Becaus e of therelativel y slowheatin gu po fth ewater ,a sudden increase inai rtemperature s isno timmediatel y reflected inwate r temperatures.Th esam eapplie s fora nai rtemperatur edecreas ebu tth e courseo fai r temperatures iswel l reflected inwate r temperature changes. Apart fromchange s inseawate r temperature during thewhol e observation period therear enotabl edifference s inth ecours eo fth e day.Figur e 4.9 showsa nincreas e inwate r temperaturesa ssoo na s morning sunheat su pth ewate ro fth echannel .Th ehighes twate r temperaturesar emeasure d from 12a.m . onwards.Th ebes tcondition sfo r

~~51 TE.MPERATZJRE:, *C~~

~~21 ÄAlR 7 1~~

~~18 _ /o SEA ^» V~~

~~^6 l i i i i i i i i i i i i i i i \2/Z \S/2. 20/2 /5 2S/3 Jfc/5 5/M *>«« *»M ÖO*«~~

~~Figure 4.8. Mean sea water temperatures ( C) in the channel near the Iouik camp and daily mean air temperatures ( C) in the course of the 1986 observation period.~~

~~5BA RÄTTER TEMPERATURE,t~~

~~-16 iB SO M MOOR~~

~~Figure 4.9. Mean sea water temperatures (C ) per hour in the channel near the Iouik camp in February-April 1986.~~

~~52 3tA VwÄTER TEMPERATURE, C~~

~~LW MW LW HW LW 24 ' ' ' " '' '' " &/<* - a^M 'm£. o^^-^y "•— 2a •v~ ^ -*^- • ^ /> o-- iiy H^ ^ / 20 ^ «t t t t t \ -18 *J LW L HW HW LW HW~~

~~1 .1 1 1 1 ! 1 1 L i l i 1 1 1 II . , - S tó12-W<6tóiDÏ22^2 S 4o 42. AHtó Hoafi~~

~~Figure4.10 . Seawate r temperaturesi nth echanne lnea rth eIoui kcam p on8/ 9Apri l 1986(ope ncircles )an d 15/16Apri l 1986(dots )i nrelatio n tohig hwate r (hw)an dlo wwate r (lw).~~

takinga refreshin g butno tunpleasan tbat har ebetwee n 1an d 4p.m . Somewhat laterdurin g theda ydeclinin gai r temperatures turnbathin gt o beles sagréable .Durin g thenigh t seawatertemperature sma ydro p considerably thoughfigur e4.1 0demonstrate s thisi sno tnecessaril yth e case.Figur e 4.10 showssuccessiv e seawater temperatures intw oday si n relation tohig han dlo wtide .O n 15Apri lth etemperatur e inth echanne l at 8a.m .amounte d to2 0C (lowe rgraph) .A sa resul to fa nincreasin g airtemperatur e inth ecours eo f theday ,th ewate r temperature inth e channeldecrease d aswell ,unti labou t 1hou rafte r lowwater .B ythe n somewhatcolde rwate rfro mth elarg etida linle twes to fIoui kcam ein , causinga temporar ydro pi nwate r temperatures.Maximu mai rtemperature s onthi sda ywer emeasure d between 12a.m .an d 3p.m .an damounte d to 26.4C .Thes e temperatures resulted ina renewe dwarmin g upo fth e channelwater .Du e toth efac t thatai rtemperature sdurin g thenigh t only slightlydroppe d to2 1C ,th ewate rtemperatur edi dno tdecreas ea s well.O nth econtrary ,th eincomin ghig h tideeve nallowe d fora sligh t increasea t 2a.m . inth emornin g of 16April .Minimu mai r temperaturei n theearl ymornin gwa s 18.3C .Thes erelativel y lowai rtemperature si n theearl ymornin g at thesam e timeresulte d ina gradua l coolingof fo f thechanne lwate ro n 16April ,fro m 8a.m . onwards thecours e ofth e

53 seawater temperatures isver ymuc h thesam ea so nth eda ybefore .8 April,wa sa warme rda ya scompare d to 15April .Maximu m temperatures weremeasure d around 12a.m .an damounte d to29.6°C .Thes e relatively highmaximu m temperatures resulted inhighe rwate rtemperature sa s compared to 15April .Th e9 hour sdifferenc e inhig han dlo wwate r resulted ina mor egradua lcours e ofwate rtemperatures .

~~Table 4.1. Observations of temperature and salinity near Iouik in April 1986.~~

~~Nr. Place Date Time HW/LW Iouik Temp Sal.~~

1. Near Biological Station 11Apri l 7.15 h LW 9. 15 - 40.82 2. Opposite Iouik 11 (1 7.30 h " - 40.54 3. N of Tidra 11 fl 7.40 h - 39.41 4. NW of Tidra,N E of Arel 11 tl 8.00 h 1 - 38.21 5. Main channel N of Arel 11 M 8.30 h 1 - 38.27 6. S of Arel 11 M 9.00 h 1 - 38.23 7. Baie d'Aouatlf, near Biol. Station 12 April 15.55 HW 16.0 0 21°.4 40.33 8. " ,N W corner 12 II 16.00 1 21°.4 40.43 9. " ,N part 12 II 16.05 1 21°.5 40.60 10. " ,N E corner 12 11 16.10 21°.4 41.10 11. " ,N E corner, end of 12 11 16.15 21°.4 41.22 channel 12. " ,E part over flats 12 II 16.20 1 22°.0 41.36 13. " ,nea r Biol. Station 16 April 12.15 LW 12 00 21°.4 40.76 14. " ,N W corner 16 M 12.23 1 21°,2 40.94 15 " ,N part 16 H 12.28 1 21°.2 41.01 16. Baie d'Aouatif, NE corner 16 H 12.32 LW 12.0 0 21°.2 41.63 17. " ,N E corner, end of 16 H 12.37 I 21°.4 41.88 channel 18. Baie d'Aouatif, near Biol. Station 16 M 13.40 1 21°.2 40.73 19. Opposite Iouik 16 H 13.45 1 20°.9 40.23 20. N of Iouik, entrance of channel 16 ii 14.00 ' 22°.0 39.89 21 N of Kiaone-West 16 n 15.07 " 22°.2 39.73 22 Halfway Kiaone and Iouik 16 ii 15.30 It 22°.2 39.92 23 . NNE of Arel 7 April LW at Arel 37.84 24 . S part of Bay NE of Serini 20 April HW at Serini - 54.50

5h 4.3.3 Salinity Table 4.1 summarizesal lobservations .Figur e 4.11 presentsa genera l pictureo f thedistributio n ofsalinit y inth evicinit yo f Iouiki nApri l 1986.Figur e 4.12give s theresult so f twoserie s ofobservation s inth e mainchanne lo fth eBai ed'Aouatif . Earlier observations ontemperatur ean d salinity ofth eBan cd'Argui n havebee npublishe d byReyssa c (1977)an d Sevrin-Reyssac (1982, 1984). Thesema yb esummarize d asfollows .I nth eoffshor e areas salinitiesar e about 35-36/o oS .I nth eare aaroun dAre lvalue so fabou t 38/o ooccur , whereasclos et oth eshor e (e.q.nea rIoui kan dTeichot )value sove r 40/ ooccur .I nhydrographicall y isolatedwaters ,suc ha sth eBai ed eSt .

~~Figure 4.11. Salinity (o/oo)i n tidal channels.~~

~~55 %oS~~

~~4t.A /ïfc APRIAPRILL LWS TEMP 22.2~~

~~416 12 APRIL HW TEMP 22.0 41* 12 APRIL M WS 21.8 41.1 2i.6~~

~~41.0~~

~~16APRI L Lw TEMP 2\M 40.8~~

~~4aé~~

~~4Q4~~

~~40.2~~

~~lOCIlK BS A~~

~~Figure 4.12. Salinity (o/oo)an d temperature of the sea water in the Baie d'Aouatif.~~

Jean,ver yhig hvalue s (upt o81.6°/o oS )hav ebee nregistered . Ourobservation s fitperfectl y inthi spattern .Nea rAre lw eobserve d salinitieso fabou t38°/oo ,nea rIoui k40-41°/o oan di nth eisolate dba y northeasto fSerin iw efoun d 54.5°/oo.Hence ,a gradien to fsalinit y occurs from thecoas t toope nsea .Thi si sconfirme d byth edat ai n figure4.l2 .I nth emai nchanne lo fth eBai ed'Aouati f anincreas eo f salinitywa sobserve d fromth eseawar d enda tIoui kt oth elandwar dend , withhighe r salinityvalue sa t lowtide .A spointe d outbefor e thisi s due toth estron gevaporatio na tth eBan cd'Arguin . Temperaturemeasurement s showa mor eregula rpattern .Tabl e4. 1an d figure 4.3 showtha tth emaximu mdifferenc ewa sonl y 1.3C .Temperature s recorded bySevrin-Reyssa c (1984)i nMarc har eslightl yhigher . WADER AND WATERBIRD COUNTS 198 5

~~TheunisPiersma ,Abo uGuey e& Cheikhn aMbar é~~

During theexpeditio n severalcount so fth ewader san dwaterbird so f certainarea swer emade .Bot ho nth ePresqu'il ed eCa pBlan cnea r Nouadhibouan d inth eBai ed'Aouati fan d surroundingsnea rIouik ,count s wereperformed .Figur e 5.1 showsth ecountin g trajectsi nth eBai e d'Aouatif and figure 5.2 thedelineatio no fth ecountin g trajectso n Presqu'ild eCa pBlanc .I tshoul d beclea rtha to nPresqu'il ed eCa p Blancno tal larea swher ewader scoul dpossibl yoccur ,wer ecovered .Th e northernpar to fth eBai ed el'Etoile ,an dth ebeache snea rL aGuer ao n thewes t sideo fth epeninsula ,fo rexample ,wer eno tvisite ddurin gth e counts.Th eresult so fth ewade rcount sar epresente d intable s5. 1t o 5.8an d theresult so fth ewaterbir d countsi ntable s5. 9 to5.16 . Table5. 1 summerizesth eresult so fth ethre ecount si nth eBai e d'Aouatif and compares thesewit h theresult so fa nearlie rcoun to fth e samearea ,i nJanuar y 1980(Altenbur g eta l 1982). Itwa sencouragin gt o discover that thetota lnumbe ro f 141,000wader san dals o thebreakdow n indifferen t speciesi scomparabl ebetwee n theJanuar y 1980an d theMarc h 1985count .Encouraging ,becaus ethi ssuggest sbot hsom econstanc yi n waderpopulations ,consistenc y between thecount san donl ylimite d departure ofwader s toth enort hbefor ew e (finally!!)arrive d onth e study site.I nsprin g 1985,th etota lnumber so fwader ssteadil y declined.On eo fth ecountin g trajects (VI,th eNorthwes t Bayo rEbel k Aiznai inHassania )wa scounte dmor e frequently during thestud yperio d (Table 5.2;se eals oTabl e 5.17 fordat afro m 1986),bu twade rnumber s showed thesam egenera l trendsthere . Thecount s onth ePresqu'il ed eCa pBlan cwer emad e justbefor ean d justafte r theperio d ofsta ya tIouik ,an d thereforeyiel d datao n

57 numbers ofwader s froma longe r timespa n (range ofdates )tha nfo rth e Baied'Aouatif .Tabl e 5.6 shows thatnumber so fwader scounte d duringlo w tideo rdurin ghig h tidewer eno tver ydifferen t (notconsistentl y different between thespecie s anyway).A compariso nbetwee n tables 5.6 and 5.7 shows thatbetwee n 15Marc han d 3May ,tota lnumber sha ddecline d by 1500/4000x 100%= 38% .Thi scompare swit ha 42 %declin ei nth eBai e d'Aouatif (Table5.1) . The resultso fth ewaterbir d counts inJanuar y 1980an dMarc h 1985 alsosho wrathe rgoo d resemblance.Onl y thenumbe ro fSpoonbill sappeare d tohav eincrease ddramaticall y (duet oth esettlemen t inth ebreedin g colonyo nth eIsl eo fZir ai nearl yMarch) ,an d thenumbe r ofLesse r Black-backed Gullsha ddecrease d (departure onnorthwar dmigration?) . Tables 5.14t o5.1 6nicel y illustrate thatth enumbe r of(mainl y juvenile)Greate rFlamingo' saroun dNouadhibo uremaine d ratherconstan t throughMarch-May .

~~o 1 1 JW»1~~

~~Figure 5.1. Map of the Baie d'Aouatif, the Presqu'île d'louikan d surroundings. The star indicates the camp site.Countin g trajects are indicated by Roman numerals.~~

58 Table 5.1. Results of the high tide counts of waders In the Bale d'Aouatlf and surroundings in spring 1985.Fo r comparison, the results of the high tide count of the same area byAltenbur g etal . (1982)i n January 1980ar e also listed.

~~19 January 24Marc h 17Apri l 25Apri l Departed 1980 1985 1985 1985 24March - 25Apri l in Z~~

Oystercatcher 4987 1065 275 393 - 63Z Avocet 0 0 4 0 Ringed Plover 11053 4522 3555 2928 - 35Z Kentish Plover 870 1383 850 456 - 67Z Grey Plover 2231 1253 1921 1702 + 36Z Knot 40560 45513 40754 19028 - 58% Sanderling 978 479 520 938 + 96Z Little Stint 703 3122 5052 4345 + 46Z Curlew Sandpiper 8385 4412 13633 5164 + 17Z Dunlin 43427 56085 22163 31845 - 43Z Bar-tailed Godwit 32107 18518 14578 13312 - 28Z Whimbrel 612 245 476 244 oz Curlew 358 320 52 0 -100Z Redshank 3552 2978 965 699 - 77Z Greenshank 486 54 148 237 +339Z Common Sandpiper 0 0 0 17 Turnstone 1539 640 1°'6 758 + 18Z

~~Total 151848 140589 105912 81983 - 42Z~~

Table 5.2. Results of the high tide counts of waders in Ebelk Aiznai (the Northwest Bay,are a VI)i n spring 1985.O n 14Apri l only the Bar-tailed Godwits were counted here: 2304Individuals .+ » present,bu t not counted. The count of 7Ma ywa s kindly made available by Pierre Campredon.

~~24 3 16 22 24 27 7 March April April April April April May~~

Oystercatcher 49 116 34 130 45 75 109 Ringed Plover 540 264 344 221 180 400 330 Kentish Plover 15 90 13 + 60 5 102 Grey Plover 325 127 400 646 385 232 321 Knot 10830 8383 9080 6326 6200 3500 3191 Sanderling 30 50 104 495 55 322 160 Little Stint 100 60 375 700 350 315 140 Curlew Sandpiper 300 195 3210 608 700 695 1082 Dunlin 3700 3220 2375 2560 2200 2422 1437 Bar-tailed Godwit 1282 2275 2507 1410 1525 822 760 Whimbrel + + 271 210 34 190 129 Curlew 70 3 1 3 0 0 0 Redshank 51 200 191 14 + 68 55 Greenshank 0 10 1 0 0 60 181 Common Sandpiper 0 0 0 0 0 0 3 Turnstone 21 24 193 201 ? 158 63

~~59 Table 5.3. Results of the high tide wader count on 24Marc h 1985 in the Baie d'Aouatif and surroundings. See figure 5.1 for delineation of the 7 counting trajects.~~

~~Traject 1 II III IV V VI VII Total~~

Oystercatcher 126 327 28 397 9 49 80 1065 Ringed Plover 603 715 363 1111 390 540 800 4522 Kentish Plover 160 70 218 770 25 15 125 1383 Grey Plover 233 450 86 20 9 325 130 1253 Knot 9716 21352 365 2760 0 10830 500 45513 Sanderling 28 7 39 140 165 30 70 479 Little Stint 30 655 260 1720 7 100 350 3122 Curlev Sandpiper 100 1300 848 1540 4 300 320 4412 Dunlin 14305 16825 7155 7080 3685 3700 3335 56085 Bar-tailed Godwit 738 10978 601 3509 10 1282 1400 18518 Whimbrel 17 28 73 60 7 + 60 245 Curlew 10 20 17 43 0 70 160 320 Redshank 872 1800 0 165 0 51 90 2978 Greenshank 0 20 0 14 0 0 20 54 Turnstone 23 72 17 35 432 21 40 640

~~Total 140598~~

Table 5.4. Results of the high tide wader count on 17Apri l 1985i n the Baie d'Aouatif and surroundings. See figure 5.1 for delineation of the 7 counting trajects. In traject IV three Avocets were seen,an d in traject VI one.

~~Traject I II III IV V VI VII Total~~

Oystercatcher 33 39 9 51 34 34 75 275 Ringed Plover 287 972 870 1080 2 344 0 3555 Kentish Plover 56 31 420 314 16 13 0 850 Grey Plover 584 241 398 232 0 400 66 1921 Knot 4442 11400 5800 2330 2 9680 7700 40754 Sanderling 57 33 90 131 105 104 0 520 Little Stint 1125 190 1660 1702 0 375 0 5052 Curlew Sandpiper 3541 5100 730 700 2 3210 350 13633 Dunlin 2258 1560 4700 7365 5 2375 3900 22163 Bar tailed Godwit 3581 1503 1508 1670 9 2507 3800 14578 Whimbrel 105 0 51 37 12 271 0 476 Curlew 0 0 0 11 0 1 40 52 Redshank 103 621 0 50 0 191 0 965 Greenshank 20 116 1 10 0 1 0 148 Turnstone 89 211 0 44 475 193 4 1016

~~Total 105908~~

~~60 Table 5.5. Results of thehig hwade r counts on 25Apri l 1985 In the Bale d'Aouatif and surroundings. See figure 5.1 for delineation of the 7 counting trajects.~~

~~Traject I II III IV V VI VII total~~

Oystercatcher 58 27 28 95 9 45 131 393 Ringed Plover 173 340 1410 546 99 180 180 2928 Kentish Plover 30 38 150 160 18 60 0 456 Grey Plover 174 173 626 285 9 385 50 1702 Knot 2800 250 6938 2290 0 6200 550 19028 Sanderling 46 10 510 192 45 55 80 938 Little Stint 850 580 850 1620 55 350 40 4345 Curlew Sandpiper 560 604 660 1980 10 700 650 5164 Dunlin 7400 4510 7700 8215 280 2200 1540 31845 Bar-tailed Godwit 1600 370 3480 4052 5 1525 2280 13312 Whimbrel 66 41 69 21 8 34 5 244 Curlew 0 0 0 0 0 0 0 0 Redshank 30 5 275 8 0 378 3 599 Greenshank 30 0 150 27 0 0 30 237 Common Sandpiper 0 1 16 0 0 0 0 17 Turnstone 22 33 190 43 263 140 67 750

~~Total 81983~~

~~Table 5.6. Results of thewade r counts of part of the Presqu'île de Cap Blanc (see figure 5.2) on 15Marc h 1985.~~

~~la Ha lib Ilia Illb Total Total Hour 11-13 13-17 16-18 10-13 17-19 Tide low after before low high a b low high~~

Stone Curlew 0 0 0 20 35 20 35 Oystercatcher 32 16 27 35 54 94 81 Little Ringed Plover 0 0 0 2 5 2 5 Ringed Plover 76 6 51 279 320 351 371 Kentish Plover 52 5 103 8 10 65 113 Grey Plover 66 89 67 25 10 180 77 Knot 180 30 180 82 15 292 195 Sanderling 72 1357 1869 74 195 1503 2059 Little Stint 0 0 25 0 0 0 25 Curlew Sandpiper 0 0 2 0 0 0 2 Dunlin 597 0 50 64 28 661 78 Ruff 0 0 0 0 1 0 1 Black-tailed Godwit 0 0 0 1 1 1 1 Bar-tailed Godwit 341 35 124 99 110 475 234 Whimbrel 48 1 1 12 10 61 11 Curlew 14 1 2 2 12 17 14 Redshank 59 0 1 1 1 61 2 Greenshank 0 0 1 12 21 12 22 Wood Sandpiper 0 0 2 0 0 0 2 Common Sandpiper 4 0 1 6 6 10 7 Turnstone 88 21 19 112 104 221 123

~~Total 4026 3467~~

~~61 Table 5.7. Results of the wader count of part of the Presqu'île de Cap Blanc (see figure 5.2) on 3Ma y 1985 (15Marc h 1985 Is given for comparison).~~

~~1 II III Totals 15Marc h 3 May~~

Oystercatcher 2 13 18 94 33 Little Ringed Plover 0 0 10 5 10 Ringed Plover 16 11 83 371 110 Kentish Plover 5 103 20 113 128 Grey Plover 49 32 33 180 114 Knot 90 22 139 292 251 Sanderling 241 385 631 1503 1257 Little Stint 1 25 6 25 32 Curlew Sandpiper 1 0 0 2 1 Dunlin 56 45 27 661 128 Bar-tailed Godwit 153 34 35 475 222 Whlmbrel 41 3 9 61 53 Curlew 3 0 3 17 6 Redshank 33 0 0 61 33 Common Sandpiper 4 2 2 10 8 Turnstone 96 86 108 221 290

~~Total 4091 2676~~

~~Table 5.8. Results of a wader count of the old harbour of Nouadhlbou (Area III,Fig . 5.2) on 10Ma y 1985.~~

~~Species Number~~

Stone Curlew 2 Oystercatcher 11 Little Ringed Plover 2 Ringed PLover 75 Kentish Plover 17 Grey Plover 8 Knot 142 Sanderling 215 Little Stint 5 Curlew Sandpiper 0 Dunlin 12 Bar-tailed Godwit 83 Whimbrel 8 Curlew 1 Turnstone 50

~~Total 631~~

62 Table 5.9. Results of thehig h tide counts of waterblrds in the Bale d'Aouatlf and surroundings Insprin g 1985.Fo r comparison, the results of the count of the same area in January 1980 (Altenburg et al. 1982)ar e also listed.

~~19 24 16/17 24/25 January March April April 1980 1985 1985 1985~~

Cormorant 253 308 158 287 Long-tailed Cormorant 875 920 483 471 White Pelican 20 0 6 13 W. Reef Heron (blue) 101 53 75 217 Little Egret (white) 45 11 0 Grey Heron 186 172 104 83 Spoonbill 191 1043 843 - Greater Flamingo 360 480 424 491 Black-headed Gull 12 6 0 1 Grey-headed Gull 45 22 82 26 Slender-billed Gull 218 713 2435 1666 Lesser Black-backed Gull 814 25 8 4 Gull-billed Tern 8 0 107 191 Caspian Tern 391 10 5 234 Royal Tern 114 360 734 258 Sandwich Tern 4 0 8 1 Common Tern 0 30 162 129 Bridled Tern 0 0 0 2 Little Tern 14 0 43 62 Black Tern 0 0 2 0

~~Table 5.10. Results of the count of waterblrds in the Baie d'Aouatlf and surroundings on 24Marc h 1985.Se e figure 5.1 for delineation of the7 counting trajects. On traject IIn o birds were noticed.~~

~~Traject I III IV V VI VII total~~

Cormorant 0 0 18 0 90 200 308 Long-tailed Cormorant 0 0 0 0 320 600 920 V. Reef Heron (blue) 2 0 0 1 15 35 53 Little Lgret (white) 1 0 0 0 7 3 11 Grey Heron 40 0 26 0 60 46 172 Spoonbill 95 0 48 0 200 700 1043 Greater Flamingo 260 122 13 0 65 20 480 Black-headed Gull 0 0 0 6 0 0 6 Grey-headed Gull 1 0 0 4 2 15 27 Slender-billed Gull 17 0 7 139 0 550 713 Lesser Black-backed Gull 0 0 25 0 0 0 25 Caspian Tern 0 0 0 0 10 0 10 Royal Tern 0 0 0 0 70 290 360 Common Tern 0 0 0 0 30 0 30

~~63 Table 5.11. Results of the count of water birds In the Bale d'Aouatlf and surroundings on 16/17Apri l 1985.Se e figure 5.1 for delineation of the 7countin g trajects.~~

~~Traject I II III IV V VI VII total~~

Cormorant 0 0 12 3 0 16 127 158 Long-tailed Cormorant 0 0 15 45 8 138 277 483 White Pelican 0 0 0 0 0 0 6 6 W. Reef Heron (blue) 0 0 2 5 11 4 53 75 Grey Heron 4 16 5 15 0 23 41 104 Spoonbill 3 0 0 12 0 28 800 843 Greater Flamingo 75 67 76 109 0 51 46 424 Grey-headed Gull 0 0 0 0 2 0 80 82 Slender-billed Gull 0 0 0 5 78 27 2325 2435 L. Black-backed Gull 3 0 0 5 0 0 0 8 Gull-billed Tern 35 31 13 8 0 0 20 107 Caspian Tern 0 3 2 0 0 0 0 5 Royal Tern 4 1 0 0 15 204 510 734 Sandwich Tern 0 0 0 2 0 6 0 8 Common Tern 0 0 0 2 30 130 0 162 Little Tern 2 0 0 0 2 39 0 43 Black Tern 0 0 0 0 0 2 0 2

~~Table 5.12. Results of the cour- of waterbirds in the Baie d'Aouatlf and surroundings on 24/25 April 1985.Se e figure 5.1 for delineation of the 7 counting trajects.~~

~~Traject I II III IV V VI VII total~~

Cormorant 4 3 6 3 1 20 250 287 Long-tailed Cormorant 4 0 0 20 0 60 387 471 White Pelican 1 0 0 0 0 0 12 13 W. Reef Heron (blue) 0 0 0 0 1 0 216 217 Grey Heron 0 7 0 16 1 5 54 83 Spoonbill 0 11 0 9 0 17 + > 37 Greater Flamingo 64 0 194 72 0 70 91 491 Black-headed Gull 0 0 0 0 1 0 0 1 Grey-headed Gull 0 0 0 0 8 1 17 26 Slender-billed Gull 1 2 12 150 10 31 1460 1666 L. Black-backed Gull 0 0 0 0 0 0 4 4 Gull-billed Tern 48 23 21 8 2 4 85 191 Caspian Tern 1 0 7 0 5 1 220 234 Royal Tern 0 0 0 0 10 28 220 258 Sandwich Tern 0 0 0 0 1 0 0 1 Common Tern 3 0 0 0 6 120 0 129 Bridled Tern 0 0 0 0 0 0 2 2 Little Tern 0 0 0 0 10 52 0 62

~~bk ' Table 5.13. Results of the high tide counts of waterbirds inEbel k Aiznai (the Northwest Bay, area IV) in spring 1985.~~

~~24 16 22 24 27 7 March April April April April May~~

Cormorant 90 16 95 20 40 72 Long-tailed Cormorant 320 138 260 60 30 198 W. Reef Heron (blue) 15 4 4 0 0 2 Little Egret (white) 7 0 0 0 0 0 Grey Heron 60 23 4 5 14 4 Spoonbill 200 28 8 17 34 25 Greater Flamingo 65 51 60 70 73 167 Grey-headed Gull 2 0 1 C 0 0 Slender-billed Gull 0 21 31 1 0 20 L. Black-backed Gull 0 0 0 i 1 0 Gull-billed Tern 0 0 4 + 21 Caspian Tern 10 0 1 0 6 Royal Tern 70 204 28 > 40 32 Sandwich Tern 0 6 0 3 17 Common Tern 30 130 120 » 6 70 Little Tern 0 39 52 } 49 51 Black Tern 0 2 0 ' 0 31

~~Table 5.14. Results of the counts of of waterbirds of part of the Presqu'île de Cap Blanc (see figure 5.2)o n 15Marc h 1985.~~

~~la IIa lib Ilia Illb Total Total Hour 11-1 3 13-17 16-18 10-13 17-19 Tide low after before low high a b low high~~

Cormorant 0 23 11 7 6 30 17 Cattle Egret 0 0 0 6 0 6 0 V. Reef Heron (blue) 0 0 0 1 1 1 1 Little Egret (white) 10 1 1 2 1 13 2 Grey Heron 10 9 6 33 36 52 42 Spoonbill 16 1 0 12 12 29 12 White Stork 0 6 6 0 0 6 6 Greater Flamingo 12 0 0 31 31 43 31 Black-headed Gull 0 0 0 42 120 42 120 Slender billed Gull 0 0 61 20 254 20 315 L.Black-backed Gull 0 362 270 178 420 540 690 Caspian Tern 2 63 52 74 39 139 91 Royal Tern 0 16 1 8 0 24 1 Sandwich Tern 0 8 91 12 10 20 101 Common Tern 0 2 0 8 0 10 0

~~65 Table 5.15. Results of the counts of waterbirds of part of the Presqu'île de Cap Blanc (see figure 5.2) on 3Ha y 1985.~~

~~I 11 III Total~~

Cormorant 0 3 0 3 Cattle Egret 0 0 1 1 W. Reef Heron (blue) 1 0 0 1 Little Egret (white) 5 1 4 10 Grey Heron 3 0 25 28 Spoonbill 0 9 7 16 Greater Flamingo 29 6 31 66 Slender-billed Gull 0 0 60 60 L. Black-backed Gull 14 321 350 685 Caspian Tern 3 16 45 64 Royal Tern 0 28 0 28 Sandwich Tern 0 80 68 148 Common Tern 0 395 30 425 Black Tern 0 37 7 44 White-winged Tern 0 0 3 3 Little Tern 7 39 2 48

~~Table 5.16. Results of a count ofwaterbird s of theharbou r of Nouadhibou (Area III,Fig . 5.2) on 10Ma y 1985.~~

~~Species Number~~

W. Reef Heron (blue) 2 Little Egret (white) 3 Grey Heron 12 Spoonbill 8 Greater Flamingo 26 Black-headed Gull 15 Slender-billed Gull 13 Lesser Black-backed Gull 130 Audouin's Gull 29 Gull-billed Tern 1 Caspian Tern 118 Royal Tern 23 Sandwich Tern 16 Common Tern 53 Little Tern 7 Black Tern 15

~~66 GNP «4ANC o~~

~~Figure 5.2. Map of Presqu'île de Cap Blanc indicating the counting transects I, II, and III.~~

~~Table 5.17. Results of some Incidental high tide counts in the Northwest Bay In February 1986.~~

~~Species 8 February 13 February 22Februar y~~

Oystercatcher 220 210 287 Ringed Plover 485 700 649 Kentish Plover 7 21 30 Grey Plover 269 642 115 Knot 5600 2750 3500 Sanderling 289 295 189 Little Stint 1 300 164 Curlew Sandpiper 520 440 500 Dunlin 4025 1950 4600 Bar-tailed Godwit 4100 2190 ? Whimbrel 400 8 511 Curlew 42 80 73 Redshank 490 67 41 Greenshank 7 13 1 Turnstone 148 (12 Feb. ) 69 57

~~67 ^ JLj/r} w*-^v *• t> \ V~~

~~e. VISIBLE MIGRATION 1385~~

Nelly E. van Brederode 6.1Metho d Duringou rstud ya t Iouikw emad eman yobservation so nvisibl emigration , mosto fthe mi nth eBai ed'Aouatif . Itwa si nthi sare a thatw ewer emos t activewit hmis tnetting ,cannon-nettin gan d feeding observations.Apar t fromth eobservation s during theseactivitie ssystemati cdat awer e collected at thenort h sideo fthi sbay .Durin g theseobservation stime , locality,species ,numbe ro fbird si neac hflock ,heigh tan ddirectio n wererecorded .O na fe woccasions ,lik ewhe nwatchin g froma hide ,i twa s possible tomak enote so nth eplumag ean d sexo fth ebirds .

6.2Result s Inthi schapte r theresult s ofou rmigratio n observationsa t theIoui k peninsulaan d thesurroundin gmudflat so fth eNorthwes t Bayan d theBai e d'Aouatif aregiven .Th eresult s ofth eoccasiona lobservation sa tothe r aregive nseparatel y intabl e6.1 . Observationso nmigratio nar eusuall yassociate d withquie tweathe r anda hig htid eonl yshortl ybefor edark .W ewil lse eho wmuc hthi si s truefo rth eBan cd'Argui n(Fig .6.1) . Whenw earrive da t Iouiko n2 1Marc hth eweathe rwa srathe rquiet . From 27t o2 9Marc h thewin d increased forth efirs t timedurin gou rsta y climbing toa mea no f8- 9m/sec .W eha dou rfirs texperienc ewit hmil d sandstorms.Afte r these threeday swit hhardl yan ysign so fmigratio nth e wind suddenlydroppe d to7 m/se can d lesso n3 0Marc han d thenex teigh t days.Fro m8 Apri lonward sth ewin dincrease dagain .Notwithstandin gth e increasingwind ,on efloc ko f8 0Gre yPlover slef t thatevening .Fo rth e following fiveday sth emea nforc ewa s9-1 3m/se can dvisibilit ywa s greatlyimpaire d bysandstorms ,especiall y on 11April .O n 14Apri lwhe n

68 thewin dha d dropped below8 m/se can d visibility wasgood ,stron g migrationwa sobserve d again.Als oo nth efollowin g threeou to ffou r dayswit hwindforc ebelo w8 m/se cmigratio nwa s seen.Fro m 19Apri l onwards thewin d speedwa s 10-12m/se c forseve ndays .Durin g thisperio d however onlya sligh tdro po fth ewind ,especiall y inth eafternoo ngav e riset omigratio nactivities .O n2 1an d 22Apri lth ewin ddroppe d to8- 9 m/sec forthree ,respectivel y fivehours .O n2 5Apri l thewin d dropped to 10m/se c from 6.00h t o 19.00h .Thi ssligh t improvement gaveris et o massivedeparture .

~~KJZJMBEg OF BlCPS \«/)HPSPBED, M/S «tea~~

~~8O0~~

~~?oo~~

~~6oo 12~~

~~• _ K 500 io~~

~~400 8~~

~~300~~

~~20O~~

~~-loo~~

~~JOL 11 II 20J3 25/3 JO/3 àjc\ °>M W/u J&/U m/H22>M~~

~~Figure 6.1. Number of birds leaving in northerly direction from Baie d'Aouatif and Northwest Bay (columns)an d strength of the wind (m/sec)o n these days (dots).~~

Theimpressio ni stha tno t somuc h thewindforc eb yitsel fkep tbird s frommigrating .Usuall ya fe wday swit hincreasin gwindspee dan d especially impaired visibilityb ysandstorm s likeo n 10,11 ,1 2an d2 4 April,followe d bybette rweathe rcondition s incompariso nwoul dgiv e rise tostron gmigration ,especiall y thefirs tda yafte r theweathe r

69 improvement.Th emea nwindforc eo nth efirs tda yo fthes emigratin g periodswa s7 m/se c on3 0March ,8 m/se c on 14Apri lan d 11m/se c on2 5 April. Migrationmostl y occurred between 17.00h an d 19.30h (Fig.6.2) . Birdslef tbetwee n 15.00h an d 16.00h onl yo n25 ,2 6an d 27April ,whe n strongmigratio n occurred aftera perio dwit hstron gwind san dimpaire d visibility.Afte r 20.00h bird swer eonl yhear do n3 0Marc han d 31March . Thisi si ncontras twit h thesituatio n insprin ga t SidiMoussa ,Morocco , wheremigratio nwa sobserve d severaltime salmos tever ynigh t (Van Brederodee tal . 1982).Th estud ya tSid iMouss a tookplac erigh talon g themigratio ncorridor .A t theBan cd'Aouati f however,ou rcam pwa sabou t 2k msouthwes tfro mth enorther nsid eo fthi sbay ,th eplac efro mwher e thebird s tended toleave .Also ,th enight sa tSid iMouss awer ever y quiet.A t theBan cd'Argui nhoweve rver yfe wnight swer esuitabl efo r hearing birdsa tall .Th efac t thatn obird swer esee nleavin gbefor e 15.00h i sprobabl yno tcause db y thelocalit yo fth ecamp .Ou r activitiesdurin g theda ywer esprea dacros sth eentir epeninsul aan dit s surroundingmudflats .Betwee n 17.00h an d 19.00h th enumbe ro fbird s

~~1? 18 19 2o TIMEO P T>Ay~~

Figure 6.2. Number of flocks of migrating waders (dots)an d numbers of waders (open circles)leavin g the Bale d'Aouatif and the Northwest Baya t a given time a day (15 stands for 15.00-15.29 h, etc.) from 24Marc h till 29April . 70 leaving isrelate dwel l toth enumbe ro fflocks .Thi s isi ncontras twit h thesituatio nbetwee n 15.00h an d 17.00h whe nbird slef t inlarg e numbers inonl ya fe wflock so ronl ya fe wlef t insevera lflock s (Fig. 6.2).

~~VUMBEßO TBRO S~~

~~SOO-~~

~~ßQÖ 2B/3JQ 0 4/4 »*y V4/<4 ib/U 2U/4 23A~~

~~Figure 6.3. Numbers of Oystercatchers leaving in northerly direction from the Baie d'Aouatif and the Northwest Bay.~~

~~MUH6Eg OF B»er>5~~

~~30O~~

~~TOO~~

~~-too~~

~~iO/3 25/3 JO/3 4A» S/<4 m/{\ try^ 2MM 2S/4~~

~~Figure 6.4. Numbers of Redshank leaving in northerly direction from the Baie d'Aouatif and the Northwest Bay.~~

~~71 NUMBE« OF" "fei«D S~~

~~2O0~~

~~Aoo~~

~~1 nn n 20/S 3S/3 3o/3. 4A41 S* y Wi. ity» ZU/« 23A4~~

~~Figure 6.5. Numbers of Grey Plovers leaving in northerly direction from the Baie d'Aouatif and theNorthwes t Bay.~~

~~NUMBER OF BIRDS~~

~~• JOO~~

~~2oo~~

~~AOO - 1-t~~

~~n n O « 2QÔ 25/3 Jc/3 WO em UJJU \sm m& 2&n~~

~~Figure 6.6. Numbers of Knots leaving in northerly direction from the Baie d'Aouatif and the Northwest Bay.~~

Thetim eo fhig h tidei sthough tt ob eo fimportance ,tha ti sbird s tend toleav ewhe nth etid ei shig h justbefor edark .O n3 0March ,1 4an d 25Apri ldepartur ewa smos t intense.O n3 0Marc hhig h tideoccurre da t 20.25h (AdmiralTid eTables) ,s oth erisin g ofth etid ecoul dver ywel l beo finfluence .However ,o n1 4Apri lth etid ewa slo wa t 15.45h ,s o birdswer e stillfeedin go nth emudflat sa tdusk .O n2 5Apri lhig htid e wasa t 16.50h . Indeed onthi sda yth efirs tfloc klef ta t 15.00h . Although thetid ewa salread ygoin gdow na tdus klarg eflock swer estil l leaving fromhig h tideroosts .Hig h tide justbefor edar ki sprobabl ya favourableconditio nbu tno tth eonl yone . Insam ewade r species likeOystercatcher ,Curle wan dRedshan kth e

~~72 Table 6.1. Data of waders leaving Mauritania from other sites than the Northwest Bay or the Bale d'Aouatif.~~

~~Date Place Time Species Number Direction~~

4 April Nouadhibou 11.00 Redshank 20 N 6 April Nair 17.30 Oystercatcher 55 N 17.45 Curlew 12 N 20Apri l Nalr 17.50 Turnstone 242 N 21 April Nair 16.30 Bar-tailed Godwlt 20 N-NE 16.45 Bar-tailed Godwit 30 N-NE 17.10 Bar-tailed Godwit 40 N-NE 17.45 Bar-tailed Godwit 26 N-NE 17.45 Whimbrel 60 N-NE 1Ma y He d'Arguin 16.30 Bar-tailed Godwit 160 N-NW 17.25 Dunlin 405 N-NW Knot 100 N-NW Bar-tailed Godwit 170 N-NW 17.35 Dunlin 20 N-NW 10Ma y Nouadhibou 15.00 Knot 30 N 17.05 Ringed Plover 12 N

~~NUHeeR OF "fetftPs~~

~~400~~

~~300 _~~

~~Zoo~~

~~-too~~

~~2&3 ess 3Q3 4/~~

~~Figure 6.7. Numbers of Bar-tailed Godwits leaving in northerly direction from the Baie d'Aouatif and the Northwest Bay.~~

73 Table 6.2. Detailed data for the Bale d'Aouatif on the increase and decrease of numbers of waders between the high tide counts on 24March , 17 and 25 April,an d the total number of birds which were seen leaving during these periods.

~~24March-1 7Apri l 17April-2 5 April Species In- De- Visible In- De- Visible crease crease Migration crease crease Migration~~

Oystercatcher 721 1295 51 37 Ringed Plover 29 25 633 - Kentish Plover 406 - 441 - Grey Plover 657 90 188 20 Knot 10219 121 11696 68 Sanderling 37 30 387 - Little Stint 2005 33 722 - Curlew Sandpiper 6281 - 6259 - Dunlin 33162 195 12217 - Bar-tailed Godwit 7565 4 1236 1 Whimbrel 20 5 - - 4 Curlew 79 209 11 - Redshank 2063 385 456 88 Greenshank 113 157 60 63 Turnstone 240 *- 268 —

74 relationbetwee n thedecreas e innumber san d theintensit yo fth evisibl e migrationwa sver yclea r (Table6.2 ,Fig .6. 3an d 6.A).Th enumber so f Redshankfo rexampl edecrease d rapidly between theen do fMarc han dmi d April.Durin g thisperio d thenumber s ofbird swhic hwer enote d tob e leavingwer ehighe r thanbetwee n themiddl ean d theen do fApri lwhe n numbersdecrease d onlya little .Th esam eprobabl y istru efo rGre y Plovers.Howeve rw edi dno tperfor ma hig h tidecoun tafte r 25Apri lt o showth eprobabl edecreas ei nnumber safte r thestron gmigratio no nthi s date (Fig.6.5) . Insom especie s thedecreas ei nnumber s israrel yo rno talway s accompanied byvisibl emigration .I nKentis hPlovers ,Littl eStints , Curlew Sandpipersan dTurnstone sonl yon emigratio n observationwa snote d foreac ho fthe m (Table 6.2).I nKentis hPlover san dCurle wSandpiper s numbersdecrease d bytw othird sbetwee n twoo rthre ehig h tidecounts . Numbersdroppe d significantlyi nWhimbrel san despeciall yKnot san d Bar-tailed Godwitsa ta tim ewit honl yver yfe wvisibl e signso f migration,whil e thiscoul d bever yobviou sa tothe rtimes :o n2 5Apri l 319Knots ,135 5Bar-taile d Godwitsan d 105Whimbrel swer esee nt oleave . Inth epreceedin gmont honl y 189,5 an d 35(Fig .6. 6an d6.7) . InRinge d Ploversan dDunlin s (Fig.6.8 )a stron gdecreas e innumber s wasno taccompanie d bystron gvisibl emigration .Especiall y forthes etw o species thisi si ncontras twit hexperience s inMorocco ,wher e theygav e most frequentnote so nmigratio n (VanBrederod ee tal. ,i nprep.) . Especially inDunlin s thedifferen t situationa tnigh tmigh thav ebee n important,becaus ea tSid iMouss a 72%(n=95 )o fth emigratin g flockswer e heard atnight ,fo rRinge d Plovers thiswa s31 %(n=39 )(Va nBrederod ee t al.,i nprep.) . Thehig h tidecount ssho wtha tmigratio nwa spresen ta s well (Table 6.2).I nsom especie slik eOystercatcher ,Gre yPlover , Dunlin,Bar-taile d Godwitan dGreenshan k (Fig.6.9 )i nwhic hvisibl e migrationca nb ever yobvious ,ver yfe wo rn obird swer esee nleavin g while theirnumber sincreased ,s oth einflu xo fbird scoul d exceedth e numbers ofbird sleaving .I nOystercatchers ,a tth etim ei nwhic h immigration occurred,visibl emigratio nwa sclearl y lesstha na t thetim e between thefirs tan d thesecon dhig h tidecoun twhe nnumber sdecreased . Otherspecie si nwhic hnumber sincrease d likei nCurle wSandpipers , LittleStints ,Sanderlin g andTurnstone s visiblemigratio nwa sinfrequen t anyway.Bird sleavin g fromth eBai ed'Aouati f and theNorthwes t Baywer e heading northo rnorthwest ,s oa tleas twhe nstartin g off theywer e

75 following thecoas tline .Mos t birdswoul d flylo wove r theshebk ao r climb immediately toa heigh t of 100-150m .A t twooccasion sbird swer e flyingver yhig han d probably leftfro manothe r site:20 0Turnstone s flying innortherl ydirectio no n2 0Apri la tNai ran d 62Whimbrel sflyin g inth esam edirectio no n2 5Apri labov e theBai ed'Aouatif .O nonl ya fe w occasions itwa spossibl e tomak eobservation s onth eplumag ean d sexo f theleavin gbirds .I nDunlin sabou ton ethir d (n=43)wer ei nful lsumme r plumageo n2 4Marc han dal lo fthe mo n1 4Apri l (n=30)an d 25Apri l (n=35). InGre yPlover s 14ou to f 16wer eleavin gi nful lwinte rplumag e on1 5April .O n2 5Apri lhoweve r 38%(n=242 )wer ei nsumme rplumage .I n Knotsonl yon e third (n=228)wa si nful lsumme rplumag ea t theen do f April.O fth eBar-taile d Godwits leavinga t theen do fApri l 44%wer e female (n=132).

~~NUMfcER. or ^\RQS~~

~~200~~

~~203 253 3oa 44 ad MA «4 «H*4 t°#\~~

~~Figure 6.8. Numbers of Dunlins leaving innortherl y direction from the Baie d'Aouatif and the Northwest Bay.~~

~~NUMBER OF BlftPS 400~~

~~Joo~~

~~Qoo-~~

~~•100 - n n ÄV3 2£Z3 «y3 4/t* 9*A \ 44 \9/t\ ZH /a ÎAM~~

~~Figure 6.9. Numbers of Greenshanks leaving in northerly direction from the Baie d'Aouatif and theNorthwes t Bay.~~

~~76 WADER CATCHES~~

PietDuive n& Theuni sPiersm a 7.1Methodolog y Normally speaking thisshoul d bea continuou s storyo fcanno nne tcatche s ofhug enumber so fwaders .A sha dbee ndescribe d inth eprojec tproposa l 'largecatche s shouldb eattempte d inMarch ,earl yApri lan d theen do f April'.Enthusiasti c informations byobserver swit hgoo d acquaintance with theloca lsituatio nmad etha tw eha dgoo dhop et orealis ecatche so f largenumber sindeed .Fo rthi sai mw eha d takenfou rcanno nnet swit hus . Twoset so f thetyp e thati sbein guse db yth eWas hWade rRingin gGrou p andanothe r twoset so fth eVogeltrekstation-typ e (Bub 1969)i nus eb y

~~Table 7.1. Numbers of waders captured near Ioulk on the Banc d'Arguln, Mauritania inMarc h and April 1985.~~

~~Species Newly Controls Recaptures Total ringed (foreign) (own rings)~~

Oystercatcher 2 2 Avocet 2 2 Ringed Plover 55 2 57 Kentish Plover 10 10 Grey Plover 13 13 Knot 284 2 287 Sanderling 34 34 Little Stint 169 5 175 Curlew Sandpiper 42 1 43 Dunlin 430 11 442 Bar-tailed Godwit 85 85 Whimbrel 27 27 Redshank 29 1 30 Turnstone 214 10 226

~~Total 1396 32 1433~~

~~77 o i 1 3 um~~

Figure 7.1. Locations where wader catching attempts were made.O n locations 1an d 5onl y mist-netting was done,o n location 3an d 4onl y cannon-netting. On location 6bot h mist-an d cannon-netting was performed whereas on location 2clap -an d cannon-netting was done.Th e star indicates the camp site. theBir dResearc hGrou po fth eNetherland s Instituteo fSe aResearc h (NIOZ),Texel .Th eWash-net swer eunde r supervisiono fMar kFletcher , whereas theNIOZ-net swer ehandle d byPie tDuiven . Toasses sth etota lnumber so fwader si nth eBai ed'Aouati f andi nth e North-west Bayw estarte d counting onth ever yfirs tda yafte rou r arrival.W ethu sgo ta nide ao fth epotentia lcatchin g sitesa tth esam e time.Ther ewer eman yhig htid eroosts ,bu ti nspit eo fth elarg enumber s ofbird san dhar d labouro fth ewhol eexpeditio ntea mw eonl ygo tsmal l catchesof fan don . Severalreason sca nb epointe d outfo rth ecaus eo fthi smeagr e catching results.Th esurrounding s ofth ehig h tideroost swer ei nal l casesver yextensive ,extremel y flatan dmostl ywithou tan y traceo f vegetation.Dependin g onth especie sth ebird srooste d onlan d closet o thewater ,o rjus ti nth ewater .Unfamiliarit ywit hth etida lcurrents , thewate r levelst ob eexpecte d and theeffec to fwin d onthis ,wer ebi g handicaps tofin d theexac tpositio nfo rsettin g thenets .Sometime sth e netswer e flooded,an d sometimes thenet swer efa rou to freac ho fth e water.Ther ewer eals ohig htid eroost si nth emiddl eo fth esebkha . Settingnet sher ewa ssimpl emadnes sMar ktol dus .Bu t ...wedid ,fo ri t

78 wass ofrustratin g tose eal l thebird swithou t anypossibilit y tocatc h them.B yobservin g frequentlywher e theywer egroupin gw e sawthe yfle w andwalke d toth esam earea ,bu t theyneve ruse d exactly thesam espot . Thebird swer eno t shya tal lan dcoul d beapproache d easily.However ,i f theydi dno tg ot oth erigh tplac e (ournets! )directly ,w edi dno t succeed ingettin g themi nfron to fth enet swithi nth ecatchin g distance.W e failednotwithstandin g wellexecute d drivingb y thetea m members,an d thesubtl ecrawlin gaction sb yMar kan dCo r likeskilfu l infantrymen . Theonl y placewher ew ecoul db efairl y suret ocatc hbird swa sth e beacho fth efishin gvillag eo f Iouik.Turnstone san d Sanderlingswer e foragingher eclos et oth ehut so ndryin g fishan d furtheralon gth e beacho ncarrio nan dwer euse d toregula rdisturbanc eb ypeopl ewalkin g around.Wit hfis hremain san dkitche n leavingsw ecoul dlur ethes e species toou rnets . Aproble mno tye tmentione dwa sa mor etechnica l one.Whe nw ewante d tofil lth ecartridge s forth efirs ttime ,Mar kdetecte d thatth epowde r

~~Table 7.2. Numbers of waders (recaptures excluded)capture d with different type of net near Iouik inMarch/Apri l 1985.~~

~~Species Type of net Mist Clap Cannon Total~~

0y6tercatcher 1 1 2 Avocet 2 2 Ringed Plover 46 9 55 Kenti6h Plover 10 10 Grey Plover 11 1 1 13 Knot 268 1 16 285 Sanderling 22 11 1 34 Little Stint 170 170 Curlew Sandpiper 33 9 42 Dunlin 397 34 431 Bar-tailed Godwit 71 14 85 Whimbrel 6 21 27 Redshank 29 29 Turnstone 60 156 216

~~Total 1126 170 105 1401 Total in % 80 12 8 100~~

~~79 Table 7.3. Numbers of waders captured per day (recaptures excluded)nea r Iouik during the study period March (3) -Apri l (4) 1985.~~

~~Date 22/3 23/3 24/3 25/3 26/3 27/3 29/3 30/3 31/3 1/4 2/4 3/4 6/4 8/4 9/4 10/4 11/4 12/4 13/4~~

Oystercatcher Avocet 2 Ringed Plover 6 4 2 1 2 1 1 9 2 3 3 Kentish Plover 2 2 1 1 1 Crey Plover 2 2 1 1 Knot 16 9 2 3 1 18 6 22 16 1 10 17 6 14 Sanderllng 2 1 1 2 2 1 1 Little Stint 7 3 1 1 16 4 7 4 6 7 11 Curlew Sandpiper 1 6 7 4 3 4 2 1 2 I Dunlin 88 3 27 2 18 5 18 27 14 18 4 17 4 6 Bar-tailed Godw. 5 1 3 5 3 15 3 11 4 2 Whlmbrel 1 1 21 1 Redshank. 10 8 1 1 1 1 Turnstone 1 38 22 6 10 3 10 9 20

~~Total* 137 18 10 97 23 36 23 64 47 64 37 37 33 58 23 60~~

~~Date 14/4 15/4 15/4 17/4 18/4 19/4 21/4 22/4 23/4 24/4 25/4 27/4 28/4 29/4 Totals~~

Oystercatch«r 1 2 Avocet 2 Ringed Plover 4 5 1 1 1 4 1 1 55 Kentish Plover 1 1 1 10 Grey Plover 1 1 1 2 1 1 13 Knot 6 23 42 19 5 1 37 3 1 285 Sanderllng 2 3 1 2 5 2 2 34 170 Little Stint 27 37 21 4 12 2 Curlew Sandpiper 1 1 3 1 2 3 42 431 Dunlin 7 64 44 5 22 1 19 5 85 Bar-tailed Godw. 1 12 12 2 6 1 27 Whlmbrel I 1 1 29 Redshank 2 1 1 1 2 14 14 216 Turnstone 7 5 3 1 5 17 27

~~1401 Totals 52 152 132 14 71 8 76 12 17 31 16 21~~

80 PROJECT BANC OARGUIN MAURITANIA | 1 S|)P(.IPS $ SPtClES SITE DAY MONTE- YEAR TIME F RST TIME * S tkime CAPTURE WEIGHT q 1IRST I 1 o O 5 WEIGHT UJ 1 I 1 ce UJ Enring 1rs CE t/3 code I»-, ~3 F? UJ Q_ X < Ct < NUMB 't in Cr. et RING NUMBER ) i • « u o n « « n n ! 1

~~si c» )D n V« WING BILL TOTAL HEAD Till! TARSI) S RltJS PRIMAE~~

~~WEIGHT g SECOND nirn mm nm HEIGHT TOE mm '.M (i ,W1 1. 1 j :>. '? ;t. ',, -1 .».* ') çç CM fi CC WEIGHT mm U.' o O lirs 0 5? UJ P' P? pi p-l P') p»ï p/ pf pi pli Q or <1 n S y •J A JJ U~~

RINGING SCHEME: 01 London, UK PLUMAGE DYE 0 - no dye applied LEGEND BIOMETRY/RINCINC DATA SHEET 02 Washington. USA 1 • picric undcrwing only ) Knot 03 Reykjavik. Iceland 2 * picric on tail .ind/or wing bar ) Sanderling CAPTURE METHOD: 04 St»vanner, Norway 3 - picric both under «nd upp#r-aide) Bar-tailed Codvit 05 A«, Norway > Crey Plover 06 Oilo, Norway ) Rcdshtnk 07 Stockholm, Sweden ) Curlew Sandp.

4 • rhodaminc underwinR only ) SPF.CIES (Euring): 5 - rhodaminc on tail and/or wing bar ) Ringed Plover » 450 Oyitercatcher 81, B1HI 11 Viborg, Denmark 6 - rhodaminc both under and uppcr~iide ) Dunlin (70 Rinsed Plover Bl, TOHE, TATO 12 Kaltf, Denmark 486 Crey Plover BIHE, BI, TOHE, TATO 13 Arnhem, Hol land •96 Knot Wl, TOME, TATO (4 Leiden, Holland «97 Sanderling Bl, TOHE, TATO 15 Helgoland, Germany Mil Litt1 * Stint Bl, TOHE, TATO 16 Radolfzell, Germany 509 Curlwc Sandpiper BI, TOHE. TATO 17 Roasiten, Cemany 5)2 Dunlin BI, TOHE, TATO, race 18 Hiddenaee, Germany 534 Kir-Oiled Codvit BI, TATO 19 Sempach, Switzerland 538 Vhimbrel Bl, TATO 20 Bruxellea, Belgium 539 Curlew Bl, TATO 21 Jersey 546 Redshank BI. TOHE. TATO 22 Paris, France 548 Creenshank WE, UI BI. TATO 23 Aranzadt, Spain 5hl Turn*ton« VE, WI BI, TATO 24 Donana, Spain 25 Madrid, Spain SITE NUMBER: »ee local-reference liât 26 San Sebastian, Spain 27 Oporto, Portugal TIHEfS): in 24 hr», 1/10 hr (e.g. 5-1) 28 Warsaw, Poland 29 Gdanka, Poland ACE: 2 * full-grown 10 Mataulu, Estonian SSR 4 - ^»t year 31 Tartu, Estonian SSR 5 2nd year 32 Riga, Latvian SSR 6 ••2nd year 33 Moscow, USSR 7- 3rd year 34 Praha, Chechoslovakia 8 • »3rd year 35 Budapest, Hungary 36 Sofia, Bulgaria - PLUMAGE Blank • no record 37 Bucarest, Romania 1 - full winter plumage 38 Zagreb, Yugoslavia 7 • trace of summer plumage 39 Bologna, Italy J * ( of luwtr plumage 40 Valetta, M*lta t - , of luMfr plumage 41 Cyprus 5 - 1 of turner pluauft« 42 Tunis, Tunisia 6 - trace of winter plum*** 43 JOB, Nigeria 7 - full summer plumage 4* Nairobi, Kenya 45 Livingstone, Zambia 46 Pretoria. S.Africa

~~BODY MOULT SCORE: Blank - not recorded 1 0 - no moult rd l' °°* 1 - light moult 7 - Mdum~~

~~njt added or replaced TAPE COLOUR: 0 • no tape added or replaced 1 - white 2 - yellow 3 - hlu e 4 - areen~~

~~Figure 7.2. Lay out of the biométrie and ringing data form used on the Banc d'Arguin in 1985 and 1986. The form is based on an earlier one developed by the Wader Study Group (cf. Pienkowski 1980).~~

81 Figure 7.3. Distribution of waders marked between 22Marc h and 18Apri l 1985o n the two mist-netting sites (stars)a s was apparent from resightings of birds foraging on the mudflats in the second half of April 1985. Per area, the percentage of marked birds is indicated. Sample sizes for each area are_ >100 0birds . weha d takenwit hu slooke ddifferen t fromwha th ewa snormall yworkin g with.Afte r somediscussion sa tes tprojectil ewa sfire dwit hgoo d result.Howeve r thecannon slate rrefuse da tth ecrucia lmoment ,s o proving thepowde rproble mwa smor eseriou s thanw eha d suspected initially.Ne wfirin g testsyielde dvaryin g (goodan dbad )results .Mar k therefore returned toNouadhibo uwher eh ecam ei ncontac twit hexplosiv e expertso fa Frenc hminin gcompan yafte rintroductio n byGu yGermain . Withver ypowerfu lexplosive s forus ei nminera lproductio nan dsom emor e explosives outo fa dismantle d Russiandud ,ou rdrive rEl yo /Elemin e safelybrough tbac kMar kafte ra Landrove r tripthroug ha burnin gho t desert.Befor ew estarte d practisingwit h thesedangerou sexplosive ssom e other testswer ecarrie d outwit hou row npowde rfirst .A t lastMar kgo t reproducible correctfiring sb ymixin g thepowde rwit hhead so fth e matchesfro mou rcomba trations . After thisenumeratio no ftroubles ,on eshoul dno tforge t thatw edi d get somebird si nou rhands .Althoug h thenumber swer eno thig hthes ear e listed intabl e7.1 . Mostwader si n198 5(Tabl e7.2 )an di n198 6(all ,excep t forth e

82 Turnstones caughtwit hcla pnet s inth evillage )wer eeventuall ycaugh t withmis tnets .W euse d 15m lon g three shelf 'wadernets 'an d 9m lon g four shelf 'songbird nets'.Line so fnet s totallingbetwee n 150an d40 0 m,mostl y setperpendicula r toth ewind ,wer euse ddurin g thecatchin g nights (whenth ewin dallowe d ust oemplo y thenets) .Figur e 7.1give sa n overviewo fth ecatchin g localitiesuse d in 1985an d 1986.Th enet s becamequickl yver yheav yan d pollutedwit h saltan ddust .I n198 5thi s leadu st owas h thenet shalfwa y through thestud yperio dwit hsom e (non-potable!)fres hwater . Wechecke d thenet s3- 4time spe rnight ,carryin g thebird sfro mth e netst oth eboa to rshor ei nbags .Th ebird swer etransporte d inplasti c cages (ofteni nth eLandrover )bac kt ocam pfo rringing ,measurin gand , in 1985,colour-dye-marking . Captured birdswer eringe d andweighed .I nadditio n lengthso fwin g (maximumchord ;Evan s 1986),bill ,tota lhea d (Green 1980)an d tarsus+ toe (cf.Piersm a 1984)wer emeasured .Bod ymoul twa s scoreda sabsent , light,mediu mo rheavy .Th eexten to fsumme rplumag ewa sindicate d ina sevenpoin t scale ranging from 1= ful lwinte rplumag e to7 = ful lsumme r plumage.Sexin gwa sonl ypossibl ewhe nth ebird sha dattaine d summer plumage toa sufficien t degree.Agein gwa saccordin g toPrate re tal . (1977).Al ldat awer eimmediatel ywritte ndow no ngree n 'computer-ready' forms,o nth ebac k sideo fwhic hal ladministrativ edetail swer egive n (Fig.7.2) .Th edat awer eentere d intoth ecompute rdirectl y fromth e cards (kindlyorganise d byStaatsbosbeheer ,Utrecht) .Mos to fth e analysesreporte d oni nchapte r 9,wer eperforme d usingth e SPSS-statistical package (Niee tal .1975) . Allth ebiométri einformatio n onwader si spresente d inAppendi x1 .

~~83 CM ri CN~~

~~C « U O.~~

5- *

~~u ** m n~~

~~N (Tl sC~~

~~m — CM~~

~~(O ^ CS H N CM •- > a~~

~~-« ^O — —• —• o s~~

~~-* U"l CM~~

~~"-» O. ~ 3~~

~~^ CO -H~~

~~U 3 CD V « 4J •O -t I e ti s â~~

~~«w -o 91 V~~

~~ptf~~

84 TheunisPiersm a& To mM .va nSpanj e 7.2 Capturetotal s In 1985whe nw econcentrate d oncatchin gwaders ,w emanage d tocaptur e 1433bird s (Table 7.1).I n198 6wade rcatchin gha da lo wpriority ,bu t still94 7wader swer ecaugh t (Table 7.5).Amongs t thosecaugh t in198 6 were 30recapture s from theyea rbefore .Dunlins ,Turnstones ,Knot san d LittleStin t contributedmos tt oth ecatchin g totals.A breakdow no f numbers caughtwit hth edifferen t typeso fcatchin ggea r in 1985i s presented intabl e 7.2.Th enumber s caughtpe rda y in198 5ar e listedi n table 7.3.I n 1985w ecolour-dye d thebird san dals opu tcoloure d plastic tapearoun d thering .Thes eactivitie swer ecarrie d outi nth econtex to f theWade r StudyGrou pprogramm eo n 'wadermigratio nstudie salon gth e EastAtlanti cFlyway '(Piersm a 1984).Tabl e7. 4present s thespecie san d numberscolour-marke d indifferen tway si ndifferen t periods.N o dye-marking tookplac ei n1986 ,bu tth emajorit y ofwader sreceive d green-yellowtap earoun d thering .

~~Table 7.5. Numbers of waders captured near Iouik on the Banc d'Arguin in February-April 1986.~~

~~Species Newly Recaptures Recaptures Controls Total ringed within of birds 1986 ringed in 1985~~

Oystercatcher 10 1 11 Ringed Plover 19 19 Kentish Plover 14 14 Grey Plover 8 8 Knot 114 2 116 Sanderling 20 20 Little Stint 104 104 Curlew Sandpiper 48 1 49 Dunlin 348 5 365 Bar-tailed Godwit 30 30 Whimbrel 4 4 Redshank 16 1 17 Greenshank 1 1 Turnstone 161 5 21 189

Total 897 15 30 947 A listo f the 'non-waders'caugh t during thetw oexpedition si s provided bytabl e7.6 . Visual sampling during lowtid e showed that themajorit yo f colour-marked wadersstaye d (foraged)ver yclos et oth ecatchin gsit e beforedeparture :th epercentag e ofmarke d birdso fal lspecie sdecrease d very stronglya son emove dawa yfro mth ecatchin g sites (Fig.7.3) . Observationsmad eelsewher eo nth eBan cd'Argui n (e.g.Nair )i nth esam e period yielded nomarke d birdseither .

Table 7.6. Numbers of birds (non-waders)capture d and ringed near Ioulk In February-April 1985an d 1986.Onl y one bird, aWillo w Warbler, was a control (ringed in Great Britain). The warblers and other non-waterbirds were almost all captured at the campsite with mist nets.

~~Species Numbers ringed in 1985 1986~~

Storm Petrel Hydrobates pelagicus 5 Pintail Anas acuta 1 Kestrel Falco tinnunculus 3 Quail Coturnix coturnix - - Grey-headed Gull Larus clrrocephalus 1 Black-headed Gull Larus ridibundus - 2 Slender-billed Gull Larus genei 45 72 Gull-billed Tern Gelochelidon nllotlca 1 Royal Tern Sterna maxima 2 Sandwich Tern Sterna sandvlcensls 1 Little Tern Sterna albifrons 1 Black Tern Chlidonias niger - 3 Wryneck Junx torquilla 1 - Sand Martin Riparia rlparla 1 - Swallow Hirundo rustlca 24 12 Red-rumped Swallow Hirundo daurica rufula - 1 House Martin Dellchon urbica 1 Tree Pipit Anthus trivialis 1 1 YellowWagtai l Motacllla flava 3 White Wagtail Motacllla alba - 1 Thrush Nightingale Lusclnia megarhynchos 1 - Redstart Phoenlcurus phoenicurus 2 - Whinchat Saxicola rubetra 2 Wheatear Oenanthe oenanthe 2 - Grasshopper Locustella naevla 3 - Savi's Warbler Locustella luscinoldes 1 Reed Warbler Acrocephalus scirpaceus 1 Melodius Warbler Hippolais polyglotta 1 Subaline Warbler Sylvia cantillans 1 Spectacled Warbler Sylvia conspicillata - 1 Common Whitethroat Sylvia communis 2 Garden Warbler Sylvia borin 3 Blackcap Sylvia atricapilla 5 Bunnell'sWarble r Phylloscopus bonelli 2 1 Chiffchaff Phylloscopus collybita 9 25 WillowWarble r Phylloscopus trochllus 49 21 Pied Plycatcher Flcedula hypoleuca 1 Woodchat Shrike Lanius senator 10

~~Total 186 141~~

86 TheunisPiersm a 7.3Resighting san d recoveries Thecolour-markin g programmei n 1985prove d tob ea grea t success:n o less than2 2o fth e 1256(1.8% )colour-marke d birdswer esighte d lateri n theyea r (Table 7.7),thereb y extensively increasing ourpresen t knowledgeabou tmigratio nroute san dbreedin gdestination so fwader s wintering onth eBan cd'Argui n(cf .Engelmoe r 1982).Th eresighting san d recoveries (Table7.8 )o fKnot sconfirme d theexistenc eo fa stopove r sitei nwest-centra l Francefo rKnot swinterin g inWes tan d SouthAfric a andbreedin g inSiberi a (Dicke tal . 1987).Th eresighting so f Sanderlings inth eWadde nSe asugges t aSiberia nbreedin g origin.Th e resightingso fDunlin sar econsisten twit hth evie wtha tmos tDunlin s winteringo nth eBan cd'Argui n areo fth eschinzi i subspecies.Apparentl y bothbird sfro mth emai nbreedin gpopulatio no nIcelan dan da smalle r populationo nth eHebrides ,Scotland ,an d possiblyals ofro m thever y smallBalti cpopulatio nar einvolved .On eCurle wSandpipe rwa sresighte d lateri nsprin go nMalta ,i nth eMediterranean .Thi sresighting ssugges t a trans-Saharanmigratio nvi aTunisi a toth eSiberia nbreedin ggrounds . OneBar-taile d Godwitwa sresighte d onlya wee kafte rcaptur ei nDenmark : thisbir dwa scertainl ya ver yearl ymigrant !Tw oothe rbird swer e resighted ona majo r sitei nth eDutc hWadde nSe a(on eo fthe monl yjus t escaped thenet!) .Th eresighting s ofRedshank ssugges ta Wes tEuropea n breedingorigin .Th ethre esighting so fTurnstone si n198 5ar eremarkabl e since thesebird swer eonl ymarke d withgreen-yello w tape (indeed,th e uniquecolou rcombinatio nmad ei tpossibl e topositivel y identifyth e birdsa scomin gfro mMauritani a inth efirs t place). Iti sstrikin gtha t noTurnstone smarke dwit hgreen-yello wtap ewer esighte d during the198 6 season.Th erecover yo fa Turnston efro mGreenlan d goesagains tal l preconceptions:Mauritania nbird swer ethough t tocom efro mNorther n Europeanan d Siberianbreedin garea sonly .Th erecaptur eo fa Ringe d Ploverdurin g thesam esprin g (1985)nicel y illustrates theus eo f stop-oversites ,an d pointst oa Greenlan d orCanadia nbreedin gorigin .

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~~8. BODY COMPOSITION ANALYSIS~~

NellyE .va nBrederod e 8.1 Introduction Of 85waders ,th eunavoidabl e casualties ofou rmist-nettin gan d cannon-nettingactivitie s in 1985,i twa spossibl e tomak ea bod y compositionanalysis .Twelv e specieswer einvolve d (Table8.1) .

~~Table 8.1. Species and numbers of waders caught at Iouik,Mauritania , and used for body composition analysis.~~

~~Species Number~~

~~Ringed Plover 4 Kentish Plover 1 Grey Plover 1 Knot 23 Sanderllng 1 Little Stint 13 Curlew Sandpiper 2 Dunlin 29 Bar-tailed Godwit 4 Whimbrel 3 Redshank 1 Turnstone 3~~

8.2Method s Freshweight s (ingrams )wer erecorde d aswel la swing- ,bill- ,tota l head-an d tarsus+ to elength s (inmm) . Thepectora lmuscle so f therigh t sidewer e completely removed and theirfres hweigh twa staken .Sternu m

93 measurementswer emad eaccordin g toPiersm ae tal . (1984).Th elatte r data togetherwit h thebreas tmuscl eweigh tca nb euse d tocalculat eth e standard musclevolum e index;a ninde xo fth eprotei nreserves .Ag ean d sexwer edetermine d bydissection .Th ecarcasse san d thepectora lmuscle s weredrie d ina fiel d ovena tc .60° Cfo r 2-4day sdependin g onth esiz e of thebird .Afte rdryin g theywer epreserve d oneb yon ei ntightl y closed plastic bags filledwit h silica-gel.Afte r transportation toth e Netherlands theywer edrie dagai na t thelaborator yan d thedr yweigh t wasrecorded .Fo r theextractio n oflipid spetroleu methe rwa suse d ina Soxhletapparatus .Th eresidua lweigh t ofth ecarcas san dth epectora l musclesafte rfurthe rdryin gwa stake nt ob eth efat-fre edr yweigh t( = leandr yweight) .Th eweigh t ofth efa twa sobtaine d bysubtractin gth e leandr yweigh tfro m thedr yweight .Lea nfres hweigh twa sobtaine db y substracting theweigh t toth efa tfro mth efres hweight .

~~8.3 Results 8.3.1 Water percentage Thepercentag e ofwate ro fth elea nfres hweigh t showsconsiderabl e variationamon gan d between thespecie s (Table8.2) .~~

~~Table 8.2. Mean water percentage of lean fresh weight, standard deviation and range for Little Stints,Dunli n and Knot.~~

~~Species Mean water % Range of lean weight S.D.~~

~~Little Stint (13) 65.3 5.0 53.1-69.2 Dunlin (28) 67.5 3.3 56.9-73.5 Knot (23) 68.8 3.1 58.9-71.8~~

Thesmalle r thespecie sth elowe rth emea nwate rpercentag e (LittleStin t vs.Knot ,t=2.36 ,p<0.05 ,tw oside dStudent' st-test )an d thebigge rth e standard deviation.Thi si si ncontras twit hwinte r figuresfro mth e Netherlandsan dNortheas t Britainwhic h showa rathe rconstan twate r percentageamon g thebird s (Piersma 1984,Davidso n 1981).Th ecaus eo f

94 thisvariatio namon gbird si nMauritani a isno tknown .I tmigh thav e something tod owit h theprocedure s (e.g.th etim ei ttoo kbetwee ndeat h of thebir d andanalyses ;dehydration) . Onewa yo f tellingwhethe rdehydratio nafte rcaptur e iso fimportance , isb ylookin ga tth erelatio nbetwee nwate rpercentag ean d thetim e betweencaptur ean d taking theweigh t (Figs.8.1 ,8. 2 and 8.3).Th e correlationsar elo w(Tabl e8.3) ,bu ti ntw ocase ssignificant ,s oi ti s

**>TEQ% OF FAT FREEWEIGH T

12 3*456?«9-<0'H TIME AFTE.R CATTdJRE., HOUR Figure8.1 . Thewate r percentageo ffat-fre eweigh t of2n dc.y .(•) , adultmal e (*) and adult female (o)Littl eStint s inMarc han dApri li n Mauritania.

possible toestimat eth emea nwate rpercentag ea ttim eo fcaptur ean d makea correctio nfo rbird swit ha lo wwate rpercentage . Awa yo ftellin gwhethe rmigratio ninfluence s thewate rpercentag e isb y lookinga t therelatio nbetwee nth ewate r percentagean d theamoun to f

Table8.3 . Linear regressionso fwate r percentage oflea n freshweigh t (y,ing )o ntim ebetwee ncaptur ean d talcingth eweigh t (x,als oing )fo r LittleStints ,Dunlin san dKnots .Fo rLittl eStint sr i sno t significantlydifferen t fromzero ,fo rDunlin san dKnot sr=0.05 .

~~Species Intercept Slope r 2 r~~

~~LittleStin t(n=13 ) 64.1 0.228 0.11 0.01 Dunlin (n=29) 70.0 -0.613 -0.36 0.13 Knot (n-21) 70.3 -0.405 -0.35 0.12~~

~~95 WATER % OF FAT f^REE U/EK3MT Kl nr O * «o o i * * 6€ o o o 1~~

* 60- 58

~~1 1 12 3HS6'*e34ö'Hl2 TIME AFTER CAPTZJRE, «OOR~~

~~Figure 8.2. The water percentage of fat-free weight of 2nd c.y. (•), adult male (*) and adult female (o)Knot s inMarc h and April in Mauritania.~~

WATER *fc OF BAT FftEE WEKSWT • • n *

~~6% • • • 64 -• •~~

~~56 <23«56?89-K> HOOR TlM e AJFTHÄ CATTURE~~

~~Figure 8.3. The water percentage of fat-free weight of 2nd c.y. (•), adult male (*) and adult female (o)Dunlin s inMarc h and April in Mauritania.~~

96 fat.Recentl yarrive dbirds ,bird si na ba dcondition ,a swel la sbird s whichar eabou t toleav e (premigratorydehydration )migh thav ea lo w waterpercentage .Althoug hbird swit ha lo wwate rpercentag ear eamon g thosewit ha hig hamoun t offat ,ther ei sn o trend (Figs.8.4 ,8. 5an d 8.6).T oge taroun d thepossibl e complication ofdehydratio n thewate r percentageswer eassume d tob e65 %fo rLittl eStints ,66 %fo rDunlin san d 67%fo rKnots .

~~VMTEP, %~~

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~~63 6* 39 5? o 55 S3 o~~

1 2345é"98fl-fO *=ÄT CONTENT,CA Figure 8.4. The relationship between the water percentage of fat-tree weight and the fat content in 2nd c.y. (•),adul t male (*) and adult female (o)Littl e Stints.

~~WAT£R, % ?A~~

~~7o * • O . cw * • • •* o~~

2 4 6 8 10 12 m Ab 18 TS*T COvaTB-flT,< S Figure 8.5. The relationship between the water percentage of fat-free weight and the fat content in 2nd c.y. (•), adult male (*) and adult female (o) Dunlins. 97 8.3.2. Regressions forestimatin g fatreserve s Theregression s forestimatin g thefa tconten t byusin g thefres hweight , and thus thelea nfres hweight ,ar egive ni ntabl e 8.4.I nLittl eStint s thecorrelatio n ishigh .Fo rth esecon d calendaryea r (2nd c.y.)bird s however iti snegative ,bu t therear eonl y threebird san d theyhav ever y

~~Table 8.4. Linear regressions of fat content (y)o n fresh weight(x) . Where n>10, the correlation coefficients are significantly different from zero (p<0.05).~~

~~2 Species Intercept Slope r r~~

Little Stint all birds (13) - 9.5 0.58 0.92 0.85 adults (10) - 8.9 0.56 0.90 0.81 2nd c.y. (3) 5.2 -0.14 -0.97 0.93 Dunlin all birds (28) -14.7 0.48 0.84 0.71 adults (15) - 8.5 0.38 0.69 0.47 2nd c.y. (13) -13.2 0.41 0.87 0.76 Knot all birds (23) -57.8 0.55 0.88 0.77 adults (18) -53.0 0.52 0.68 0.47 2nd c.y. (5) - 5.4 0.08 0.77 0.59

~~Table 8.5. Mean values and standard deviations (in nan)o f wing length, bill length, total head length,an d tarsus + toe length for adultmales , adult females and second calendar year birds.~~

~~Species Wing S.D. Bill S.D. Total S.D. Tars. S.D. length length head + toe length length~~

Little Stint adult females (4) 97.8 3.5 18.3 1.0 39.1 1.4 40.3 2.1 adult males (6) 96.3 2.2 17.8 0.7 38.4 1.3 40.0 1.7 Dunlin adult females (4) 117.3 2.2 31.9 1.9 55.5 1.5 46.8 1.7 adult males (11) 112.2 2.7 27.6 1.4 50.8 1.6 45.6 1.8 2nd c.y. (13) 115.8 3.0 30.6 2.4 53.6 2.7 46.6 1.5 Knot adult females (7) 170.3 3.0 35.0 1.4 63.7 1.9 58.1 1.4 adult males (11) 168.1 3.2 35.0 1.3 62.6 3.4 59.0 1.3 2nd c.y. (5) 164.8 7.2 34.5 1.4 63.1 1.9 58.4 1.5

~~98 Table 8.6. Coefficient of variation (CV)o fwing ,bill , total headan d tarsus + toe length forDunlin s and Knots (CV=S.D./mean).~~

~~Species CV Wing 1. CV Bill 1. CV Total CV Tarsus head 1. + toe1 .~~

Dunlin all birds 0.029 0.087 0.051 0.035 adults 0.030 0.089 0.050 0.039 2nd c.y. 0.026 0.078 0.050 0.032 Knot all birds 0.027 0.047 0.041 0.022 adults 0.019 0.037 0.046 0.022 2nd c.y. 0.043 0.040 0.030 0.026

~~WATER, % 74~~

~~o To o ê o o * * * o o. •o a~~

~~_J 1 l_ I I I I l_~~

~~Figure 8.6. The relationship between thewate r percentage of fat-free weight and thefa t content in 2nd c.y. (•), adult male (*) and adult female (o)Knots .~~

littlefa t(Fig .8.7) .I nKnot san dDunlin sthi scorrelatio ni smuc h lower,especiall y forth eadults .Fo rDunlin s thisca nb eexplaine db y thevariatio ni nsiz ebetwee nth esexe s (Table8.5) .I nKnot showeve r therei sno tsuc ha bi gdifferenc ei nmeasurement s betweenth esexe san d thecoefficien t ofvariatio nfo rbil llengt hi smuc h lower thani n Dunlins (Table8.6) .Secon d yearKnot s likesecon d yearLittl eStint s havever y littlefat .Th eregressio ni sagai nno tver yuseful .I nsecon d

~~99 Table8.7 . Linear regressionso ffat-fre efres hweigh t (Y)o n measurements (x).Wher e r>0.5,th ecorrelatio ncoefficient sar e statistically different fromzer o(p<0.05) .~~

~~Winglengt h Billlengt h Intercept Slope Intercept Slope~~

Little Stintal l 29.2 -0.10 -0.14 35.0 -0.85 -0.36 adults 35.6 -0.16 -0.26 40.8 -1.15 -0.57 Dunlin all - 48.0 0.77 0.48 - 0.7 1.38 0.66 adults -42. 2 0.73 0.58 2.5 1.32 0.75 2ndc.y . -106.0 1.26 0.58 -25. 1 2.11 0.78 Knot all 78.3 0.25 0.12 57.7 1.81 0.25 adults 195.3 -0.42 -0.19 102.8 0.60 0.11

~~Totalhea c length Tarsus+ toelengt h Intercept Slope r Intercept Slope r~~

Little Stintal l 24.2 -0.12 -0.08 19.7 0 0 adults 38.2 -0.47 -0.36 25.1 -0.12 -0.13 Dunlin all -30. 6 1.34 0.69 -41. 7 1.77 0.55 adults -25. 5 1.27 0.77 -19. 2 1.30 0.53 2ndc.y . -58. 1 1.82 0.77 -97. 1 2.93 0.68 Knot all 68.9 0.82 0.23 175.4 -0.93 -0.13 adults 81.7 0.67 0.27 222.5 -1.68 -0.31

~~FATCQKTEMT, g~~

~~1« So 21 11 2$ 2« 2« 26 27 ÎS 29 3d THRESH WEIG.MT, G~~

~~Figure 8.7. Therelationshi pbetwee nth efa tconten tan dth efres h weight in2n dc.y .(•) ,adul tmal e(* ) andadul tfemal e (o)Littl eStint s inMarc han dApri li nMauritania .~~

~~100 FAT CONTENT, G o o n o 28 o » * 24- 20- # *o |6-~~

~~12- o o 6~~

"tOO -MO 120 130 140 1SO 160 PRESM WEIÖ.WT, <5 Figure 8.8. The relationship between the fat content and the fresh weight in 2nd c.y. ( ),adul t male (*) and adult female (o)Knot s in March and April inMauritania .

~~Table 8.8. Lean fresh weight of individual birds and species inwhic h no regression was performed.~~

~~Species Age Sex Weight~~

Charadrius hiaticula adult male 43.8 adult male 50.9 adult male 43.4 2nd c.y. female 43.4 Pluvialis squatarola adult male 175.1 Calidris alba adult female 49.7 Calidris ferruginea 2nd c.y. male 46.3 adult male 52.6 Limosa lapponica adult male 211.9 adult male 265.1 adult male 248.7 adult male 227.7 Tringa totanus adult female 111.1 Arenaria interpres adult male 96.8 unknown female 95.3 adult female 103.1

~~calendaryea rDunlin s theincreas e infa tan dweigh tha s thesam epatter n asi nadults .~~

~~101 FAT CONTENT,~~

~~~~3b35 40<*6 506B6o6s?0 WÏESHWEIGHT, a~~~~

~~~~Figure 8.9. The relationship between the fat content and the fresh weight in 2nd c.y. (•),adul t male (*) and adult female (o)Dunlin s in March and April inMauritania .~~~~

~~~~FAT FREE WEKÄMT ,a~~~~

~~~~O • A9 • o • 46 • 43^ * • * * o 40 * • • * • 3? • • • _ •~~~~

~~~~31 - • 28 -~~~~

~~~~i i ' 1 1 1 I 1 1 1 1 . W SO SI SH 56 58 TOTAL HEAO LEN6TTH, MM~~~~

~~~~Figure 8.10. The relationship between the fat-free weight and the total head length in 2nd cy. (•), adult male (*) and adult female (o)Dunlins .~~~~

~~~~102 Table8.9 . Themea nlea nfres hweigh t ofLittl eStints ,Dunlin san d Knots.Fo rDunlin san dKnot sth elea nfres hweight scorrecte d forweigh t lossafte rcaptur e (cf.Tabl e 8.3)ar eused .~~~~

~~~~Species Meanlea nfres hweigh t (g)~~~~

~~~~LittleStin t (13) 19.7+ 1.8 Dunlin (29) 39.9+ 5.3 Knot (23) 119.7+ 11. 5~~~~

Bothfo rKnot san dfo rLittl e Stintsi ti sno tpossibl e toimprov eth e estimationo flea nfres hweigh tb yusin gothe rbod ymeasurement s (Table 8.7).A scoul d beexpecte d thisca nb edon efo radul tDunlins ,especiall y using bill-o rtota lhea d length (Table8.7 ,Fig .8.10) . Table8. 8 showsth elea nfres hweigh to findividua lbird so fthos e specieso fwhic hsampl esize sar esmall .Tabl e8. 9show sth emea nlea n freshweigh t ofLittl e Stints,Dunlin san dKnots .

8.4 Conclusions Foral lthre especies ,Littl eStint ,Dunli nan dKnot ,fo rwhic h regressionswer epossible ,th ebes testimate so fth eamoun t offa ti n livingbird sca nb ecalculate d fromth efres hweight .Fo rDunlin sa bette r estimation ispossibl efo radult susin gbil llengt ho rtota lhea dlength .

~~~~103 NOXE ON GULLS AND TERNS~~~~

Mark R. Fletcher 9.1 Introduction During thesta ya tIoui ksevera lgull san d ternswer ecaugh tincidentall y inwade rcatches .Althoug hman y specieso fter nwer epresen tan d migrating throughonl yfou rspecie swer ecaugh tan donl y twospecie so f gullwer ecaught .Number so findividual s caughtwer eonl yon eo rtw ofo r allspecie swit h theexceptio no fSlender-bille d Gull (Larusgenei) .O f thisspecie sove ra hundre d individualswer ecaugh tan di twa spossibl e toexamin e thebiométri edat acollecte d forthi sspecies .Som e observations ofcommuna l feedingwer emad e forSlender-bille dGulls .

9.2 Methods Whilst catchingwader si nth evillag eo f Iouikusin ga cla pne tsevera l ofth egull swer ecaugh tincidentall yusuall yattracte d toth ecatchin g areab ybai t laidout .Thi sbai twa srubbis hfro mth evillag ean dbit so f fishthrow nawa yb yth efisherme nwhe npreparin g thefis hthe yha dcaugh t fordrying .Othe rbird sprincipall y ternswer ecaugh ta tnigh ti nmis t netsove r themu dflats .On eter nwa scaugh tb ycanno nne ta si trooste d athigh-tid ewit hwaders . Allgull san dtern scaugh twer eringe dan dbiometric swer erecorded . Thestat eo fmoul tan dplumag ewer erecorded .

9.3Tern s Asman ya seigh tspecie so ftern swer eobserve dan dcounted .Severa l ternswer eobserve d obviouslymigratin g ina stead y streaman dsevera l birdswer eknow nt obree d inth earea ,i nparticula rGull-bille dTern s (Gelochelidonnilotica) ,Caspia nTern s (Sternacaspia) ,Roya lTern s (Sternamaxima) ,Commo nTern s (Sternahirundo )an dBridle dTern s(Stern a

104 anaethetus)(Trotigno n 1976).O nsevera loccasion smixe d flockso ftern s wereobserve d feedingo nfis hshoal seithe rou to nth eope nse ao ri n poolsa to rnea rIoui kwhic hwer efloode da thig htide .

9.3.1 Gull-billed Tern (Gelochelidonnilotica ) Individualsan d partieso fthi sspecie swer et ob esee na tsevera l locationsove r themu d flatsofte nfeedin go nFiddle rCrab s(Uc a tangeri).Th emaximu mnumbe rcounte d athig htid ei nth eBai ed'Aouati f was 191i nlat eApri l 1985.Thi sreflecte d astead ybuil du pfro mnon e counted inlat eMarch .Altenbur ge tal .(1982 )counte d eightbird si n thisarea .Severa lbird swer eobserve dcourting . Onebir dwa scaugh t (18Apri l 1985)an dwa sno taged .N omoul twa s observed.Th e tipo fth euppe rmandibl eo fthi sbir dwa sdistinctl y yellow incolou rcontrastin gwit hth eblac ko fth eres to f thebill .N o broadpatche swer epresent . Measurementsmad ewer ewin g (334mm )an dweigh t (238g) . Fromth e biometricsgive nb yCram p& Simmon s(1983 )i twoul d seemtha tthi sbir d wasprobabl ya nadul tmale .

9.3.2 CaspianTer n (Sternacaspia ) Thisspecie swa sobserve dmigratin g northwardsdurin g theduratio no fth e study.Howeve r therei sa loca lbreedin gcolon yo nKiaon e (Altenburge t al. 1982).Th enumber srecorde d in198 0a tthi scolon ywa s 100-150pairs . Themaximu mcoun tfo rthi sspecie swa s23 4i nlat eApri li nth eBai e d'Aouatif area.Altenbur g etal .(1982 )ha da coun to f39 1i nJanuar y 1980.Dic k (1975)suggeste d anexodu si nlat eOctobe ran d thelat eApri l countma yindicat ebird s returning.N oindividual s of thisspecie swer e caught.

9.3.3 RoyalTer n (Sternamaxima ) Withbreedin gcolonie saroun d theare ao fBai ed'Aouati f fairlylarg e numberso fthi sspecie swer eobserved .Th ehighes tcoun twa si nmi dApri l with73 4individual s counted athig htide .Dic k (1975)suggeste d that birdsma ywinte r toth esout han d thenumbe rcounte d byAltenbur g etal . (1982)i nmi d January 1980gav ea numbe ro f 114fo rth eare amuc hlowe r thanth e36 0counte d sometw omonth slater . Twobird swer ecaugh t together (11Apri l 1985)i nmis tnets .Bot hwer e ageda sadult san dneithe rwer eshowin gwin go rbod ymoult .Dic k (1975)

105 had some 88ou to f 117showin gmoul t inOctobe ran dNovember .I twa s assumed that thesebird swer eo f thesubspecie s S.maxim aalbidedorsalis . Thebiometric swer ea sfollows :win g 374mm/36 2mm , bill 64.1mm/67. 0 mm,tarsu s32. 0mm/30. 8m man dweigh t 410g/39 0g .Th elarge rwin glengt h ismor e thesiz eo f thenominat e subspecies S.maxim amaxim aan di s outside therang erecorde d foralbidedorsali s (Cramp& Simmon s 1983).Th e weightswer ea tth ehighe ren do f therecorde d rangefo ralbidedorsali s but thisma yreflec t thefac t that thesebird swer eperhap sa breedin g pairi nbreedin gcondition .

9.3.4. SandwichTer n (Sterna sandvicensis) Dick.(1975 )suggeste d thata winterin g populationma yb eestablishe di n theBan cd'Arguin .Certainl y roostshav ebee nrecorde db yTrotigno ne t al. (1980)an dAltenbur g etal .(1982 )alon g thecoas to fMauritania .B y mid-March,n olarg enumber so fSandwic hTern swer eobserve dalthoug h therewa sa continuou smovemen t ofbird sapparentl ymigratin g northwards toth eNort hSe acoasts .N olarg enumber swer ecounte da tth ehig htides . Individualso fthi sspecie swer eofte nobserve d sittingamongs troostin g waders. Theon ebir d thatwa scaugh tb ycanno nne t (9Apri l 1985)wa scaugh t withwader sa ton eo fthes eroosts .Thi sbir dwa sage da sa nadult .I t showedactiv eprimar ymoul t similart otha tfoun di nOctobe ran dNovembe r 1973b yDic k (1975). Theprimar ymoul to fthi sbir d showed twowave san d 2 112 13 expressed inth eusua lwa ywa sN 3 4 N 4 0 . Ther ewa sals omediu mbod y moult.Wit ha win g lengtho f30 5mm ,bil lo f55. 1m man dtarsu so f28. 2 mmi twoul d seentha t thisbir dwa sprobabl ya mal e (Cramp& Simmon s 1983).Th eweigh twa s24 2g .

9.3.5 CommonTer n (Sternahirundo ) Aswit hth eSandwic hTer nthes ebird swer eobserve d apparantlymigratin g through thearea .Trotigno ne tal . (1980)reporte d largenumber sfo rCa p Blancbu tAltenbur g etal .(1982 )counte d somea tth eregio no fthi s study.Th emaximu mnumbe rcounte d inth eBai ed'Aouati fwa smi dApri l with 162counte da thig htide .Whe nweathe rcondition swer efavourabl e thesebird swer eofte nsee nfeedin gi nth eshallow san dpool sa sthe y made theirwa ynorthwards .I ti spossibl e thatArcti cTern s(Stern a paradisaea)wer ecounte dwit hth eCommo nTerns .N oCommo no rArcti cTer n werecaught .

106 9.3.6.Littl eTer n (Sternaalbifrons ) Thesebird swer eobserve d apparantlymigratin gnorthward s ofteni n associationwit hCommo nan dSandwic h Terns.Th elarges tnumber s recorded athig htid ei nth eBai ed'Aouati f was6 2i nlat eApril .On ebir dwa s caughtan d itwa sage da sa nadult .N omoul twa srecorded .Th ebiometric s werewin g 172mm ,bil l29. 4m man dweigh t 45.4g .

9.3.7 Othertern s BlackTern s (Chlidoniasniger )an d toa lesse rexten tBridle dTern s (Sternaanaethetus )wer eobserve d flyingthroug h theare ai none so r twos.N olarge rnumbe rwer erecorde d during thehig htid ecounts .Th e BlackTern swer ecaugh t in1986 ,al lwer eage da sadults .Biometric swer e takenan dwer ea sfollows ,al lwer emales : wing (mm) 216 221 223 bill(mm ) 27.3 28.0 27.3 tarsus(mm ) 16.7 18.4 17.5 totalhea d (mm) 60.3 61.2 58.8 weight (g) 61 61 72

~~~~Nomoul twa s recorded.Al lo fthes ebiometric swer esimila r tothos e reported byCram p& Simmon s (1983).~~~~

9.4Gull s Principally four specieso fgull swer eobserve dan dcounte d inth eare a ofBai ed'Aouati f and Iouik.Th emajorit y ofth egull swer efoun d inth e regiono fth evillag eattracte d by thefis hoffa lan d rubbishfoun da t thewater' sedg ean dnearby .A si nEurop eth egull sreadil yconsume d offalan d rubbishwhe ni tbecam eavailabl ean dwaite daroun d feedingonl y forshor ttime srathe rtha ncontinuously .Howeve rsom eactiv efishin gwa s observed andals opirac y ofothe r specieso fgul lan do fwader swa s recorded.Som eo f thespecie so fgul lar eobviousl ymigrant san dcolonie s ofothe r specieswer e found inth earea .

9.4.1 Black-headed Gull (Larusridibundus ) Very smallnumber s of thisspecie swer eobserve d inth eare ao fth estud y aswer e found byDic k (1975)an dAltenbur g etal .(1983) .Thi sare ai s mucha tth esouther n limit ofth erang eo fthi sspecies .I n 1986tw o

107 birdswer ecaptured ,bot hwer e juveniles,i nthei rfirs tyear .Th e biometrics recorded are shownbelo wan dar ewithi nth elimit sa sshow nb y Cramp& Simmon s (1983). wing (mm) 296 285 bill (mm) 34.5 32.4 tarsus(mm ) 44.7 43.3 totalhea d (mm) 80.3 76.6 weight (g) 252 229

9.4.2 Grey-headed Gull (Laruscirrocephalus ) This speciesi sresiden t inth eare aalthoug hn oevidenc eo floca l breedingwa sfound .Thes ebird swer eofte nsee nsittin gan dfeedin gwit h othergul lspecie sa t thevillag eo fIouik .Th elarges tnumbe rcounte d was8 2i nmi dApri lan d thelowes t 22i nlat eMarch .I twoul d seentha t theloca lpopulatio nwa sprobabl ybelo wth ehundred .I nth esam eare ai n JanuaryAltenbur g etal .(1982 )counte d 45:Mos tbird sobserve dwer e comingint osumme rplumag ean d itwoul d seenlogica lt othin kther ewa s somebreedin g inth earea . Onebird swa scaugh t (28Apri l 1985).Fro mth ebiometric s itwoul d seentha t thisbir dwa sa femal ecomin g intoful lbreedin g plumagewit h about threequarter s summerplumage ,ther ebein g lightbod ymoult . Measurementswer ewin g 286mm ,bil l32. 2mm ,tarsu s45. 2m man da weigh t of 260g .

9.4.3 LesserBlack-backe d Gull (Larusfuscus ) Largenumber so fthi sspecie swer ecounte di nJanuar y 1980b yAltenbur g etal .(1982) . Inth eare ao fIoui kan dBai ed'Aouati f 814o fthes egull s wererecorded .Th elarges tnumbe rcounte ddurin g thisstud ywa s2 5i n lateMarch .Th edro pi nth enumber sma yb edu et obird sreturnin gt o restingsite si nEurop ebefor e theMarc hcoun twa smade .Howeve rsinc e 1980an d tosom eexten t beforethi stim eLesse rBlack-backe d Gullshav e lessan d lessbee nmigratin g southwards,particularl y inBritai n (Cramp& Simmons 1985). Insurvey scarrie d outi nEnglan dan dWale sever yte n yearsfro m 1953t o 1983fo rcomparabl earea sth enumbe ro fLesse r Black-backed Gulls inwinte rha srise nfro m 165i n1953 ,696 0i n1963 , 25,057i n 1973an d 44,546i n 1983(Hicklin g 1954,196 7an d 1977;Bowe se t al. 1984). Iti spossibl etha t thenumber so fthi sspecie swinterin gi n Africaha sfalle na sthes ebird shav eno tmove d southwards.Nearl yal l

~~~~108 theLesse rBlack-backe d Gullsobserve dwer eno tful ladult ,man ybein g juveniles.Non eo fthi sspecie swer ecaught .~~~~

9.4.4 Slender-billed Gull (Larusgenei ) Thisspecie si sresiden tan dcomparativel y largenumber swer eobserve d eitherfeedin go nshoal so ffis ho rroosting ,an dfeedin gnea rth e villageo f Iouik.Th ehighes tcoun tmad efo rthi sspecie swa si nmi d Aprilwit hnearl y twoan da hal f thousand counted (2435).Thi swa smor e thanth etota lcoun tfo ral lth eBan cd'Argui nmad eb yAltenbur ge tal .

~~~~Table9.4.4.1 . Meanvalues ,standar ddeviation san d rangeso f measurementsan dweight so fSlender-bille dGulls .~~~~

~~~~Lengthi nm m S.D. Range~~~~

~~~~Wing (n=122) 293 12.5 256 -322 Bill (n=118) 41.6 2.6 35.9-48. 3 Tarsus (n=99 ) 50.0 2.8 42.7-57. 2 Totalhea d (n=98 ) 91.9 4.5 83.6-101.9~~~~

~~~~Weighti ng (n=135) 286.6 38.5 205-404~~~~

(1982)i n1980 .I nth eare ao fBai ed'Aouati fan d Iouiki nJanuar y 1980 theycounte d 218.I twoul d seemtha tbird sprobabl ycom eint oth eare at o breed during thesprin gan dalthoug h thecoun tfel lt o1,66 6 inlat e Aprilthi sma yrepresen tbreedin gbein gunde rwa ywit hon eo fth epai r beingabsent .Th emajorit yo f thebird swer ecounte d onZira . A totalo f5 1Slender-bille d Gullswer ecaugh tan dmeasure d in198 5 anda furthe r 75wer ecaugh ti n198 6whic hinclude d threebird sretrappe d from thesecaugh ti n 1985.Th emajorit yo fbird swer eadults .I n198 5on e firstyea rbird swa scaught ,1986 ,1 4wer efirs tyea rbirds . Theoveral lmea nmeasurement san d rangesar egive ni ntabl e9.4.4.1 . Thehighe rend so fth eweigh t rangear ewel love r thepublishe d weights forth especies ,35 0g (Dement'ev& Gladko v 1951)bu ton eo rtw oo fthes e birdswer efoun d tohav ebroo d patchesan d thehighe rweight sma ywel l havebee nfemale swhic hwer eabou t tola yeggs . Someobservation swer emad eo nth efeedin go nshoal so ffis hb ythi s

109 species.Feedin g bythi smean swa smainl ycarrie d outi nshallo wwate ra t high tideusuall ya ton eo rtw osites ,th esam esite sbein guse da teac h successivehig h tidedurin gdaylight .A tabou t twohour sprio r toth e high tidebird swoul d arrivei npair san ddefen da spac earoun d thepair . Theaggressiv e posturewa stypicall ynec kextende da sa nintrudin gbir d neared toth espac earoun d thepair .Submissiv eposture ,nec khel drigh t down,i softe ngive nb y theothe ro fth epai rwhe nth eaggressiv epostur e isstruck .Som ebird swoul d sito nth ewate ri npairs ,other so nth esan d oftensittin g rightdown .Preenin g occursregularl yan dofte nth elarge r birdo fth epai r- possibl y themal e- calls ,startin gwit hth ebil l pointingdownward san d thenextentin g itupwards .Bot hmember so fth e pairwil lchas eof fa nothe rbir dgettin g tooclose .Pair stogethe ro n thesan dofte nsi twit hthei rbodie stouchin geac hother . Ashig h tideapproache san d theshoal so fsmal lfis happea r thebird s surround theshoa lan d therei sa frenzie d feedingactio nwit hgull s pickingou tth efis hb yplungin g intoth eshoa lo rdippin g toth esurfac e and seizingth efish .Thes ebout so ffeedin glaste dabou t0.7- 2min ,th e birdsusuall y restingo nth esurfac eo fth ewate runti lth enex tbou t started.Bout so ffeedin goccu rabou tever y 3-10min .Th esucces srat eo f observed gullscatchin g fishwa sabou t 10%o fth eplungin gendin gi na fast shallowo fa fish .Som efis hwer ecollecte d froma capture dgul l which regurgitated.A tota lo f 19fis hwer ecounte dgivin ga tota lweigh t of3 0g .Eac hfis hweighe dabou t1.4-2. 1g .Th elengt ho fth efis hwer e allabou t 60mm .Th efis hha sno tye tbee nidentified .

~~~~110 ÏO. AVIFAUNA~~~~

~~~~CorJ . Smit,Abo uGuey e& To mM .va nSpanj e~~~~

10.1 Introduction Thischapte r summarizesal lobservation so fbird san dmammal si n Mauritania during thesta yo fth eexpeditio nmember sfro m 10March- 5Ma y 1985an dfro m 3February-2 8Apri l 1986.Som eadditiona lan dmor e occasionalobservation so fth eprojec tco-ordinato routsid e theseperiod s areadde da swell .Th elocatio no fth esite smentione d inth etex tca nb e found inappendi x 2o f thisreport .Apar tfro moccasiona lobservation so f theexpeditio nmembers ,th eresult so fcount so f theBai ed'Aouatif , EbelkAizna ian dL aCherka ,Nouadhibo ufo reac hspecie sar eadded . Results forth eBai ed'Aouati f includebir dnumber s found inEbel kAizna i and theare aaroun d thevillag eo fIouik .Thi schapte radditionall y includesth ebiometric s ofpasserine scapture d inth eexpeditio ncam pa s wella sbiometric so fsom enon-passerin e speciescapture d occasionally. Fati npasserine swa sscore d 0-5,accordin g toth estandar dmetho d described byBuss e& Kani a (1970).Thi smetho d yieldswel l reproduceable informationo nth eactua lfa tloa do fpasserine s (Pettersson& Hasselquist 1985).Mor edetaile d accountso nth eresult so fcatche so f waders,gull san d ternsca nb efoun d inchapte r 10an dappendi x 1o fthi s report. Abbreviations used inthi schapte r standfor : ad.= adult(s ) camp =bas ecam po f theexpeditions ,approximatel y 500m eas to fth e Biological Stationnea r Iouik JJ= North(ern ) c.y. =calenda ryea r E= East(ern ) imm.= immature(s ) S= South(ern ) juv.= juvenile(s ) W= West(ern )

111 Symbolshav e thefollowin gmeaning : + 1-10 ++11-10 0 +++ 101-1000 ++++1001-1000 0 Systematic order,scientifi cnomenclatur ean dEnglis hname sfo rbird s were takenfro mVoou s (1973,1977) .Frenc hname swer etake nfro m Etchécopar& HU e (1964). Nameso fsom etropica lspecie swer e takenfro m Lamarche (1987). Scientifican dEnglis hname s formammal swer e takenfro m Rosevear (1969).

~~~~10.2Lis to fobserve d bird species~~~~

Tachybaptus ruficolliß LittleGreb e Grèbecastagneu x TheN subspecies ,T.r .ruficollis ,i sa noccasiona lvisito r toth eN par t ofMauritania ,th eS subspecies ,T.r .capensis ,i soccurrin g insmal l numbersi nth eextrem eS par to fth ecountr y (Browne tal . 1982,Lamarch e 1987). Considering thetim eo fth eyea ran d thelocatio no fth esightin g iti smos tprobabl eou robservatio nconcern sT.r .ruficollis .Altenbur g etal .(1982 )observe d 3Littl eGrebe sa t theBan cd'Argui n duringth e 1980expedition . 10/2/866 N par tBai e d'Aouatif

~~~~Podicepsnigricolli s Black-necked Grebe Grèbeà co unoi r Occasionalvisito rt oMauritani a (Lamarche 1987). 15/3/863 nea rcam p (inintermediat eplumage )~~~~

~~~~Oceanitesoceanicu s Wilson's StormPetre l Pétrelocèanit e Visitor insmal lnumber st oMauritania ,occurrin g throughout theyea r (Lamarche 1987). 5/2/86mor e than 100N o fCa pTafari t~~~~

Hydrobatespelagicu s StormPetre l Pétreltempêt e Frequently observed inMauritania ncoasta lwaters ,mostl yfro m March-August (Lamarche 1987). 20/3/85Abou t 10Bai ed eLévrier ;abou t 15nea rCa pTafari t 5/2/86 ++betwee nNouadhibo uan dIoui k 24/4/86+ +betwee n Iouikan d He d'Arguin

~~~~112 Table 10.1Weigh t (g)an dbiometrlca ldat a (mm)o fStor mPetrel scapture d inmistnet s inth eBai ed'Aouati f date weight age wing bill tarsus~~~~

~~~~23/3/85 230 2nd c.y. 119 12.6 22.5 1/4/85 222 2ndc.y . 123 3/4/85 255 2nd c.y. 119 12.0 22.9 15/4/85 274 2ndc.y . 121 12.4 24.6 16/4/85 239 2nd c.y. 120 11.8 22.0~~~~

Sulabassan a Gannet Foud ebassa n Commonvisito r toMauritania ncoasta lwaters ,locall y inlarg eflocks , mostnumerou sfro mDecember-February .Juvenil epercentag egenerall y 50-80% (Lamarche 1987).Altenbur g etal .(1982 )observe d 30Gannet si n theBai ed eLévrie ro n8 Marc h1980 . 10/3/853 ove r seanea rCansad o 20/3/85+ +Bai ed eLévrier ,approx .25 %adult s 13/3/85abou t 50nea rCa pBlanc ,nearl yal limm . 2/5/85 2Bai ed eLévrie r 5/2/86 200-300durin gcrossin g ofBai ed eLévrier .I nth eN par tmainl y adults,i nth eS par tmainl y 2nd c.y.an dimm .I na sampl eo f 21bird s6 ad.,1 4-5t hc.y. , 34t hc.y. , 53r dc.y .an d 62n d c.y.. 25/4/86-H -betwee n lied'Argui nan dNouadhibou ,especiall y inth eW par t of theBai ed eLévrier ,80-90 %imm .

Phalacrocoraxcarb olucidu s Cormorant Grandcormora n TheW Africa nsubspecie so f theCormoran t isa commo nvisito ran d breeding bird inMauritania ncoasta lwater san d theSénéga ldelt a (Lamarche 1987).Altenbur g etal .(1982 )counte d 9395Cormorant s atth e Bancd'Argui n during the 1980expedition .I ti sbreedin ga t theBan c d'Arguin in3 colonie s (4260pair si n 1984-85)fro m September-March (Campredon 1987). 11-13/3/852- 5L aCherka ,Nouadhibo u 15/3/857 L aCherka ,Nouadhibo uan d 23alon gbeac hN o fNouadhibo u 20/3/85+ +are aaroun d CapTafari t 24/3/8530 8Bai ed'Aouati f

113 20-22/4/85+4 -restin gNai rdurin ghig htid e 16/4/85 158Bai ed'Aouati f 23/4/85+ S par to fNiroum i 24/3-7/5/86 16-90Ebel kAizna i 24/4/8528 7Bai ed'Aouati f 2/5/85 25Ca pSt .Ann e 5/5/85 3L aCherka ,Nouadhibo u 22/1-3/2/86 2-3L aCherka ,Nouadhibo u 8/2-22/2/8670-10 4Ebel kAizna i 24/4/86-H -Kiaon e 25/4/865 0W par t He d'Arguin;3 0L aCherka ,Nouadhibo u

~~~~Table 10.2Weigh t (g)an dbiometrica ldat a (mm)o fa Cormoran tcapture d inmistnet s inth eW par to fth eBai ed'Aouati f date weight wing bill tarsus~~~~

~~~~26/3/86 1156 314 63.5 67.2~~~~

Phalacrocoraxafricanu s ReedCormoran t Cormoranafricai n Commonvisito ran dbreedin g bird inMauritania ncoasta lwater san dinlan d habitatsalon g theSénéga lrive r (Lamarche 1987).Altenbur ge tal .(1982 ) counted 7787Ree dCormorant sa t theBan cd'Argui n during the198 0 expedition.Th especie si sbreedin ga t theBan cd'Argui n in2 colonie s (2460pair si n 1984-85)fro mMay-Octobe r (Campredon 1987). 21/3/855 Te nAllou l 24/3/8592 0Bai ed'Aouati f 5/4/85 500Ebel kAizna i 12/4/85mor e than 150fro mEbel kAizna iflyin gtoward sZir a 14/4/85 119Ebel kAizna i 16/4/85 158Bai ed'Aouati f 21/4/854 Nai r 22/4/859 5Ebel kAizna i 23/4/85++ +Niroum i 24/4/8528 7Bai ed'Aouati f 27/4/854 0Ebel kAizna i 8/2/86 280Ebel kAizna i

~~~~114 13/2/8620 3Ebel kAizna i 22/2/8637 2Ebel kAizna i~~~~

Pelecanusonocrotalu s WhitePelica n Pélicanblan c Commonvisito ran dbreedin g bird inMauritania ncoasta lwater san dinlan d habitatsalon g theSénéga lrive r (Lamarche 1987).Altenbur g etal .(1982 ) counted 611adul tWhit ePelican san d 300fledgling sa tth eBan cd'Argui n duringth e 1980expedition .Breedin ga tth eBan cd'Argui n in1 larg e colonya tAre l (3080pair si n 1984-85)fro mSeptember-Marc h (Campredon 1987). 24-25/3/85 1Bai ed'Aouati f 3/4/85 1ad .Ioui k 4/4/85 1ad .Ebel kAizna i 5/4/85 3Bai ed'Aouatif ,S o fcatchin g site5 8/4/85 15flyin g Sove rEbel kAizna i 11/4/854 8(ou to fwhic h 5imm. )passin g Iouik 14/4/85 1swimmin gunde rmistnet s Baied'Aouatif ,sit e5 15/4/85 1feedin go nth eemerge dmudflat san d seagrassbed si nth eN par t of theBai ed'Aouatif ,eatin glarg eprey s 16/4/856 Bai ed'Aouatif ; 1unde rth emistnet s bynight ,Bai ed'Aouati f site5 18/4/852 nea rcam p 20/3-22/3/85u pt o5 restin gdurin ghig htid ea tNai r 24/5/85 13Bai ed'Aouati f 30/4/85 1nea rcam p February-April 1986frequentl y 1-3nea r thecam pan delsewher e inth e Baied'Aouatif .Additiona lobservations : 16/2/865 S Ecorne rBai ed'Aouatif , 2i nth ecentra lpar t 18/2/86 10 S of Zira 19/2/86+ +nea rcamp ,migratin gS 22/2/86+ +Serini ;++ +S Epar tTidr a 24/2/865 Serin i 25/2/86 100S ti pTil apenisul a 2/3/86 10nea r camp,flyin gS 20/3/865 0circlin ghig hove rIouik ,descendin g intoth eBai ed'Aouati f 23-25/3/8620-3 0betwee n Iouikan dRgueïb a 1/4/86 4Zira ;3 Serin i 2/4/86 1N par tTidr a

~~~~11: 8/4/86 9nea r camp,1 Zir a 12/4/86 4migratin g SEbel kAizna i 24/4/864 0surrounding sIoui k~~~~

Nycticoraxnycticora x NightHero n Héronbihorea u Locallybreedin gan dwinterin galon g theSénéga lrive ran di nothe r freshwaterwetland s inS Mauritania .Passin g throughi nautum nan dsprin g and inthes esituation sals oobserve dalon g thecoas t (Lamarche 1987). Altenburg etal .(1982 )observe d 2Nigh tHeron s inNouadhibo udurin gth e 1980expedition . 11/3/85 1imm .i nshi pwreckag eL aCherka ,Nouadhibo u 2/4/85 1ad .beac hIoui k 3/4/85 flyingove r 10Bai eSt .Jea n 5/4/85 3Nai r 23/4/85 1ad .Niroum i 13/4/864 ad .Nai r

Bubulcusibi s CattleEgre t Hérongarde-boeuf s Locallya commo nvisito r toth eS par to fMauritania ,generall yno t comingN o fth e 17thdegre eo flatitude .Smal lnumber sar eobserve di n theN par to f thecountry ,generall yfro mOctober-Ma y (Lamarche 1987). Altenburge tal .(1982 )frequentl y observed someten si nNouadhibo u during the 1980expedition . 11/3/85abou t 10L aCherka ,Nouadhibo u 15/3/853 0S par tPresqu'îl ed eCa pBlan c 1/4/85 1nea rcam p 15/4/85 1Bai ed'Aouatif ,sit e 1flyin gN 3-5/5/851 L aCherka ,Nouadhibo u 22/1/861 L aCherka ,Nouadhibo u 3/2/86 25L aCherka ,Nouadhibo u 3/3/86 over 100L aCherka ,Nouadhibo u

Egrettagulari s WesternRee fHero n Aigrettede srécif s Thesystemati cpositio no fEgrett agulari san dE .garzett a stilli s somewhat obscure.Cram p& Simmon s (1977)obviousl ydistinguis htw o species,bot hhavin ga dar kan da whit emorph .Hancoc k (1984) distinguishes threesubspecie so fE .garzetta ,includin gE.g .garzett a andE.g .gularis ,whit eo rnearl ywhit ebird sbein g 'veryrare 'o n

116. West-African coasts.Brow ne tal . (1982)agai nseparat eE .gulari san dE . garzettaa sseparat e species,bot ho fthes eoccurrin g alongth e Mauritaniancoast .I nth efiel da distinctio nbetwee n thetw o 'species' isver ydifficul t tomake .Fo rpractica l reasonsal ldar kcoloure d egrets wereconsidere d tob eE .gularis ,al lwhit ebird s tob eE .garzetta .Thi s mayhav elea dt oa underestimatio n ofth enumber s ofE .gularis .Th e 'species'i sbreedin ga tth eBan cd'Argui n in8 colonie s (745pair si n 1984-85,5 5o fthes ea tZira )fro mApril-Novembe r (Campredon 1987). Altenburg etal .(1982 )counte d 2899dar kheron sa tth eBan cd'Argui n during the 1980expedition . 11/3/85abou t 10L aCherka ,Nouadhibo u 15/3/85 1L aCherka ,Nouadhibo u 24/3/855 3Bai ed'Aouati f 4/4/85 20Ebel kAizna i 7-8/4/85 1-2Ebel kAizna i 12/4/856 flyin gN an d 3foragin gIoui k 13/4/852 2flyin gN an d 3foragin gIoui k 14/4/852 0i nmixe d flockwit hE .garzett apassin gcam pflyin gN ;i nth e evening 31flyin gS toward scommuna lnocturna lroos t 16/4/857 5Bai ed'Aouati f 20-22/4/85abou t 20a thig htid eroost ,Nai r 22/4/85-H -Ioui k 23/4/85 ++Niroum i 24/4/8521 7Bai ed'Aouati f 1/5/85 + lied'Argui n 3/5/85 1Presqu'îl ed eCa pBlan c 5/5/85 1L aCherka ,Nouadhibo u 7/5/85 2Ebel kAizna i 10/5/852 L aCherka ,Nouadhibo u 22/1-3/2/862- 4L aCherka ,Nouadhibo u 8-22/2/869-2 1 EbelkAizna i 3/3/86 15-20L aCherka ,Nouadhibo u 24/3/86-H -betwee n Iouikan dKij i 25/3/865-1 0betwee nRgueïb aan dSerin i 5/4/86 7i na flock ,possibl ymigrants ,N par tBai ed'Aouati f 24/4/862 L aCherka ,Nouadhibo u

117 Egrettagarzett a LittleEgre t Aigrettegarzett e Sincea distinctio n betweenEgrett agarzett aan dE .gulari s isver y difficult tomak eal ldar kcoloure d egretswer econsidere d tob eE . gularis,al lwhit ebird sE .garzetta .Thi sma yhav e lead toa n overestimation of the realnumbe ro fLittl eEgrets .Twent ywhit eEgret s inL aCherka ,Nouadhibou ,whic hwer ecarefull y studied on2/3/86 ,al l showed typicalcharacteristic s ofRee fHeron slik edul lyello wfeet .Als o at theBan cd'Argui n thisma yhav ebee nth ecase .Onl yon ebir d inIoui k showed clearyello wfeet .Fo rfurthe r comments seeunde rE .gularis . Altenburg etal .(1982 )counte d 2711whit eheron sa t theBan cd'Argui n during the 1980expedition . 11/3/85abou t 10L aCherka ,Nouadhibo u 15/3/85 13S par tPresqu'îl ed eCa pBlan c 5/4/85 1Ebel kAiznai ;1 nea rcam p 10/3/85 1flyin gN ,Ioui k 24/3/85 11Bai ed'Aouati f 13/4/85floc ko f6 2leavin g theBai ed'Aouati f inN directio n 14/4/855 0i nN par to fBai ed'Aouatif , 10i nmixe d flockwit hE .gulari s flying inN direction ;5 5leavin g theN par to fth eBai ed'Aouati f inNN W directiona t 7.35 p.m. 22/4/852 flyin gN ove r seanea rIoui k 23/4/85+ Niroum i 1/5/85 + He d'Arguin 3/5/85 10Presqu'îl ed eCa pBlan c 5-10/5/853- 6L aCherka ,Nouadhibo u 3/2/86 3L aCherka ,Nouadhibo u 8/2/86 5Ebel kAizna i 10-11/2/865- 6 Baied'Aouati f 13/2/86 16Ebel kAizna i 18/2/867 Bai ed'Aouati f 22/2/862 Ebel kAizna i 24/2/86 1Ioui k 3/3/86 -H-L aCherka ,Nouadhibo u 18/3/86 1Bai ed'Aouatif ,sit e 1,attacke d bya Mars hHarrier .On eothe r corpsefound ,apparentl ykille d bya predator . 24/3/86+ +betwee n Iouikan dKij i 25/3/865-1 0betwee nRgueïb aan dSerin i

118 Ardeacinere a GreyHero n Héroncendré e At theBan cd'Argui n2 subspecie sar eobserved .Th eN subspecie s 'cinerea'i sa rathe rcommo nwinte rvisito rfro mSeptember-Apri li n coastalan d freshwaterhabitat sal love rMauritania ,th eendemi c subspecies 'monicae'i srestricte da sa breedin gbir d toth eBan c d'Arguin butma yals ob esee na sa migran t inth eSénéga ldelt a (Lamarche 1987).Th elatte r subspecies isbreedin ga t theBan cd'Argui n incolonie s atKiaon ean dAre l(240 0pair si n 1984-85)fro mApril-Januar y (Campredon 1987).Mos tobservation sconcer n thesubspecie s"monicae" ,thoug hlocall y (andmor eofte ntha nindicate dhere )als oth esubspecie s"cinerea "wa s observed.Altenbur ge tal .(1982 )counte d 3076Gre yHeron sa t theBan c d'Arguin during the 1980expedition . 11/3/85+ +L aCherka ,Nouadhibo u 15/3/854 2S par tPresqu'îl ed eCa pBlan c 24/3/85 172Bai ed'Aouati f 14/4/851 2Ebel kAizna i 16/4/8510 4Bai ed'Aouati f 20/4-22/4/85abou t 10Nai r 22/4/85+ +Ebel kAizna i 23/4/85++ +Niroumi ,amon gwhic hals oA.c .cinere a 24/4/868 3Bai ed'Aouati f 27/4/85 14Ebel kAizna i 1/5/85 ++ He d'Arguin 3/5/85 28S par tPresqu'îl ed eCa pBlan c 7/5/85 4Ebel kAizna i 10/5/851 2L aCherka ,Nouadhibo u 22/1/863 L aCherka ,Nouadhibo u 3/2/86 20L aCherka ,Nouadhibo u 8/2/86 7N par tBai ed'Aouatif ; 20Ebel kAizna i 10-22/2/86 24-25Ebel kAizna i 23/2/86 120S ti pTidr a 25/2/865 0a thig htid eroos t Sti pTil apeninsul a 3/3/86 10L aCherka ,Nouadhibo u 18/3/861 Ebel kAiznai ,positivel yA.c .cinere a 21/3/86 18Bai ed'Aouatif ,sit e 1migratin gS 23/3/862 "cinerea "Bai ed'Aouati f 24/3/86 2"cinerea "betwee n Iouikan dKij i 25/3/86ten sbetwee nRgueïb aan dSerin i

~~~~119 26/4/86+ L aCherka ,Nouadhibo u~~~~

Ardeapurpure a PurpleHero n Héronpourpr é Migrant inrathe rsmal lnumber s (September-November andApril-June )an d winter visitor,especiall y ininlan dwetland si nS Mauritania .Fe w observations from thecoas t (Lamarche 1987). 1/4/85 1Niroum i 5/4/85 14Zir a 23/4/855 Niroum i 22/2/862 Ebel kAizna i 18/3/86 1Ebel kAizna i 20/3/865 i nmangrove sW o fTidr a 13/4/862 juv .an d4 ad .mangrove sW o fTidr a

Ciconiaciconi a White Stork Cigogneblanch e Wintervisito r insmal lflock si nwetland s inS Mauritania .Irregula r passageove r theSahar ai na broa d front,notabl yfro mAugust-Novembe r and inMarch-April ,somewha tmor enumerou s inth eW par t of thecountr y (Lamarche 1987). 10/3/85 1L aCherka ,Nouadhibou ,2 circlin g overNouadhibo u 12/3/85 2L aCherka ,Nouadhibo u 15/3/852 alon g thebeac hN o fNouadhibou ;4 imm .N o fNouadhibo uairpor t 28/4/85 2ad .o nrubbis hti pnea rCa pBlan c 25/1/862 circlin gove rL aCherka ,Nouadhibo u inN directio n

Platalealeucorodi a Spoonbill Spatuleblanch e Twosubspecie s canb enote da tth eBan cd'Arguin .P.l .leucorodi a isa migrantan dwinte rvisito ri nsmal lnumbers ,o nth ecoas ta swel la si n inlandwetland si nMauritania ,arrivin g fromAugus t toNovembe ran d leavingfro mFebruar y toMay .Th esubspecie s"balsaci "i sendemi c forth e Bancd'Arguin .Bird so f thelatte rsubspecie sar eleavin g thebreedin g groundsfro mOctober-Novembe r and returnfro mFebruary-Marc h (Lamarche 1987).P.l .balsac ii sbreedin g atth eBan cd'Argui n in6 colonie s (1610 pairsi n 1984-85,45 0o fthes ea tZira )fro mMarch-Novembe r (Campredon 1987). Bothsubspecie spartl yca nb eseparate d inth efield .Durin gth e 1985/86expeditions ,however ,n oattempt shav ebee nmad et oreall yd oso . Altenburg etal .(1982 )counte d 8991Spoonbill sa t theBan c d'Arguin during the 1980expedition .

120 10/3/85 1L aCherka ,Nouadhibo u 13/3/85 1circlin g overNouadhibou ,2 i nlagoo nN o fNouadhibo u 14/3/856 L aCherka ,Nouadhibo u 15/3/852 9S par tPresqu'îl ed eCa pBlan c 21/3/855 Te nAllou l 23/3/85 1foun ddea d 100m E o fIoui k 24/3/85 1043Bai ed'Aouatif ,tw oo fthes ecarryin gDutc h ringsbu tno t identifiable 1/4/85 24N par tBai ed'Aouatif ,migratin g NNW (7.10p.m. ) 4/4/85 46Ebel kAizna i 5/4/85 40-50Ebel kAizna i 7/4/85 36flyin g towards theemergin gmudflats ,Zir a 16/4/8584 3Bai ed'Aouati f 20-22/4/85colon y settlingdow no nN Wpar tNair .O n21/ 493 0sitting , fighting,copulatin gan dnestin gbird san dabou t 600spectators .Amon g thelatte rbird s 1o r 2carryin gDutc hrings . 22/4/859 flyin gN an d leaving theBai ed'Aouati f around 19.30h ,sit e1 ; 7 foraging therealready ;n olarge r flockspresen tan ymor ei nth eBai e d'Aouatif 23/4/85++ +Niroum i 24/4/859 N par tBai ed'Aouatif ,migratin gNN W (7.30p.m. ) 27/4/853 4Ebel kAizna i 3/5/85 16Presqu'îl ed eCa pBlan c 7/5/85 25Ebel kAizna i 10/5/858 L aCherka ,Nouadhibo u 22/1-3/2/86 1L aCherka ,Nouadhibo u Februaryan dMarc h 1986frequen t observationso fsmal lflock s (upt o35 ) inman yplace si nth eBai ed'Aouatif . 8/2-13/2/865- 7Ebel kAizna i 9/2/86 20o nhig htid eroos tEbel kAizna i 10/2/869 migratin gN i nN Wpar tBai ed'Aouati f 14-19/2/86 200Zir a 16/2/86 150S Epar t Baied'Aouati f 19/2/8620 0o nZira ;anothe r 100Ioui k 21/2/8620 0S Fou mA lTriqu e 23/2/86 150S ti pTidr a 24/2/865 0S ti pAjoueï r 25/2/86200-30 0S Epar t Baied'Aouatif ; 250a t roost Sti pTil apenisul a

.21 28/2-1/A/86 300-400Zir a 3/3/86 1ad .an d 5imm .L aCherka ,Nouadhibo u 18/3/862 0Ebel kAizna i 24/3/86som ehundred sbetwee n Iouikan dKij i 25/3/86+ +betwee nRgueïb aan dSerin i 7/4/86 about 500a tan daroun dAre l 9/4/86 200-300o nhig h tideroos tN Wpar tTidr a 11/4/86-H- +aroun dArel ;++ +Nair ;30 0Giben e 16/4/86 25Kiaon e 20/4/86 135N o fSerini ,a tleas t 2o fthes ecarryin gDutc hrings ;2 9N W partBai ed'Aouatif ,amon gwhic h 5wit hcolou rring s 21/4/86 15N Wpar t Baied'Aouatif ,non ewit hring s 24-25/4/86+ He d'Arguin

Phoenicopterus ruber GreaterFlaming o Flamantros e Presenta sa breedin g birda swel la snumerou smigrant .Th eBan c d'Arguin isth emos t importantwinterin g sitei nMauritania ,sometime s2-500 0ar e wintering inth eSénéga ldelt a (Lamarche 1987).Breedin g in 1ver ylarg e colony inth eBai ed'Argui n (12940pair si n1984-85 )fro mApril-Septembe r (Campredon 1987).Flamingo swer e relatively rarei nth eBai ed'Aouati f in the 1986season .I nothe rpart so fth eBan cd'Arguin ,fo rinstanc enea r Arel,larg enumber swer erecorded .Th eoccurrenc e ofsmal lnumber s inth e Baied'Aouati f thereforewil lhav ebee na loca lphenomenon .Altenbur ge t al. (1982)counte d 60,000-80,000Greate rFlamingo sa tth eBan cd'Argui n during the 1980expedition . 10/3/851 4imm .an d 1ad .L aCherka ,Nouadhibo u 11/3/854 6L aCherka ,Nouadhibou ,amon gwhic h 1colour-ringe d (probably thesam ebir da so n5/5/85) . 15/3/853 1(al limm. )S par tPresqu'îl ed eCa pBlan c 24/3/8548 0Bai ed'Aouati f 4/4/85 42Ebel kAiznai ,1 colour-ringe d (probably thesam ebir da so n 15/4/85). 12/4/85abou t 50sit e 1,1 5other sflyin gove ri nN directio n 13/4/858 8Zira ;2 6leavin gN Wpar tBai ed'Aouati f inNN Wdirectio n(7.3 5 p.m.) 14/4/85 14leavin gN Wpar t Baied'Aouati f inNN Wdirectio n (7.40p.m. ) 15/4/853 9durin ghig h tideEbel kAiznai ,1 o fthes ecolour-ringed .Thi s birdwa sringe d inth eCamargu eo n2 7Jul y 1982an d resightedafterward s

122 inCadiz ,Spai no n3 1Octobe r 1982an d inS Franc e fromMa y 1986onward s (AlanJohnson ,i nlitt.) . 16/4/8584 3Bai ed'Aouati f 20-23/4/85u pt o 100foragin garoun dNai r 23/4/85+ +Niroum i 24/4/8549 1Bal ed'Aouati f 27/4/857 3Ebel kAizna i 1/5/85 1700i nN Epar t He d'Arguin 3/5/85 66Presqu'îl e deCa pBlan c 5/5/85 ++L aCherka ,Nouadhibo uon eo f thesecolour-ringe d asa pullu s inth eCamargu ei n 1984(Ala nJohnsso n inlitt. ) 7/5/85 167Ebel kAizna i 8-20/2/861 3Bai ed'Aouati f 11/2/8625 0counte d fromplan ebetwee nIoui kan d He d'Arguin 14-21/2/86 5-7Zir a 22/2/86 1Ebel kAizna i 23/2/864 0Ebel kAiznai ,migratin gN ; 19Bai ed'Aouati f 24/2-17/3/86abou t 10N par tBai ed'Aouati f 13-14/3/86 6-7 Zira 18/3/863 Ebel kAizna i 21/2/8632 0S Wpar tSerin l 22/2/86+-H -betwee nTidr aan dAjoueïr ;10 0E Ajoueï r 23/3/86 100Bai ed'Aouatif ; 150S ti pTidr a 24/3/86man y thousandsbetwee n Iouikan dKij i 25/3/86-H -betwee nRgueïb aan dSerin i 27/3-3/4/86 3-19i nBai ed'Aouati f andaroun dZir a 4/4/86 200betwee nAre lan dNiroum i 5/4/86 26N Wpar tBai ed'Aouati f 6/4/86 40Tivid e 7/4/86 2000N WAre l 9/4/86 20N Wpar tTidr a 10/4/866 0Bai ed'Aouatif ,4 6migratin g N(5.0 0p.m. ) 11/4/86 11Ebel kAiznai ;1 5Bai ed'Aouatif ;++ +Are l 12/4/863 8N Wpar tBai ed'Aouati f 13/4/86 200Niroumi ;50 0W par to fTidr a 14/4/865 0Bai ed'Aouati f 16/4/86 11Ebel kAiznai ;4 7Bai ed'Aouatif ; 11Ioui kmigratin gN 17-18/4/8639-4 7N Wpar tBai ed'Aouati f

~~~~123 22-23/4/86 56-63N Wpar t Baied'Aouati f 24-25/4/86++ +surrounding s of Iled'Argui n~~~~

Phoenicopterusmino r LesserFlaming o PetitFlaman t Arar emigran t fromAfro-tropica lregions ,generall y onlyrecorde d So f Tidra (Lamarche 1987). 31/3/852 ad .Bai ed'Aouati f 1/4/85 1ad .Bai ed'Aouati f

Anasacut a Pintail Canardpile t Varyingnumber swinte r inth eSénéga ldelta ,number srangin g from 1000u p to40,000 .Migratin galon g thecoas t fromOctober-Decembe ran d January-March (Lamarche 1987).Altenbur g etal .(1982 )observe d upt o2 5 Pintails insevera lplace sa t theBan cd'Argui ndurin g the198 0 expedition. 22/3/856 Bai ed'Aouati f 25/3/856 flyin gN ove rIoui k 17/2/86 13male san d 2female sN par tBai ed'Aouati f 18/2/862 2flyin g Snea rcam p 25/2/869 male san d 4female sflyin gN WN par tBai ed'Aouati f

~~~~Table 10.3Weigh t (g)an dbiometrica ldat a (mm)o fa femal ePintai l captured ina mistne t inth eBai ed'Aouatif ,sit e1~~~~

~~~~date weight wing tarsus~~~~

~~~~26/3/85 660 248 38.5~~~~

Anascrecc a Teal Sarcelled'hive r Winteringi nsmal lnumber si nth eSénéga ldelta .Migratio nalon gth e coasti nOctober-Novembe r andFebruary-Marc h (Lamarche 1987).Altenbur g etal .(1982 )foun d 1dea dTea la tTidr adurin g the 1980expedition .

~~~~124 Table 10.4 Weight (g)an dbiometrica ldat a (mm)o fa mal eTea lcapture d ina mistne ti nth eW par to fth eBai ed'Aouatif . date weight wing~~~~

~~~~17/3/86 395 189~~~~

Anasquerquedul a Garganey Sarcelled'ét é Wintering inlarg enumber s inth eSénéga ldelt a (onaverag e 100,000). Migrationalon g thecoas tnote d fromSeptember-Novembe r and inFebruar y andMarc h (Lamarche 1987).Altenbur g etal .(1982 )observe d upt o2 3 Gargeneysi nsevera lplace sa tth eBan cd'Argui n during the198 0 expedition. 24/3/853 male san d 3female sBai ed'Aouatif ,flyin gS W 13/3/86 14flyin gS Wnea rcam p

Anasclypeat a Shoveler Canard souchet Wintering inrathe rsmal lnumber si nth eSénéga ldelt aan dinlan d wetlands inS Mauritania .Migratio nnote d fromOctober-Decembe r andi n Januaryan dFebruar y (Lamarche 1987).Altenbur ge tal .(1982 )observe du p to6 0Shoveler s insevera lplace sa tth eBan cd'Argui n during the198 0 expedition. 22/3/852 male san d 6female sflyin gN Eove rcam p 24/3/85 1mal eN o fIoui k 26/3/852 6(abou t 50%males ,50 %females )leavin g theBai ed'Aouati f inN direction 13/4/852 female sBai ed'Aouatif ,sit e2 25/2/86 2male san d 2female sN par tBai ed'Aouati f 7/4/86 corpseo ffemal efoun dTidr a

Milvusmigran s Black.Kit e Milannoi r Two subspeciesma yb eobserve d inMauritania .M.m .migran sprobabl yi s theonl ysubspecie s theexpeditio nencountered ,M.m .parasiticus ,a n Afro-tropicalsubspecies ,ha s itsN rang earoun d the 17thdegre eo f latitude."Migrans "i sa nrathe rcommo nmigran t inAugus tan d September andFebruar yan dMarc h (Lamarche 1987).Altenbur g etal .(1982 )observe d 16Blac kKite sa t theBan cd'Argui n on7 Marc h1980 .

125 1/4/85 1nea rcam p 2/4/85 1nea rcamp ,exhausted ,missin g 1leg ,i nactiv ewin gmoul t 4/4/85 1nea rcam p 6/4/85 1Bai ed'Aouati fsit e6 ,differen t from theon eo n2/4/8 5 8-12/4/851 nea rcam p 28/4/858 o ndea d camel,rubbis h tipCa pBlan c 5/5/85 6L aCherka ,Nouadhibo u 21/3/862 5circlin g overcam p 22/3/86u pt o70 ,presen tal love ri nth esurrounding s ofIoui k 23/3/86 1circlin gove rcam p 30-31/3/86 1circlin g overcam p 2/4/86 8ove rcam pi nN directio n

Neophronpercnopteru s Egyptianvultur e Percnoptère d'Egypte Smallnumber sar e recorded throughout theyear .Ca nb erecorde do n migration,a sa winterin ggues ta swel la sa breedin g bird,mos to fthes e inth eE par to fth ecountr y (Lamarche 1987). 28/4/85 10o nrubbis h tipCa pBlan c

Gypsfulvu s GriffonVultur e Vautourfauv e Smallnumber sar e recorded onpassag ei ncoasta l regionso f thecountry , mosto f thesei nautum n (Lamarche 1987). 14/3/85 1o nrubbis h tipL aCherka ,Nouadhibo u mnil5/3/853 o nbeac hN Nouadhibo u 11/4/85 1Ioui k 25/1/862 circlin gove rL aCherka ,Nouadhibo ui nN directio n

Circusaeruginosu s MarshHarrie r Busardde sroseau x Numerouso npassag ea swel la sa winterin gguest ,especiall y incoasta l regions.Recorde d onmigratio nfro mAugust-Octobe r andFebruary-Ma y (Lamarche 1987).Altenbur g etal .(1982 )counte d 62Mars hHarrier sa tth e Bancd'Argui n during the 1980expedition . 15/3/851 mal eL aCherka ,Nouadhibou ; 1mal ealon gbeac hN Nouadhibo u 24/3/85 1Bai ed'Aouatif ,disturbin ghig h tideroost s 25/3/85 1E par t Baied'Aouati f 27/3/85 1nea rcam p 29/3/85 1nea r Iouik; 1Bai ed'Aouatif ,sit e3 30/3/85 1ad.mal eTivide ;1 mal ean d 1femal eEbel kAiznai ;1 femal ecam p

126 31/3/85 1Ioui kflyin gS ; 1ad .mal eEbel kAizna i 2/4/85 1W par t Baied'Aouatif ; 1femal eNair ;1 ad .mai eEbel kAizna i 3-4/4/851 femal eEbel kAizna i 5/4/85 1ad .mai eIouik ;2 Ebel kAizna i 6/4/85 8Ebel kAizna i 7-14/4/851- 2Ebel kAizna i 9/4/85 1mai ean d 1femal eEbel kAiznai ;1 mal enea rcamp ; 1femal e flyingN ove rcam p 12-21/4/85 1W par tBai ed'Aouati f 25/4/85 1femal eEbel kAizna i 8-22/2/861 Ebel kAizna i 8/2-18/3/861- 2W par tBai ed'Aouati f 20/2/863 Ebel kAizna i 21/2/86 1femal eE coas tTidr a 24/2/86 1Serin i 20-22/3/86 3-6W par tBai ed'Aouati f 23-24/3/86 1-3Bai ed'Aouatif ,sit e3 24/3/863 betwee n Iouikan dKij i 25/3/86 1Ajoueï r 25/3/-11/4/86frequentl y 1-2Bai ed'Aouati f 9/4/861 N Wpar tBai ed'Aouati f 20/4/86 1Tivid e 25/4/86 1Il ed'Argui n

Circuscyaneu s HenHarrie r Busard Saint-Martin Occasionalvisito r toMauritania ,mos t frequently observed inSeptember , Octoberan dMarc h (Lamarche 1987). 15/3/861 ad .mal eBai ed'Aouatif ,sit e1 21/3/86 1ad .mal eW par tBai ed'Aouati f 22/23/3/86 1imm .mal eW par tBai ed'Aouati f 24/3/86 1femal eNai r 31/3/86 1femal eBai ed'Aouatif ,sit e1

Circuspygargu s Montagu'sHarrie r Busard cendré Rather smallnumber sar erecorde d asa winterin g guest inth eS par to f thecountr ya swel la sdurin gmigration ,especiall y inSeptembe ran di n March-April (Lamarche 1987). 4/4/85 1mal enea rcam p

127 5/4/85 1femal ean d 3male sEbel kAlznai ; 1mal ean d 1femal eIoui k 6/4/85 2male san d 2female sBal ed'Aouatif ,sit e6 7/4/85 1femal e nearcam p 8/4/85 2female snea rcam p 9/4/85 1femal ean d 2male sEbel kAizna l 11/4/85 1mal eIoul k 13/4/85 1mal enea rcam p 12/4/862 male san d 1femal eEbel kAizna i

Pandionhaliaetu s Osprey Balbuzard pêcheur Locallya rathe rcommo nwinte rvisito ran dmigrant ,predominantl yalon g thecoast .Migratin g individualsmos t frequentlyobserve dfro m October-December and inMarch-Apri l (Lamarche 1987).Altenbur g etal . (1982)counte d 92Osprey sa t theBan cd'Argui ndurin g the198 0 expedition. 13/3/85 1Ca pBlan c 14-15/3/85 1L aCherka ,Nouadhibo u 23/3-18/4/85 1-2W par tBai ed'Aouati f 7/4/85 1Ebel kAizna i 13/4/851 Zir a 28/4/85 1fishin gCa pBlan c 3/2/86 1L aCherka ,Nouadhibo u 5/2/86 2 Kiaone 7-12/2/86 3W par tBai ed'Aouati f 13/2-12/3/86 1-2W par tBai ed'Aouati f 17-18/2/86 1Zir a 21/2/86 1S Fou mA lTriqu e 22/2/86 1S Epar tTidr a 23/2/86 1Ajoueïr ;1 S ti pTidr a 25/2/863 E par tBai ed'Aouati f 2/3/86 1L aCherka ,Nouadhibo u 13/3/86 1 Zira 14/3/863 W par tBai ed'Aouati f 16/3-3/4/86 1-2W par tBai ed'Aouati f 18/3/86 1N Wpar tBai ed'Aouatif ; 1Ebel kAizna i 23/3/863 W par tBai ed'Aouati f 24/3/86 2Niroumi ;1 Kij i 1-2/4/861 Zir a

~~~~128 4/4/86 1N o fNai r 5-6/4/861- 2N Wpar tBai ed'Aouati f 7/4/86 1Are l 20/4/862 betwee nTivid ean dSerin i 21/4/86 1N Wpar t Baied'Aouati f~~~~

Falcotinnunculu s Kestrel Fauconcrécerell e Twosubspecie sar efoun d inMauritania ,onl yth enominat eoccurin g inth e Wpar to f thecountry .Commo nwinte rvisito r toth eS par t ofth e country.O nmigratio nmos t frequently foundalon g thecoas ti n October-Novemberan dMarch-Ma y (Lamarche 1987). 13/3/852 corpse sfoun dCa pBlan c 18/3/85 1i ngarde nNouadhibo u 1/4/85 1corps e foundNai r 2/4/85 1Bai ed'Aouatif ,sit e5 3/4/85 1flyin gN ove rcamp ;1 Ioui k 4/4/85 1nea rcamp ;2 i nth edeser tbetwee nEbel kAizna ian dcam p 5/4/85 1mal eEbel kAiznai ;1 femal ecam pcatchin ga Phylloscopu s 6/4/85 4W par tBai ed'Aouati f 7-9/4/851 nea rcam p 11/4/85 1Ioui k 4/5/85 1cit ycentr eNouadhibo u 19/1-2/2-86 1femal eSaba hhotel ,Nouadhibo u 19/3/86 1femal eBai ed'Aouatif ,sit e 1,showin gactiv ewin gmoul t 21/3/86 1mal enea rcam p 22/3/864 Bai ed'Aouatif ,sit e 1;1 cam p 23/3/865-1 0W par tBai ed'Aouati f 24/3/865 Bai ed'Aouatif ,sit e 1;5 Niroumi ; 10Kij i 25/3/86 3betwee nRgueïb aan dZira ;1 Bai ed'Aouatif ,sit e 1;1 cam p 27/2/86 1betwee nTeïcho tan dRgueïb a 31/3/867 W par tBai ed'Aouati f 1/4/86 1Bai ed'Aouatif ,sit e 1;5 Nouadhibo u 2-4/4/861- 2cam p 5/4/86 1N N Wpar tBai ed'Aouati f 16/6/86 1 camp 26/4/86 1L aCherka ,Nouadhibo u 27/4/86 1Cansad o

~~~~129 Table 10.5Weigh t (g)an dblometrica ldat a (mm)o fKestrel s captured in mistnetsnea r thecam p date weight wing bill age~~~~

~~~~6/4/85 182 230 15.6 2nd c.y. 6/4/85 177 247 15.6 2nd c.y. 8/4/85 139 248 14.4 ad.~~~~

Falcobiarmicu s Lanner Fauconlanie r Thesubspecie sF.b .erlanger i isfoun da sa breedin gbir d inth eNW ,W and Spar to fth ecountr y (Browne tal . 1982)bu t isequall y observeda s awinte rvisito ra swel la sdurin gmigration ,especiall yfro m August-October andi nApril-Ma y (Lamarche 1987).Altenbur g etal .(1982 ) counted 15Lanner sa t theBan cd'Argui ndurin g the 1980expedition . 11/3/85 1chasin gLittl eGul lL aCherka ,Nouadhibo u 12/3/85 1eatin ga ter nL aCherka ,Nouadhibo u 13/3/852 o nth ebeac hN Nouadhibo u 15/3/85 1rubbis hti pL aCherka ,Nouadhibou , 1N Nouadhibo uAirpor t 21/3/85pai rIouik ,femal ecatchin ga Dunli n 23/3/85 1nea rcamp ,catchin ga Ringe dPlove r 24/3/85 1N Epar tBai ed'Aouati f 27/3/85 1nea rcam p 3/4/85 1i nth edeser tbetwee nEbel kAizna ian dcam p 6/4/85 1Ebel kAizna i 14/4/85 11 0k mN EIoui k 17/4/851 W par tBai ed'Aouati f 20/4/85 1nea rBiologica l StationIoui k 22/4/85 1hil lN o fEbel kAizna i 25/4/85pai rBai ed'Aouatif ,sit e3 ,on eo fthes eeatin gsmal lwade r 26/4/852 flyin gove rmudflat sopposit ecam p 30/4/85 1cam p 1/5/85 2li ed'Argui n 5/5/85 1L aCherka ,Nouadhibo u 22/1/86 1L aCherka ,Nouadhibou ,carryin ga wade ra spre y 3/2/86 1L aCherka ,Nouadhibo u 6/2-19/4/861- 2frequentl y observed Wpar tBai ed'Aouatif ,sometime s

130 displaying. 8/2/86 1nea rairstri pBai ed'Aouatif ,chasin ga Redshan k intoth e water; 1Ebel kAizna icatchin ga Ringe dPlove r 11/2/86 1chasin gwaders ,givin g specialnotic e toa Redshan k 22-24/2/86 1Ebel kAiznai .I ti suncertai nwhethe r thisbir dwa son eo f thetw ofrequentl y observed inth eBai ed'Aouati f 18/3/86 1Ebel kAizna i 20/3/862 mangrove sW o fTidr a 24/3/86pai reatin ga Knot ,Bai ed'Aouatif ,sit e1 11/4/86 1mal eW par t Baied'Aouatif ,eatin ga Kno t 12/4/86 1Ebel kAizna i 20/4/863 Tivid e 24/4/86 1Kiaon e

Fulicaatr a Coot Foulquemacroul e Irregularwinte rvisito r toMauritania ,th epresenc eo fwhic hquit eofte n isonl ynote d through thefindin g ofcorpse s (Lamarche 1987). 15/3/85 1dea d bird found inlagoo nN airpor tNouadhibo u

Coturnixcoturni x CommonQuai l Caillede sblé s Rather smallnumber sar epresen t inMauritani aa sa winte rvistor .Smal l numbersar esee ndurin gmigration ,mainl yalon g thecoast ,fro m September-November and inFebruary-Marc h (Lamarche 1987). 16/2/86 1femal ecapture dnea r thecamp ;weigh t 112g 27/4/86 1corpse ,dea d forsevera lmonths ,Biologica l StationIoui k

~~~~Porphyrioporphyri o PurpleCoo t Poulesultan e Thesubspecie s"madagascariensis "i sfoun d throughout theyea ri nth eS part ofth ecountr y thoughnumber sar ehighl yvariabl e (Lamarche 1987).~~~~

~~~~Table 10.6 Biometricaldat a (mm)o f2 corpse so fPurpl eCoot sfoun da t theN par to fTidra ,bot h"madagascariensis" ,dea d forapprox .2- 3month s~~~~

~~~~date wing bill tarsus age~~~~

~~~~14/4/86 240 37.2 85.2 3rdc. y 14/4/86 246 36.6 88.2 2ndc. y~~~~

131 Haematopusostralegu s Oystercatcher Huitrierpi e Numberscounte d inwinte ra tth eBan cd'Argui nvar yfro m600 0(Trotigno n et al. 1980)t o920 0(Altenbur g etal . 1982). Somethousand swinte r furtherS i nSénègambi aan dGuine aBissa u (Smit& Piersm ai nprep.) .Fo r furtherdetail s seeAppendi x1 . 11/3/853 1L aCherka ,Nouadhibo u 15/3/859 4S par tPresqu'îl ed eCa pBlan c 24/3/85 1065Bai ed'Aouati f 3/4/85 116Ebel kAizna i 13-14/4/855- 8Ioui k 15/4/85 123Ebel kAizna i 16-24/4/8534-4 5Ebel kAizna i 17/4/8527 5Bai ed'Aouati f 21/4/854 (al lwit hcollars )o nhig htid eroos tNai r 22/4/85 130Bai ed'Aouati f 23/4/85 1Niroum i 25/4/8539 3Bai ed'Aouati f 27/4/85 75Ebel kAiznai ;3 1betwee n Iouikan dEbel kAizna i 3/5/85 33S par tPresqu'îl ed eCa pBlan c 10/5/85 11L aCherka ,Nouadhibo u 3/2/86 30L aCherka ,Nouadhibo u 7/5/85 109Ebel kAizna i 8/2/86 300Bai ed'Aouatif ; 220Ebel kAizna i 13-22/2/86210-28 7Ebel kAizna i 12-19/3/86 140-250Bai ed'Aouatif ,site s 1an d3 20/3/8631 0N Wpar tBai ed'Aouati f 29/3/8637 3N Wpar tBai ed'Aouatif ,a tleas t 156o fthes eleavin gi nN direction 11/4/86 1Are l 14/4/86onl y 13stil lpresen t inN Wpar t Baied'Aouati f 20/4/863 0betwee nTivid ean d Serini,1 1o fthes e2n dc.y .bird s 24/4/864 migratin gN li ed'Argui n

Himantopushimantopu s Black-winged Stilt Echasseblanch e Wintering insmal lnumber s inS Mauritani a (Lamarche 1987).Som e thousandshav ebee ncounte da sa winte rvisito r inSénègambi a(Smi t& Piersmai nprep.) . Passage inMauritani a isnote despeciall yi n September-October andMarch-April ,alon g thecoas ta swel la sinlan d

132 (Lamarche 1987).Altenbur g etal .(1982 )di dno tobserv e thespecie sa t theBan cd'Argui ndurin g the 1980expedition . 7/4/85 35Ebel kAizna i 25/2/861 i nmangrove sN Timiri s 30/3/864 0N Wpar tBai ed'Aouati f

Recurvirostraavosett a Avocet Avocette Somehundred sar ewinterin g inth eS par t ofMauritani a (Lamarche 1987), somethousand swinte r furtherS i nSènêgambl aan dGuine aBissa u (Smit& Piersmai nprep.) . Passage inMauritani a isnote d fromAugust-Octobe ran d inMarch ,especiall yalon g thecoas t (Lamarche 1987).Altenbur g etal . (1982)di dno tobserv eth especie sa tth eBan cd'Argui n during the198 0 expedition.Fo rfurthe rdetail s seeAppendi x1 . 13/3/85+ roostin gN par tBai ed'Aouati f 28-29/3/859 Bai ed'Aouatif ,sit e3 30/3/854 2roostin g Baied'Aouatif ,sit e3 31/3/854 Bai ed'Aouatif ,sit e5 14/4/85 15departin g fromN par tBai ed'Aouati f 17/4/854 N par tBai ed'Aouati f 18/4/854 o nhig h tideroos tEbel kAizna i 14/3/864 Bai ed'Aouatif ,sit e1 28/3/86 11Bai ed'Aouatif ,sit e1 29/3/8628 7departin g fromN par tBai ed'Aouatif ,2 colour-ringe d 4/4/86 7N o fNiroum i 8/4/86 86N Wpar tBai ed'Aouati f 11-18/4/86 13N Wpar tBai ed'Aouati f 16/4/866 2N par tBai ed'Aouati f 21/4/866 5N Wpar tBai ed'Aouatif ,non eo f thesebein gcolour-ringe d 22/4/863 4N Wpar tBai ed'Aouatif ,6 leavin gi nN direction ; 28Ebel k Aiznai

Burhinusoedicnemu s StoneCurle w Oedicnèmecriar d Mainly seeni nsmal lflock s (someindividuals )o nmigration ,inlan da s wella salon g thecoast ,fro mSeptember-Decembe r and fromJanuary-Marc h (Lamarche 1987). 11-12/3/8538-4 5L aCherka ,Nouadhibo u 15/3/852 0L aCherka ,Nouadhibo u 22/1/86 10L aCherka ,Nouadhibo u

~~~~133 31/1/86 12L aCherka ,Nouadhibo u 3/2/86 5L aCherka ,Nouadhibo u 3/3/86 25L aCherka ,Nouadhibo u 25/3/86som ecall shear dRgueïb a 26/4/86cal lhear d overNouadhibo u~~~~

Cursoriuscurso r Cream-coloured Courser Courviteisabell e Presenta sa breedin gbir dan da sa winte rvisito r throughoutth e country.See no nmigratio n fromAugust-Decembe r andMarch-Apri l (Lamarche 1987). 13/3/852 Ca pBlan c January 1986Som ehundred s rubbish tipCa pBlan c (comm.Pierr eCampredon ) 22/1/86 1flyin gove rSaba hhotel ,Nouadhibou ;2 rubbis hti pL aCherka , Nouadhibou

Glareolapratincol a Pratincole Glarèoleà collie r Commonwinte rvisito r inth eS par to fth ecountry .Autum n (September-November)an d spring (March-April)migratio n ismainl ynote d inth einterio rpar t ofth ecountr y (Lamarche 1987). 5/4/85 1Bai ed'Aouatif ,sit e6

Charadriusdubiu s LittleRinge dPlove r PetitGravelo t Winteringalon gwetland si nS Mauritania .Smal lnumber sar esee no n migration,mainl y inAugust-Septembe ran dMarch-Jun e(Lamarch e 1987). Altenburge tal .(1982 )observe d 1Littl eRinge dPlove ra tth eBan c d'Arguinan d 1i nNouadhibo udurin g the 1980expedition . 12/3/85 15L aCherka ,Nouadhibo uan dnearb yrubbis hti p 15/3/855 S par tPresqu'îl ed eCa pBlan c 22/3/86 1nea rcamp ;1 N Wpar tBai ed'Aouati f migratingN (7.00p.m. ) 23/3/86 1Bai ed'Aouatif ,sit e1 29/3/86 1Bai ed'Aouatif ,sit e 1;1 nea rcam p 3/5/85 10S par tPresqu'îl e deCa pBlan c 10/5/852 L aCherka ,Nouadhibo u

Charadriushiaticul a Ringed Plover GrandGravelo t Numberscounte d inwinte ra tth eBan cd'Argui nvar yfro m98,00 0 (Altenburg etal .1982 )t o 136.500(Trotigno ne tal .1980) .A smuc ha s 57,000ar ebelieve d towinte r inGuine aBissa u (Zwarts 1988), 5000-15,000

134 areestimate d towinte ro nth eMauritania ncoas tan d inth eSénéga l delta.Passag ei nMauritani a ismainl ynote d inAugust-Octobe ran d March-June (Lamarche 1987).Fo rfurthe rdetail sse eAppendi x1 . 14/3/8530 0L aCherka ,Nouadhibo uan d onnearb yrubbis hti p 15/5/8537 1S par tPresqu'îl ed eCa pBlan c 24/3/85452 2Bai ed'Aouati f 3-16/4/85264-34 4Ebel kAizna i 17/4/85355 5Bai ed'Aouati f 20-22/4/85abou t 100S par tNiroum i 24/4/85 180Ebel kAizna i 25/4/85292 8Bai ed'Aouati f 27/4/8540 0Ebel kAizna i 3/5/85 110S par tPresqu'îl ed eCa pBlan c 7/5/85 330Ebel kAizna i 10/5/857 5L aCherka ,Nouadhibo u 22/1-3/2/86-H-+ -L aCherka ,Nouadhibo u 8-22/2/86485-70 0Ebel kAizna i

Charadriusalexandrinu s KentishPlove r Gravelotà collie rinterromp u Numberscounte d inwinte ra tth eBan cd'Argui n varyfro m 6500(Trotigno n etal . 1980)t o18,00 0(Altenbur g etal .1982) .Som e20,00 0winte r furtherS i nSénêgambi aan dGuine aBissa u (Smit& Piersm ai nprep.) . Breedingalon g thecoas t fromth eBan cd'Argui n toS Mauritania .Passag e noted fromSeptember-Octobe ran dMarch-Apri l (Lamarche 1987).Fo rfurthe r detailsse eAppendi x1 . 15/3/85 113S par tPresqu'îl ed eCa pBlan c 24/3/85 1383Bai ed'Aouati f 3-16/4/85264-34 4Ebel kAizna i 17/4/8585 0Bai e d'Aouatif 21/4/852 Nai r 24/4/856 0Ebel kAizna i 25/4/8545 6Bai ed'Aouati f 27/4/855 Ebel kAizna i 3/5/8512 8S par tPresqu'îl ed eCa pBlan c 7/5/8510 2Ebel kAizna i 10/5/851 7L aCherka ,Nouadhibo u 22/1/8650-10 0L aCherka ,Nouadhibo u 13-22/2/8621-3 0Ebel kAizna i

135 Pluvialissquatarol a GreyPlove r Pluvierargent é Numberscounte d inwinte ra tth eBan cd'Argui nvar yfro m 14,200 (Trotignone tal . 1980)t o24,00 0(Altenbur g etal . 1982). Some60,00 0 winterfurthe rS i nSènêgambi aan dGuine aBissa u (Smit& Piersm ai n prep.), 1500-2000ar eestimate d towinte ralon g theMauritania ncoast . Passagenote d fromAugust-Novembe ran dMarch-Ma y (Lamarche 1987).Fo r furtherdetail s seeAppendi x1 . 10-11/3/85 1-3L aCherka ,Nouadhibo u 13/3/853 Ca pBlan c 15/3/85 180S par tPresqu'îl ed eCa pBlan c 24/3/85 1253Bai ed'Aouati f 3/4/85 127Ebel kAizna i 16/4/8540 0Ebel kAizna i 17/4/85 1921Bai ed'Aouati f 20-22/4/8580 0a thig htid eroos tNai r 22/4/8564 6Ebel kAizna i 24/4/8538 5Ebel kAizna i 25/4/85 1702Bai ed'Aouati f 27/4/8523 2Ebel kAizna i 3/5/85 114Ebel kAizna i 7/5/85 321Ebel kAizna i 10/5/858 L aCherka ,Nouadhibo u 22/1/8650-10 0L aCherka ,Nouadhibo u 3/2/86 200L aCherka ,Nouadhibo u 8/2/86 267Ebel kAizna i 13/2/8664 2Ebel kAizna i 22/2/86 115Ebel kAizna i 24/4/86 15migratin gN He d'Arguin 26/4/86+ L aCherka ,Nouadhibo u

Calidriscanutu s Knot Bécasseaumaubèch e Numberscounte d inwinte ra tth eBan cd'Argui nvar yfro m334,00 0 (Trotignone tal . 1980)t o367,00 0(Altenbur g etal . 1982).Larg enumber s (144,000)winte r furtherS i nGuine aBissa u (Zwarts 1988). InMauritani a passage isnote d fromSeptember-Octobe r andMarch-Apri l (Lamarche 1987). Forfurthe rdetail s seeAppendi x1 . 11/3/8520 0L aCherka ,Nouadhibo u 136 H/3/85 70L aCherka ,Nouadhibo u 15/3/8529 2S par tPresqu'îl ed eCa pBlan c 24/3/854551 3Bai ed'Aouati f 3-16/4/858383-908 0Ebel kAizna i 17/4/854075 4Bai ed'Aouati f 20-22/4/85++-H -Nai r 22/4/85632 6Ebel kAizna i 25/4/85 19028Bai ed'Aouati f 27/4/85350 0Ebel kAizna i 1/5/85 10000N Epar tIl ed'Arguin ; 17.2510 0leavin g inN directio n 3/5/85 251S par tPresqu'îl ed eCa pBlan c 7/5/85 3191Ebel kAizna i 10/5/85 142L aCherka ,Nouadhibo u 22/1/8650-10 0L aCherka ,Nouadhibo u 3/2/86 50L aCherka ,Nouadhibo u 8-22/2/862750-560 0Ebel kAizna i 26/4/86+ L aCherka ,Nouadhibo u

Calidrisalb a Sanderling Bécasseausanderlin g Numberscounte d inwinte ra tth eBan cd'Argui n varyfro m 6600(Trotigno n etal . 1980)t o34,00 0(Altenbur ge tal . 1982),700 0ar eestimate dt o wintero nth eMauritania ncoas titsel f (Lamarche 1987).Man y thousands areknow nt owinte r furtherS alon g theW Africa ncoast ,eve nS t oth e Rep. SAfric a (Smit& Piersm ai nprep.) .Passag ei nMauritani a isnote d fromSeptember-Novembe r andi nMarch-Apri l (Lamarche 1987).Fo rfurthe r detailsse eAppendi x1 . 11-12/3/85+ L aCherka ,Nouadhibo uan dnearb y rubbishti p 13/3/85 100Ca pBlan c 15/3/85205 9S par tPresqu'îl ed eCa pBlan c 24/3/8547 9Bai ed'Aouati f 3/4/85 50Ebel kAizna i 16/4/85 104Ebel kAizna i 17/3/8552 0Bai ed'Aouati f 20-22/4/85max .2 0Nai r 22/4/8549 5Ebel kAizna i 25/4/8593 8Bai ed'Aouati f 27/4/8532 2Bai ed'Aouati f 3/5/85 1257S par tPresqu'îl ed eCa pBlan c

137 7/5/85 160Ebel kAizna i 10/5/8521 5L aCherka ,Nouadhibo u 22/1-3/2/86 200-300 La Cherka, Nouadhibou 8-22/2/86189-28 9Ebel kAizna i 20/4/8620-3 0betwee nSerin ian dTivid e 26/4/86+ +L aCherka ,Nouadhibo u

Calidrisminut a Little Stint Bécasseauminut e Numberscounte d inwinte ra tth eBan cd'Argui nvar yfro m 1000(Trotigno n etal . 1980)t o44,00 0(Altenbur g etal . 1982).A smuc ha s 123,000ar e knownt owinte r inGuine aBissa ualon e (Zwarts 1988),man y thousandsar e knownt owinte relsewher e inW Afric a (Smit& Piersm ai nprep.) .Passag e inMauritani a isnote d inSeptember-Novembe r andi nMarch-Apri l (Lamarche 1987).Fo rfurthe r details seeAppendi x1 . 12-13/3/85 1-2L aCherka ,Nouadhibo uan dnearb yrubbis hti p 15/3/852 5S par tPresqu'îl ed eCa pBlan c 24/3/85312 2Bai ed'Aouati f 3/4/85 60Ebel kAizna i 16-27/4/85315-37 5Ebel kAizna i 17/4/85505 2Bai e d'Aouatif 20-22/4/85+ Nai r 22/4/85 700Ebel kAizna i 25/4/85434 5Bai ed'Aouati f 3/5/85 32S par tPresqu'îl ed eCa pBlan c 5/5/85 atleas t 10L aCherka ,Nouadhibo u 7/5/85 140Ebel kAizna i 10/5/855 L aCherka ,Nouadhibo u 13/2/8630 0Ebel kAizna i 22/2/86 164Ebel kAizna i 26/4/86+ L aCherka ,Nouadhibo u

Calidrisferrugine a CurlewSandpipe r Bécasseaucocorl i Numberscounte d inwinte ra tth eBan cd'Argui n varyfro m 129,000 (Trotignone tal . 1980)t o 174,000(Altenbur g etal .1982) .Approximatel y 250,000ar eknow n towinte r inGuine aBissa u (Zwarts 1988).Approximatel y 20,000ar eestimate d towinte ro nth eMauritania ncoast ,mos to fthes ei n theS par to fth ecountry .Passag e inMauritani a isnote di n September-November andi nMarch-Apri l (Lamarche 1987).Fo rfurthe r

138 detailsse eAppendi x1 . 14/3/85 1rubbis hti pnea rL aCherka ,Nouadhibo u 15/3/852 S par tPresqu'îl ed eCa pBlan c 24/3/85441 2Bai e d'Aouatif 3/4/85 195Ebel kAizna i 16/4/85321 0Ebel kAizna i 17/4/85 13633Bai ed'Aouati f 20-22/4/85a tleas t 80o nhig h tideroos tNai r 22-27/4/85608-70 0Ebel kAizna i 25/4/85516 4Bai ed'Aouati f 3/5/85 1S par tPresqu'îl ed eCa pBlan c 7/5/85 1082Ebel kAizna i 3/2/86 3L aCherka ,Nouadhibo u 8-22/2/86440-52 0Ebel kAizna i

~~~~Calidrismaritim a PurpleSandpipe r Bécasseauviole t A stragglert oMauritania ,no tinclude d inth elis tb yLamarch e1987 . 5/4/85 1Ebel kAizna i~~~~

Calidrisalpin a Dunlin Bécasseauvariabl e Numberscounte d inwinte ra tth eBan cd'Argui nvar yfro m705,00 0 (Trotignone tal . 1980)t o818,00 0(Altenbur g etal . 1982).Som e thousandswinte rfurthe r Si nSénégambi aan dGuine aBissa u (Smit& Piersmai nprep.) .U pt o30,00 0ar eestimate d towinte r inS Mauritani a and theSénéga ldelta .Passag ei nMauritani a isnote d inOctober-Novembe r andMarch-Apri l (Lamarche 1987).Fo rfurthe rdetail s seeAppendi x1 . 11/3/85 100L aCherka ,Nouadhibo u 15/3/8566 1S par tPresqu'îl ed eCa pBlan c 24/3/85 56,085Bai ed'Aouati f 3/4/85 3220Ebel kAizna i 16-27/4/852200-256 0Ebel kAizna i 17/4/8522,16 3Bai ed'Aouati f 20-22/4/85++ +o nhig h tideroos tNai r 25/4/8531,84 5Bai ed'Aouati f 1/5/85 25leavin g He d'Arguin inN directio n (5.25 p.m.); 380(5.3 0 p.m.) 3/5/85 128S par tPresqu'îl ed eCa pBlan c 7/5/85 1437Ebel kAizna i 139 10/5/85 12L aCherka ,Nouadhibo u 22/1/8650-10 0L aCherka ,Nouadhibo u 8/2/86 4025Ebel kAizna i 12/2/86 1albin oBai ed'Aouati f 13/2/86 1950Ebel kAizna i 22/2/86460 0Ebel kAizna i 18/4/86 1albin oNiroum i 26/4/86+ +L aCherka ,Nouadhibo u

Limicolafalcinellu s Broad-billed Sandpiper Bécasseaufalcinell e Astraggle r toMauritania ,no tinclude d inth elis tb yLamarch e1987 . 22/3/85 1W par tBai ed'Aouatif ,winte rplumag emoultin g towardssumme r plumage 25-26/4/85 1Bai ed'Aouatif ,sit e1

Philomachuspugna x Ruff Chevallier combattant Known towinte r inlarg enumber s infreshwate rwetland si nW Afric a(Smi t & Piersma inprep.) « Commonwinte rvisito r toMauritania ,especiall yi n theS par to fth ecountry .Passag ei snote d inSeptember-Novembe r andi n February-April (Lamarche 1987).Altenbur ge tal .(1982 )observe du pt o1 5 Ruffa tth eBan cd'Argui n during the 1980expedition . 1/3/85 1femal eo nrubbis h tipnea rL aCherka ,Nouadhibo u 15/3/851 S par tPresqu'îl ed eCa pBlan c 24/2/863 migratin gN i nN Wpar tBai ed'Aouati f

Limosalimos a Black-tailed Godwit Bargeà queu enoir e Wintering inlarg enumber si nfreshwate rwetland san dricefield si nW Africa.Approximatel y 110,000-120,000ar eknow nt owinte ri nGuine a Bissau (Altenburg &va nde rKam p 1985). Passagei nMauritani a isnote di n September-November andi nMarch-Apri l (Lamarche 1987).Altenbur g etal . (1982)observe d upt o2 5Black-taile d Godwitsa t theBan cd'Argui ndurin g the 1980expedition . 12-15/3/85 1L aCherka ,Nouadhibo u 3/3/86 1L aCherka ,Nouadhibo u 23/3/865 0N Wpar tBai ed'Aouatif ,leavin g intw oflock si nN directio n

~~~~Limosalapponic a Bar-tailed Godwit Bargerouss e Numberscounte d inwinte ra t theBan cd'Argui n vary from538,00 0~~~~

140 (Trotignone tal .1980 )t o543,00 0(Altenbur g etal .1982) . Over 150,000 areknow nt owinte ri nGuine aBissa u (Zwarts 1988),30,000-40,00 0ar e estimated towinte r onth eMauritania n coast itself.Passag ei n Mauritania isnote d inSeptember-Octobe r andMarch-Apri l (Lamarche 1987). Forfurthe rdetail s seeAppendi x1 . 14/3/85 100L aCherka ,Nouadhibo u 15/3/8547 5S par tPresqu'îl ed eCa pBlan c 24/3/85 18,518Bai ed'Aouati f 3-16/4/852275-250 7Ebel kAizna i 17/4/85 14,578Bai ed'Aouati f 20-22/4/85 12,000a thig htid eroos tNai r 22-24/4/85 1410-1525Ebel kAizna i 25/4/85 13,312Bai ed'Aouati f 27/4/8582 2Ebel kAizna i 3/5/85 222S par tPresqu'îl ed eCa pBlan c 7/5/85 760Ebel kAizna i 10/5/858 3L aCherka ,Nouadhibo u 22/1/8650-10 0L aCherka ,Nouadhibo u 3/2/86 100L aCherka ,Nouadhibo u 8/2/86 4100Ebel kAizna i 13/2/86219 0Ebel kAizna i 24/4/86 100Zir amigratin g inN directio n (12.45a.m. ) 26/4/86+ +L aCherka ,Nouadhibo u

Numeniusphaeopu s Whimbrel Courliscorlie u Numberscounte d inwinte ra tth eBan cd'Argui nvar yfro m 10,500 (Trotignone tal . 1980)t o15,60 0(Altenbur g etal .1982) .Ove r 40,000 winter furtherS i nGuine aBissa u (Zwarts 1988),2000-600 0ar e thoughtt o wintero nth eMauritania ncoas t itself.Passag ei nMauritani a isnote di n September-October andMarch-Apri l (Lamarche 1987).Fo rfurthe rdetail s seeAppendi x1 . 10/3/85+ L aCherka ,Nouadhibo u 15/3/856 1S par tPresqu'îl ed eCa pBlan c 24/3/8524 5Bai ed'Aouati f 16/4/8527 1Ebel kAizna i 17/4/8547 6Bai ed'Aouati f 20-22/4/85 1500o nhig h tideroos tNai r 22/4/8521 0Ebel kAizna i

141 23/4/85+-H -i nmangrov eare a Spar tNiroum i 24/4/853 4Ebel kAizna i 25/4/8524 4Bai ed'Aouati f 27/4/85 190Ebel kAizna i 3/5/85 53S par tPresqu'îl e deCa pBlan c 7/5/85 129Ebel kAizna i 10/5/858 L aCherka ,Nouadhibo u 22/1/865-1 0L aCherka ,Nouadhibo u 3/2/86 10L aCherka ,Nouadhibo u 8/2/86 110Bai ed'Aouatif ;40 0Ebel kAizna i 13/2/868 Ebel kAizna i 22/2/8651 1Ebel kAizna i 24/4/862 2S Il ed'Arguin ,migratin gN (7.0 0p.m. ) 26/4/86+ +L aCherka ,Nouadhibo u

Numeniusarquat a Curlew Courliscendr é Numberscounte d inwinte ra tth eBan cd'Argui nvar yfro m 10,500 (Trotignone tal . 1980)t o 14,200(Altenbur g etal .1982) . Several thousandswinte r furtherS i nSènégambi aan dGuine aBissa u (Smit& Piersmai nprep.) , 1500-3000ar eestimate d towinte ro nth eMauritania n coastitself .Passag ei nMauritani a isnote d inSeptember-Novembe r andi n February-May (Lamarche 1987). 11/3/857 L aCherka ,Nouadhibo u 12/3/852 0L aCherka ,Nouadhibo u 15/3/85 17S par tPresqu'îl ed eCa pBlan c 17/3/855 2Bai ed'Aouati f 24/3/8532 0Bai ed'Aouati f 3-15/4/85 1-8Ebel kAizna i 18/4/851 o nhig htid eroos tEbel kAizna i 21/4/85 1o nhig h tideroos tNai r 22/4/853 Ebel kAizna i 23/4/85-H -S par tNiroum i 3/5/85 6S par tPresqu'îl ed eCa pBlan c 4-10/5/85 1-3L aCherka ,Nouadhibo u 21/1-3/2/86 10-11L aCherka ,Nouadhibo u 8-22/2/86 42-80Ebel kAizna i 11/4/863 Ioui kmigratin gN (7.3 0p.m. ) 21/4/862 migratin gE Bai ed'Aouati f

142 Tringaerythropu s SpottedRedshan k Chevalierarlequi n Wintering throughoutW Africa ,mainl y infreshwate rwetlands .Smal l numbersar ewinterin g inMauritania ,especiall y inth eS par t ofth e country.Passag e isnote d inSeptember-Octobe r andFebruary-Marc h (Lamarche 1987).Altenbur g etal .(1982 )di dno tobserv eth especie sa t theBan cd'Argui n during the 1980expedition . 21/3/85 1L aCherka ,Nouadhibo u 30/3/85 1Bai ed'Aouatif ,sit e3 7/4/85 1nea rcam p 12/4/851 Bai ed'Aouatif ,sit e1 20/4/85 1Bai ed'Aouatif ,sit e1 21/4/85 1alon g thecoas tN o fIoui k 11/3/86 1Bai ed'Aouatif ,sit e5 17/3/86 1nea rcam p 22/3/86 1Bai ed'Aouatif ,sit e1 25/3/865 Bai ed'Aouatif ,sit e5 30/3/863 nea rcam p 31/3/862 nea rcamp ;1 N Wpar t Baied'Aouati f 1/4/86 1Bai ed'Aouatif ,sit e 1;2 L aCherka ,Nouadhibo u 4/4/86 1Bai ed'Aouatif ,sit e1

Tringatotanu s Redshank Chevaliergambett e Numberscounte d inwinte ra tth eBan cd'Argui n varyfro m31,00 0 (Trotignone tal . 1980)t o70,00 0(Altenbur ge tal . 1982).Ove r 80,000 areknow nt owinte r inGuine aBissa u (Zwarts 1988).A variabl enumbe ri s wintering inS Mauritania ,especiall y inth eSénéga ldelt a (Lamarche 1987).Passag ei nMauritani a isnote d inSeptember-Octobe r andi n March-April (Lamarche 1987).Fo rfurthe rdetail s seeAppendi x 1. 10-14/3/85 1-3L aCherka ,Nouadhibo u 15/3/856 1S par tPresqu'îl ed eCa pBlan c 24/3/85297 8Bai ed'Aouati f 3-16/4/85191-20 0Ebel kAizna i 17/4/8596 5Bai ed'Aouati f 20-22/4/85-H -o nhig h tideroos tNai r 22/4/85 14Ebel kAizna i 23/4/85++ +i nmangrove s Spar tNiroum i 25/4/8569 9Bai ed'Aouati f 27/4/856 8Ebel kAizna i

143 3/5/85 33S par tPresqu'îl e deCa pBlan c 7/5/85 55Ebel kAizna l 3/2/86 2L aCherka ,Nouadhibo u 8/2/86 490Ebel kAizna i 13-22/2/86 41-67Ebel kAizna i 29/3/8627 8N Wpar t Baied'Aouati fmigratin gN 26/4/86+ L aCherka ,Nouadhibo u

Tringa stagnatilis MarshSandpipe r Chevalier stagnatile Smallnumber sar erecorde d inwinte ra swel la so no npassage ,mainl yi n August-September andMarch-April .Singl e individualsar eknow nt owinte r onth eBan cd'Argui n (Lamarche 1987). 2/4/861 N par t Baied'Aouati f

Tringanebulari a Greenshank Chevalieraboyeu r Numberscounte d inwinte ra tth eBan cd'Argui n varyfro m85 0(Trotigno n etal . 1980)t o 1500(Altenbur g etal . 1982). Somethousand swinte r furtherS i nSènégambi aan dGuine aBissa u (Smit& Piersm ai nprep.) ,som e hundredshav ebee nfoun d towinte r inS Mauritania .Smal lnumber so f migrating individualsar erecorde d inAugust-Novembe r andMarch-Ma y (Lamarche 1987). 12-14/3/85 15-20L aCherka ,Nouadhibo u 15/3/852 2S par tPresqu'îl ed eCa pBlan c 24/3/855 4Bai ed'Aouati f 3/4/85 10Ebel kAizna i 9/4/85 75Ebel kAizna i 17/4/8514 8Bai ed'Aouati f 18/4/85floc k (sizeunknown )leavin gBai ed'Aouati f 23/4/85+ +i nmangrov eare aS par tNiroum i 25/4/8523 7Bai ed'Aouati f 27/4/856 0Ebel kAizna i 7/5/85 181Ebel kAizna i 22/1/865-1 0L aCherka ,Nouadhibo u 3/2/86 10L aCherka ,Nouadhibo u 8-13/2/867-1 3Ebel kAizna i 22/2/86 1Ebel kAizna i 3-15/4/865 0W par tBai ed'Aouati f 26/4/86 18L aCherka ,Nouadhibo u

~~~~144 Table 10.7.Weigh t (g)an dbiometrica ldat a (mm)o fa Greenshan kcapture d ina mistne tW par tBai ed'Aouati f date weight wing bill tarsus+toe age~~~~

~~~~6/3/86 163 198 49.4 99 >2nd c.y.~~~~

Tringaochropu s GreenSandpipe r Chevalier cul-blanc Acommo nwinterin g guest inS Mauritania ,mainl y inth eW par to fth e country,bu trar eo nth eBan cd'Arguin .Passag ei snote di n August-October and inFebruary-Apri l (Lamarche 1987). 20/3/86 1W par tBai ed'Aouati f 15/4/861 nea rcam p

Tringaglareol a Wood Sandpiper Chevalier sylvain Smallnumber sar ewinterin g inMauritania ,mor e frequently observed duringmigration .Mai npassag ei snote d inAugust-Septembe ran d March-April (Lamarche 1987).Altenbur ge tal .(1982 )di dno tobserv eth e speciesa tth eBan cd'Argui n during the198 0expedition . 15/3/852 lagoo nN o fairpor tNouadhibo u 3/4/85 1tida lflat sopposit ecam p 5/4/85 1nea rcam p

Actitishypoleuco s CommonSandpipe r Chevalierguignett e Smallnumber sar ewinterin g inMauritania ,mor efrequentl yobserve d duringmigration .Mai npassag ei snote d inAugust-Septembe ran di n February-April (Lamarche 1987).Altenbur ge tal .(1982 )observe d 5-10 CommonSandpiper s inL aCherka ,Nouadhibo ui nJanuar yan dMarc h 1980an d 5a tKiaon edurin g the 1980expedition . 10/3/852 L aCherka ,Nouadhibou ; 1Cansad o 15/3/85 10S par tPresqu'îl ed eCa pBlan c 30/3/85 1Ioui k 5/4/85 1nea rcam p 6/4/85 1nea rcamp ;1 Ebel kAizna i 7-14/4/851 Ebel kAizna i 23/4/855 S par tNiroum i 25/4/85 17Bai ed'Aouati f

145 3/5/85 8S par tPresqu'îl ed eCa pBlan c 7/5/85 3Ebel kAizna i 22/1-3/2/86 1L aCherka ,Nouadhibo u 4/2/86 1ne wharbou rNouadhibo u 16/2/86 1nea rcam p 3/3/86 25-30L aCherka ,Nouadhibo u 31/3/86 1nea rcamp ; 1N Wpar tBai ed'Aouatif ; 1N par tBai ed'Aouati f migratingN 1/4/86 2Bai ed'Aouatif ; 1L aCherka ,Nouadhibo u 2/4/86 10Zir a 13/4/863 mangrove s Tidra;1 Niroum i 16/4/86 1Kiaon e 16-21/4/86 1nea rcam p 19/4/86 1N Wpar tBai ed'Aouati f 26/4/865-1 0L aCherka ,Nouadhibo u

Arenaria interpres Turnstone Tournepierre Numberscounte d inwinte ra t theBan cd'Argui nvar yfro m600 0(Trotigno n etal . 1980)t o 17,000(Altenbur g etal . 1982).Approximatel y 5000ar e estimated towinte rbetwee nChott'Bou lan dCa pTimiris t (Lamarche 1987). Many thousandswinte r inSénégambi aan dGuine aBissa u(Smi t& Piersm ai n prep.). Passage inMauritani a isnote d fromSeptember-Novembe r andi n March-April (Lamarche 1987).Fo rfurthe rdetail sse eAppendi x1 . 10/3/853 0Cansad o 11/3/8525 0L aCherka ,Nouadhibo u 15/3/8522 1S par tPresqu'îl ed eCa pBlan c 24/3/8564 0Bai ed'Aouati f 3/4/85 24Ebel kAizna i 16/4/85 193Ebel kAizna i 17/4/85 1016Bai ed'Aouati f 20-22/4/85 1500a thig h tideroos tNai r 22/4-3/5/85 158-201Ebel kAizna i 25/4/8575 8Bai e d'Aouatif 7/5/85 63Ebel kAizna i 10/5/855 0L aCherka ,Nouadhibo u 22/1/8650-10 0L aCherka ,Nouadhibo u 12/2/86 148Ebel kAizna i 13-22/2/8657-6 9Ebel kAizna i

~~~~146 11/3/86500-60 0roostin g Iouik,probabl ycomin g fromtida lflat sW Ioui k 15/3/86a tleas t40 0roostin gIoui k 17/3/8674 0Ioui k 26/4/86-H -L aCherka ,Nouadhibo u~~~~

Stercorariusparasiticu s ArcticSku a Labbeparasit e Smallnumber sar ewinterin g inMauritania ncoasta lwaters ,generall y 50-70ar ewinterin ga tth eBan cd'Arguin .Presen t fromSeptember-Apri l (Lamarche 1987). 13/3/85 10-15Ca pBlan c

Stercorarius skua Great Skua GrandLabb e Smallnumber sar ewinterin g inMauritania ncoasta lwaters ,abou t 50ar e winteringa tth eBan cd'Arguin .Presen t fromSeptember-Marc h (Lamarche 1987).Altenbur g etal .(1982 )observe d 1Grea tSku ai nth eBai ed e Lévrierdurin g the198 0expedition . 5/2/86 20-30Bai ed eLévrie r

Larusminutu s LittleGul l Mouettepygmé e Frequently observeda tth eBan cd'Argui n fromNovember-March ,thoug h always insmal lnumber s (Lamarche 1987).Altenbur g etal .(1982 )observe d onejuvenil eLittl eGul li nNouadhibo udurin gth e 1980expedition . 11/3/851 juv .L aCherka ,Nouadhibo u 25/3/85 1Ioui k 5/5/85 2secon d c.y. and 1thir dc.y .L aCherka ,Nouadhibo u

Larusmelonocephalu s MediterraneanGul l Mouettemélanocéphal e Smallnumbers ,mainl y immature individuals,ar ewinterin g inMauritania n coastalwaters .Presen tfro mSeptember-Apri l (Lamarche 1987).Altenbur g etal .(1982 )observe du pt o5 Mediterranea nGull si nNouadhibo udurin g the 1980expedition . 22/1/86 1imm .L aCherka ,Nouadhibo u 18/3/862 thir d c.y.an d 1secon d c.y.N Wpar tBai ed'Aouati f 1/4/86 3L aCherka ,Nouadhibo u 9/4/86 2imm .N Wpar tBai ed'Aouati f

~~~~Larus ridibundus Black-headed Gull Mouetterieus e About400-50 0ar ewinterin ga tth eBan cd'Arguin ,anothe r 300-400ar e~~~~

147 wintering inth eSénéga ldelta .Presen t fromSeptember-Ma y (Lamarche 1987).Altenbur ge tal .(1982 )counte d 115Black-heade d Gullsa tth eBan c d'Arguindurin g the 1980expedition .Fo rfurthe rdetail s seechapte r 9.4.1. 11/3/85++ +L aCherka ,Nouadhibo u 15/3/85 120S par tPresqu'îl e deCa pBlan c 24/3/856 Bai ed'Aouati f 25/3/85 1Ioui k 26/3/854 ad .an d 2imm .Ioui k 29/3/85 10Ebel kAizna i 31/3/85 10Iouik , 1o f these incomplet ewinte rplumag e 3/4/85 +Ioui k 12-22/4/85 1-6Ioui k 25/4/85 1ad .Bai ed'Aouati f 10/5/85 15L aCherka ,Nouadhibo u 3/2/86 ++L aCherka ,Nouadhibo u 8/2/86 2Ebel kAizna i February 1986:frequen t observationso fu pt o5 Black-heade d Gullsa t severalplace si nth eBai ed'Aouatif ,mos to fthes earoun d Iouikan d Zira.Number sdroppin g inth ecours eo fApril . 18/2/866 ad .an d 8imm .leavin g theBai ed'Aouati f 22/2/867 Ebel kAizna i 2/3/86 200L aCherka ,Nouadhibo u 15/3/867 betwee ncam pan dsit e1 17/3/862 8ad .an d 5imm .N Wpar tBai ed'Aouati f 18/3/86 12ad. ,1 secon dc.y .an d 1thir d c.y.N Wpar tBai ed'Aouati f 24/3/865-1 0betwee nIoui kan dKij i 25/3/865-1 0betwee nRgueïb aan dZir a 26/3/866 ad .an d 3imm .restin gBai ed'Aouatif ,sit e1 29/3/864 N Wpar tBai ed'Aouati f 3/4/86 4ad . and 9imm . betweenBai ed'Aouatif ,sit e 1an d Iouik;2 Gibene 7/4/86 atleas t 1ad .an d 1imm .Ioui k 8/4/86 13N Wpar tBai ed'Aouatif ,3 o fthes ei nsumme rplumage ,2 i n half completed,2 i n1/ 4complete d summerplumage ,6 i nwinte rplumag e 9/4/86 2Tivid e 12/4/862 N Tidr a 20/4/862 migratin gN i nN Wpar tBai ed'Aouati f

~~~~148 26/4/864 L aCherka ,Nouadhibo u~~~~

Laruscirrocephalu s Grey-headed Gull Goélandà têt egris e Present throughout theyear ,winterin ga swel la sbreedin g inMauritania . Rarely found inland (Lamarche 1987).Altenbur g etal .(1982 )counte d8 1 Grey-headed Gullsa tth eBan cd'Argui n during the 1980expedition . Breedinga tth eBan cd'Argui n in2 smal lcolonie sa tZir aan dKiaon e(1 5 pairsi n1984-85 )fro mMay-Jul y (Campredon 1987).Surprisingl yfe w sightings fromNouadhibo uan dsurroundings .Fo rfurthe rdetail sse e chapter 9.4.2. 21/3/854 Te nAllou l 22/3/85 21alon g thewater' sedg enea r thecam pt oS 24/3/852 2Bai ed'Aouati f 26-30/3/85 10Ioui k 31/3/854 Ebel kAiznai ;1 Ioui k 8-9/4/852 Ebel kAizna i 9/4/85 6Ioui k 17/4/858 2Bai ed'Aouati f 22/4/85 1Ebel kAizna i 25/4/852 6Bai ed'Aouati f 1986: Numbersappea r toincreas eslightl y inth ecours eo fFebruary . 7/2/86 2ad .an d 1imm .Ebel kAizna i 8/2/86 1Ebel kAizna i 9-14/2/861- 5aroun d Ziraan dIoui k 15/2/86 10Ioui k 22/2/868 Ebel kAiznai ;2 nea rcam p 24/2-3/3/86 5-10Ioui k 3/3/86 1ad .L aCherka ,Nouadhibo u 10-13/3/86 10-20Ioui k 18/3/86 1Ebel kAizna i 22/3/86 1ad .an d 1imm .i nwin gmoul tnea r thecam p 24/3/865-1 0betwee nNai ran dRgueïb a 25/3/865-1 0betwee nRgueïb aan dSerin i 1-3/4/86abou t 20Ioui k 7/4/86 ++Are l 13/4/865 Niroumi ;1 Tidr a

149 Larusgene i Slender-billed Gull Goéland railleur Presenta sa winterin g guest,a sa breedin g birdan da sa migrant . Occasionally foundinland .Passag ei snote d inOctobe ran dFebruary-Marc h (Lamarche 1987).Altenbur g etal .(1982 )counte d 2462Slender-bille d Gullsa tth eBan cd'Argui n during the 1980expedition .Breedin g atth e Bancd'Argui n in6 colonie s (1610pair si n 1984-85,101 0o fthes ea t Zira)fro mApril-Jul y (Campredon 1987).Fo rfurthe rdetail s seechapte r 9.4.4. 11/3/85 100L aCherka ,Nouadhibo u 15/3/8531 5S par tPresqu'îl ed eCa pBlan c 23/3/85 23ad .non e inful lsumme rplumage ,feedin g inth echanne lnea r thecam po nsmal lfis hb yplungin g for3. 5hrs . 24/3/85 713Bai ed'Aouati f 26/3-23/4/8520-10 0frequentl y observed inIoui kan dnea rth ecam p 13/4/85++ +Ebel kAiznai ,arrivin gfro mZir a 16/4-7/5/85 20-31Ebel kAizna i 17/4/85243 5Bai ed'Aouati f 18/4/85 135flyin gN nea rcam p 20-22/4/85onl ysmal lnumber sa tNai r 23/4/85smal lnumber severywher ebetwee nIoui kan dNiroum i 25/4/85 1666Bai ed'Aouatif , 150o fthes enea rcam p 27/4/8520 0Iouik ,remarkabl yman ya scompare d topreviou sday s 28/4/8520 0Iouik ,arrivin gfro mZira ,mainl ypresen tdurin glo wtid e 1/5/85 +++N Epar t ofH e d'Arguin;++ +betwee nIoui kan d He d'Arguin 2/5/85 +++Bai ed eLévrie r 3/5/85 60S par tPresqu'îl ed eCa pBlan c 10/5/86 13L aCherka ,Nouadhibo u 3/2/86 +L aCherka ,Nouadhibo u 1986: numbersaroun d Iouikincreasin g inth ecours eo fFebruar yan dMarc h 8/2/86 50Ebel kAizna i 13/2/862 0Ebel kAizna i 14/2/864 0aroun d Iouik 15/2/86 13nea rcamp ;5 0Ioui k 16/2/864 3feedin gsociall yN Wpar tBai ed'Aouati f 21/2/863 0Ioui k 22/2/862 9Ebel kAizna i 24-26/2/8640-6 0Ioui k 24/3/86+ +betwee nIoui kan dKij i 150 25/3/86+ +betwee nRgueïb aan dZir a 1/4/86 150Ioui k 9-14/4/8625-10 0frequentl y feeding sociallynea rcam p 26/4/86+ L aCherka ,Nouadhibo u

Larusaudouini i Audouin'sGul l Goélandd'Audoui n Smallnumber so findividua lbird san d someoccasiona l smallflock sar e foundalon g thecoas ta sa winterin g guest fromNovember-Ma y (Lamarche 1987). 20/3/85 1ad .Bai ed eLévrie r 3/2/86 2L aCherka ,Nouadhibo u 31/-1/43/865 ad .an d 10imm .L aCherka ,Nouadhibou ,on eo fthes e colour-ringed,possibl y inSpain .

Larusfuscu s LesserBlack-backe d Gull Goélandbru n Intheor yw ema yexpec tbot hL.f .fuscu san dL.f .graellsi i inMauritani a butals oLaru sargentatu smichahelli s (Urbane ta l 1986).Especiall yL.f . graellsiian dL.a .michahelli sar edifficul t todistinguis h inth efield . During the 1985an d 1986expedition sn oseriou sattempt swer emad et od o so.Fo rthi sreaso nal lobservation so fLesse rBlack-backe d Gull-like birdshav ebee nlumpe d toL .fuscus .Ou robservation s suggesta decreas e innumber si nth ecours eo fMarc han dApril .Fo rfurthe rdetail sse e chapter9.4.3 .Altenbur g etal .(1982 )counte d 7468"Lesse r Black-backed Gulls"a tth eBan cd'Argui n during the 1980expedition . 10/3/85++ +L aCherka ,Nouadhibo u 13/3/85++ +Ca pBlan c 15/3/85 120S par tPresqu'îl ed eCa pBlan c 24/3/852 ad .an d 23imm .Bai ed'Aouati f 26/3/853 0Ioui k 31/3/85 1ad .an d 6imm .Ioui k 8/4/85 30Ebel kAizna i 12/4/855 ad .an d 1Imm .Ioui k 13/4/85 1ad .an d 4imm .Ioui k 17/4/868 Bai ed'Aouati f 18/4/852 ad .an d 3imm .Ioui k 22/4/85 1imm .Ioui k 25/4/85 4Bai ed'Aouati f 27/4/85 1Ebel kAiznai ;1 imm .Ioui k

151 28/4/858 9Bai ed'Aouati f probablymigratin g inN Wdirectio n 2/5/85 ++betwee n Iouikan d lied'Argui n 3/5/85 685S par tPresqu'îl ed eCa pBlan c 10/5/85 130L aCherka ,Nouadhibo u 3/2/86 +++L aCherka ,Nouadhibo u 8/2/86 100Bai ed'Aouatif ;4 0Ebel kAizna i 13-22/2/86 130-220Ebel kAizna i 14-24/2/86 50Ioui k 24/3/86+ +betwee nNai ran dRgueïba ,possibl ymigratin gN 25/3/86+ +betwee nRgueïb aan dZira ,possibl ymigratin gN 1/4/86 10Iouik ;5-1 0Serin i 2/4/86 20-30Giben e 7/4/86 ++Are l 13/4/86 19betwee nNiroum ian dTinimorgawo i 14/4/862 8migratin gN N Wpar tBai ed'Aouati f 20/4/86 1imm .betwee nSerin ian dTivid e 24/4/86+ betwee nIoui kan d lied'Argui n 25/4/86-H -Bai ed eLévrie r 26/4/86+ +L aCherka ,Nouadhibo u

Gelochelidonnilotic a Gull-billed Tern Sternehanse l Presenta sa winterin g guest,a sa breedin gbir dan da sa migrant ,mainl y fromAugust-May .Rarel y foundinlan d (Lamarche 1987).Altenbur ge tal . (1982)counte d 110Gull-bille d Ternsa t theBan cd'Argui n during the198 0 expedition.Breedin g onth eBan cd'Argui n in8 colonie s (1180pair si n 1984-85,45 0o f thesea tZira) ,mainl yo nsand yislands ,fro mMay-Augus t (Campredon 1987).Count so fth eBai ed'Aouati f showa considerabl e increasei nth ecours eo fApril .Fo rfurthe rdetail s seechapte r 9.3.7. 10/3/85 1L aCherka ,Nouadhibo u 24/3/85 1E par tBai ed'Aouati f 27-30/3/85 2-3ad .i nsumme rplumag eBai ed'Aouati f 31/3/854 betwee ncamp ,Ioui kan dEbel kAizna i 1-10/4/85abou t 10alon gth ewhol eW shorelin eo fth eBai ed'Aouati f 9/4/85 1Ebel kAizna i 12/4/855 Bai ed'Aouatif ,sit e 1;+ Ioui k 13/4/85+ betwee ncamp ,Ioui kan dEbel kAizna i 14/4/85 10Ebel kAizna i 17/4/8510 7Bai ed'Aouati f

152 18/4/85roos t of 10durin ghig h tideBai ed'Aouatif ,sit e1 20-22/4/854 0Nair ,frequentl ydisplayin g 22/4/854 Ebel kAiznai ;9 Bai ed'Aouatif ,sit e 1feedin g onFiddle rCrab s 23/4/85smal lnumber severywher ebetwee n Iouikan dNiroum i 25/4/85 191Bai ed'Aouati f 1/5/85 ++N Epar t lied'Arguin ;+ betwee n Iouikan d lied'Argui n 7/5/85 21Ebel kAizna i 10/5/85 1L aCherka ,Nouadhibo u 6/2-1/4/86abou t 10alon g thewhol eW shorelineo fBai ed'Aouati f 8/2/86 10Tivid e 18-22/2/86 2-3Ebel kAizna i 7/4/86 17Are l 8/4/86 8N Wpar tBai ed'Aouatif ; 5N EAre l 9/4/86 20N WTidra ; 10N Wpar tBai ed'Aouati f 11/4/864 Ebel kAiznai ;5 Arel ;5 Bai ed'Aouatif ,sit e 1;5 nea rcam p 12/4/861 2Ebel kAizna i 13/4/86+ +betwee nTidr aan dNiroumi ;+ surrounding s ofNai r 20/4/8620-3 0betwee nSerin ian dTivid e 21-22/4/86 15-20N Wpar tBai ed'Aouati f

Sternacaspi a CaspianTer n Sternecaspienn e Presenta sa winterin gguest ,a sa breedin gbir dan da sa migrant ,mainl y fromAugust-April .Abou t 1500-2000ar eestimate d towinte ra t theBan c d'Arguin,anothe r 400-500alon g theMauritania ncoast .Rarel yfoun d inland (Lamarche 1987).Altenbur ge tal .(1982 )counte d 2435Caspia n Ternsa tth eBan cd'Argui n during the 1980expedition .Breedin ga tth e Bancd'Argui n in5 colonie s (2575pair si n 1984-85,23 0o fthes ea tZira ) fromFebruary-Novembe r (Campredon 1987). Countsan doccasiona l observations showtha tpar to fth ebird sa tth eBan cd'Argui ni s resident,par ti sleavin g theare ai nth ecours eo fMarch-April .Fo r furtherdetail sse echapte r 9.3.2. 10/3/853 Cansad o 11/3/856 0L aCherka ,Nouadhibo u 13/3/85+ +Ca pBlan c 15/3/85 139S par tPresqu'îl ed eCa pBlan c 20/3/85+ +betwee nNouadhibo uan dTe nAllou l 22-30/3/85 1-2Ebel kAizna i 24/3/85 10Bai ed'Aouati f 153 25/3/85 1ad .an d 1fullgrow nchick ,beggin g forprey ,Bai ed'Aouati f 6/4/85 10Bai ed'Aouatif ,sit e6 7/4/85 20Ca pTafari t 15/4/854 0o nhig h tideroos tEbel kAizna i 17/4/855 Bai ed'Aouati f 20/4/853 Nai r 23/4/85 1Niroum i 25/4/8523 4Bai ed'Aouati f 1/5/85 ++betwee nIoui kan d He d'Arguin;+ H e d'Arguin 2/5/85 ++betwee nBai ed eLévrie r 3/5/85 64S par tPresqu'îl ed eCa pBlan c 7/5/85 6Ebel kAizna i 10/5/85L aCherka ,Nouadhibo u 3/2/86 100L aCherka ,Nouadhibo u 8/2/86 67Ebel kAizna i 9/2/86 500o nhig htid eroos tEbel kAiznai ;-H -surrounding s ofZir a 12/2-21/3/86abou t 10alon gW shorelin eBai ed'Aouati f 13/2/86 245Ebel kAizna i 22/2/86 100Ebel kAizna i 25/2/86 15Tivid e 26/2/862 N Wpar tBai ed'Aouatif ,eatin gfishe so f 15-20c m 28/2/86a tleas t 100Zir a 2-3/3/86150-20 0L aCherka ,Nouadhibo u 24/3/86+ +betwee nIoui kan dRgueïb a 25/3/86+ +betwee nRgueïb aan dZir a 16/4/8625 0pair sKiaon e 20/4/865 betwee nSerin ian dTivid e 24/4/86+ +betwee n Iouikan d lied'Argui n 25/4/86+ +Bai ed eLévrie r 26/4/86+ L aCherka ,Nouadhibo u

Sternamaxim a RoyalTer n Sterneroyal e Presenta sa winterin gguest ,a sa breedin gbir dan da sa migrant ,thoug h numbers inwinte rar elowe r thani nothe r seasons.Passage ,mainl yalon g thecoast ,i snote d inSeptember-Octobe r andMarch-Apri l (Lamarche 1987). Altenburg etal .(1982 )counte d 3339Roya lTern sa t theBan cd'Argui n during the 1980expedition .Breedin g onth eBan cd'Argui n in4 colonie s (5630pair si n 1984-85,33 0o f thesea tZira )fro mApril-Jul y (Campredon

154 1987).Fo rfurthe rdetail sse echapte r 9.3.3. 12/3/857 L aCherka ,Nouadhibo u 13/3/85 15Ca pBlan c 15/3/852 4S par tPresqu'îl ed eCa pBlan c 16/3/851 0Ioui k 20/3/85+ +betwee nNouadhibo uan dTe nAllou l 24/3/8536 0Bai ed'Aouati f 29/3/852 0Ioui k 30/3/85 100ad .Ebel kAiznai ,al ldisplayin g 7/4/85 300Ca pTafari t 16/4/8520 4Ebel kAizna i 17/4/8573 4Bai ed'Aouati f 21/4/852 Nai r 22/4/852 8Ebel kAiznai ;+ +Ioui k 25/4/8525 8Bai ed'Aouati f 27/4-7/5/85 32-40 Ebelk Aiznai 1/5/85 ++betwee n Iouikan d Iled'Arguin ;+ N Epar tli ed'Argui n 2/5/85 -H-Bai ed eLévrie r 3/5/85 28S par tPresqu'îl ed eCa pBlan c 5/5/85 1L aCherka ,Nouadhibo u 10/5/852 3L aCherka ,Nouadhibo u 8-22/2/8610-3 0Ebel kAizna i 14/2/86 1Zir a 24/2/86 1Serin i 3/3/86 1L aCherka ,Nouadhibo u 24/3/86+ +betwee n Iouikan dRgueïb a 25/3/86-H -betwee nRgueïb aan dZir a 2/4/86 ++Zira ;1 0L aCherka ,Nouadhibo u 7/4/86 +++Are l 24/4/86+ +Bai ed eLévrier ,mor enumerou s thanCaspia nTer n 25/4/86+ +betwee n Iled'Argui nan dNouadhibo u 26/4/86 1imm .L aCherka ,Nouadhibo u

Sternasandvicensi s SandwichTer n Sternecauge k Winteringa tth eBan cd'Argui n inlarg enumber s (29,000)a swel la salon g thecoas t (5000).Migratio nobserve d fromAugust-Octobe r andi n March-April (Lamarche 1987).Altenbur g etal .(1982 )counte d 250Sandwic h Ternsa tth eBan cd'Argui n during the 1980expedition .Number sobviousl y 155 decreasei nth ecours e ofMarch-April .Fo rfurthe rdetail s seechapte r 9.3.4. 10/3/85 1Cansad o 12/3/852 0L aCherka ,Nouadhibo u 13/3/8544-H -Ca pBlan c 15/3/85 101S par tPresqu'îl ed eCa pBlan c 30/3/85 10imm .an d 20ad .Ebel kAizna i 9/4/85 15Ebel kAizna i 14/4/854 Ebel kAizna i 15/4/852 9o nhig h tideroos tEbel kAizna i 16/4/866 Ebel kAizna i 17/4/858 Bai ed'Aouati f 18/4/85 10Iouik ,feedin g 25/4/85 1Bai ed'Aouati f 27/4/853 Ebel kAizna i 3/5/85 148S par tPresqu'îl ed eCa pBlan c 7/5/85 17Ebel kAizna i 10/5/85 16L aCherka ,Nouadhibo u 3/2/86 50L aCherka ,Nouadhibo u 8/2/86 265Ebel kAizna i 11-28/2/86+ +Bai ed'Aouati f 13-23/2/86200-26 0Ebel kAizna i 22/2/865 S Epar tTidr a 2/3/86 3L aCherka ,Nouadhibo u 1-15/3/86+ Bai ed'Aouati f 24/3/86+ +betwee n Iouikan dRgueïb a 25/3/86+ +betwee nRgueïb aan dZir a 31/3/862 N Wpar tBai ed'Aouati f 3/4/86 3Giben e 9/4/86 2N EArel ; 1betwee nAre lan dIoui k 13/4/86 10surrounding so fNiroum i 26/4/86 1L aCherka ,Nouadhibo u

Sternahirund o CommonTer n Sternepierregari n Presenta sa winterin g guest,a sa breedin g birdan da sa migrant ,mainl y fromSeptember-April ,inlan da swel la salon g thecoas t (Lamarche 1987). Altenburg etal .(1982 )observe d onlysmal lnumber sa tth eBan cd'Argui n during the 1980expedition .The ywer eno tabl et ovisi t theimportan t

156 roosta tCa pBlanc .Th especie si sbreedin ga t theBan cd'Argui ni n5 smallcolonie s (98pair si n 1984-85,5 0o fthes ea tZira )fro mMay-Jul y (Campredon 1987).Locall ynumerou sa searl ya sFebruar yan dMarc hbu ta t theBan cd'Argui n increasing innumber s inth ecours eo fMarch-April . Frequently seenmigratin gN i nMarch-April .Fo rfurthe rdetail sse e chapter 9.3.5. 11/3/85+ +L aCherka ,Nouadhibo u 13/3/85+++ +Ca pBlan c 15/3/85 10S par tPresqu'îl ed eCa pBlan c 17/3/85 1L aCherka ,Nouadhibo u 24/4/853 0Bai ed'Aouati f 30/3/853 0Ebel kAizna i 3/4/85 200Ebel kAiznai ,hal fo f these insumme rplumage ,som e displaying;2 Ioui k 15/4/854 0Ebel kAizna i 16/4/85 130Ebel kAizna i 18/4/852 0Ioui k 20/4/85+ +migratin g Nalon g thecam p 20-22/4/853 0Nair ,amon gwhic hdisplayin gcouple s 21/4/85 10ad .an d 10imm .Iouik ; 1imm .moultin g 9thprimar y 22/4/85 120Ebel kAiznai ;1 0ad .an d 15imm .Ioui k 27/4/856 Ebel kAiznai ;+ +Ioui k 1/5/85 ++betwee n Iouikan d He d'Arguin 2/5/85 ++betwee nH e d'Arguinan dNouadhibo u 3/5/85 425S par tPresqu'îl ed eCa pBlan c 7/5/85 70Ebel kAizna i 10/5/855 3L aCherka ,Nouadhibo u 8-13/2/861 Ebel kAizna i 16/2/86 1Bai ed'Aouati f 22/2/862 Ebel kAizna i 6-23/2/861 W par tBai ed'Aouati f 24/3/86 20Nair ;1 0Kij i 25/3/865-1 0betwee nRgueïb aan dZir a 28/3/86 10nea rcam p 29/3-22/4/86approx . 10-20W par tBai ed'Aouati f 1/4/86 30L aCherka ,Nouadhibo u 12/4/862 5Ebel kAizna i 13/4/862 0Nai r

~~~~157 16/4/868 Ebel kAizna i 17/4/865 E Are l 24/4/86+ +betwee n Iouikan d Iled'Argui n 25/4/86++ +Bai ed eLévrie r 26/4/862 0L aCherka ,Nouadhibo u~~~~

Sternaparadisae a ArcticTer n Sternearctiqu e Rathercommo nmigrant ,mainl y inSeptember-Octobe ran d in March-April, almost exclusivelyalon g thecoas t (Lamarche 1987).Altenbur g etal . (1982)observe d 5-10Arcti cTern si nNouadhibo udurin g the198 0 expedition.Probabl ymor enumerou sbu tno talway sdistinguishe d from CommonTerns .Fo rfurthe rdetail s seechapte r9.3.7 . 27/4/85 1Ioui k 25/3/862 Bai ed'Aouati f 12/4/86 15Ebel kAizna i

Sternaanaethetu s BridledTer n Sternebridé e Locallya commo nbreedin g bird,presen t inth ebreedin gcolonie sfro m April-October.Exclusivel y foundalon gth ecoast .N osighting so f wintering individuals (Lamarche 1987).Breedin ga tth eBan cd'Argui n in4 colonies (440pair si n1984-85 ,8 0o fthes ea tZira )fro mMay-July , apparently seriouslydeclinin g (Campredon 1987).Arrivin g inth ecours e ofApril . 19/4/85 15nea rZir a 22/4/85 15i npair sflyin gN nea rZir a 23/4/853 N EZir a 25/4/85 10nea rIouik ,comin gfro mZir a 4/4/86 3W Zir a 7/4/86 20aroun dAre l 9/4/86 5N o fTidra ; 1betwee nTidr aan dArel ;3 Are l

Sternaalbifron s LittleTer n Sternenain e About 300-400Littl eTern sar ewinterin ga t theBan cd'Arguin ,smal l numbersar efoun delsewher ealon g thecoast .Passag ei snote di n September-October and inApril-Ma y (Lamarche 1987).Altenbur g etal . (1982)counte d 371Littl eTern sa t theBan cd'Argui n during the198 0 expedition.Breedin g onth eBan cd'Argui n in4 smal lcolonie s (29pair s in 1984-85,5 o fthes ea tZira )fro mMay-Jul y (Campredon 1987).Onl yver y

158 smallnumber si nearl yFebruary ,gettin gmor enumerou sfro mmid-Februar y onwards.Fo rfurthe rdetail sse echapte r9.3.6 . 26/3/85 1Ioui k 27/3/853 nea rcam p 29/3/854 ove r thetida lflat sopposit ecam p 30/3/852 ad .Ebel kAiznai ;3 ad .nea rcam p 31/3/854 ad . Iouik;4 ad .nea rcam p 2/4/85 14Ebel kAizna i 3/4/85 50o nhig htid eroos tEbel kAiznai ;+ Iouik;2 nea rcam p 5-6/4/8552-5 3Bai ed'Aouatif ,sit e6 9/4/85 8Ebel kAizna i 14/4/85a tleas t2 2Ebel kAizna i 16/4-17/5/8539-5 2Ebel kAizna i 17/4/854 3Bai ed'Aouati f 20-22/4/85 6 Nair 22/4/85 10Ioui k 25/4/856 2Bai e d'Aouatif 27/4/85+ Ioui k 1/5/85 ++surrounding s ofIoui k 3/5/85 48Presqu'îl ed eCa pBlan c 10/5/857 L aCherka ,Nouadhibo u 7/2/86 atleas t2 Ebel kAizna i 8/2/86 2Ebel kAiznai ;1 betwee n Iouikan dEbel kAizna i 10-15/2/86+ W par tBai ed'Aouati f 13/2/862 Ebel kAizna i 15-28/2/86 10-20W par tBai ed'Aouati f 19/2/866 Ebel kAizna i 28/2/86 10Ioui k 1-30/3/8610-2 0W par tBai ed'Aouatif ,frequentl y 1-5nea rth ecam p 18/3/86 1Ebel kAizna i 24/3/86+ +betwee nIoui kan dKij i 25/3/86+ +betwee nRgueïb aan dZir a 1-24/4/86+ +Bai ed'Aouati f 3/4/86 20Giben e 7/4/86 +Are l 12/4/86 15Ebel kAizna i 13/4/86a t least 100Nai r 16/4/862 0Ebel kAizna i 159 25/4/86+ +Bai ed eLévrie r

Chlidoniasnigr a BlackTer n Guifettenoi r Present throughout theyear ,mainl yalon g thecoast .Migratin g birdsar e observed inSeptember-Octobe r and theen do fApril-Jul y (Lamarche 1987). Altenburg etal .(1982 )di dno tobserv e thespecie sa tth eBan cd'Argui n during the 1980expedition .Fo rfurthe rdetail s seechapte r 9.3.1. 11/3/85+ +L aCherka ,Nouadhibo u 15/3/85 10Presqu'îl ed eCa pBlan c 17/3/85 1L aCherka ,Nouadhibo u 12/4/853 0N o fTidr a 17/4/852 Bai ed'Aouatif ,bot ho fthes ei nEbel kAizna i 18/4/85 1Ebel kAiznai ;1 8migratin gN Iouik ; 1Ioui k 19/4/852 Iouik ;2 nea rcam p 21/4/85 1Ioui k 22/4/858 Ioui k 23/4/855 nea rcamp ;1 N EZir a 26/4/85 1nea rcam p 27-28/4/85 3Ioui k 1/5/85 1betwee nIoui kan d lied'Argui n 2/5/85 about 600Bai ed eLévrie r 3/5/85 44Presqu'îl ed eCa pBlan c 5/5/85 15L aCherka ,Nouadhibo u 7/5/85 31Ebel kAizna i 10/5/85 15L aCherka ,Nouadhibo u 7/4/86 25Are l 13/4/86 1N Tidra ;2 Zir a 23/4/863 nea rcam p 24/4/86+ betwee nIoui kan dIl ed'Argui n 25/4/86 100-200Bai ed eLévrier ,mos to f theseflyin g towardsnigh t roostsnea rNouadhibo u 26/4/865-1 0L aCherka ,Nouadhibo u

Chlidonias leucoptera White-winged BlackTer n Guifetteleucoptèr e Rathercommo ndurin gautum nan d springmigratio nbu ti nsom earea s infrequently observed.N oobservation s fromth eBan cd'Argui n (Lamarche 1987). 4-5/5/852 ad .an d 1imm .L aCherka ,Nouadhibo u

~~~~160 26/4/86 2ad .L aCherka ,Nouadhibo u~~~~

Streptopelia turtur TurtleDov e Tourterelle desboi s Twosubspecie soccu ri nMauritania ,th enominat ebein g theonl yon et ob e observed inth eW par t ofth ecountry .Te nthousand s ofS.t . turturar e wintering inth eS par to fth ecountry .Passag enote d inAugust-Octobe r and inApril-Ma y (Lamarche 1987). 5/4/85 2Nai r 8/4/85 1Ebel kAizna i 3/5/85 1nea r Sabahhotel ,Nouadhibou ,Nouadhibo u 4/5/85 2i ngarde nNouadhibo u 5/5/85 2nea rSaba hhotel ,Nouadhibou ,Nouadhibo u 2/3/86 1corps efoun dTanoudert ,win g 172mm . 22/3/86 1nea rcam p 27/3/86 1dea d birdbeache dnea rcam p 1/4/86 1garde nNouadhibo u 17/4/86 1Biologica lStatio n

Otusscop s ScopsOw l Hiboupeti tdu e Twosubspecie soccu ri nMauritania ,th enominat ebein g theonl yon e occurringa sfa rN a sNouadhibou .O.S .scop si sa winterin ggues ti n smallnumbers ,alon gth ecoas ta swel la sinland .Passag e isnote dmainl y fromSeptember-Decembe r and inApri lan dMa y (Lamarche 1987). 28/4/85 1corps e foundCa pBlan c

Asioflammeu s Short-eared Owl Hiboubrachyot e Rather smallnumber sar ewinterin galon g thecoas ta swel la si nth eS parto fMauritania .Passag e isnote d inOctober-Novembe r and inMarc h (Lamarche 1987).Altenbur g etal .(1982 )observe d 1individua lnea rTe n Alloulan d 3a tth eBan cd'Argui ndurin g the 1980expedition . 28-29/3/85 1alon g theshorelin enea r Iouik,flyin gu pwit hpre y 7/4/85 2Ca pTafari t

Apusapu s Swift Martinetnoi r Smallnumber sar efoun dwintering ,mainl y inth eS par to fth ecountry . Passagei snote d inAugust-Septembe ran dFebruary-Jun e (Lamarche 1987). Altenburg etal .(1982 )di dno tobserv e thespecie sa tth eBan c d'Arguin during the 1980expedition .

161 26-29/3/85 1-2 Iouikan dW par tBai ed'Aouati f 31/3/85 1nea rcamp ; 1(A .apus? )Ebel kAizna i 2-5/4/851- 2nea rcam pan dW par tBai ed'Aouatif ,som emigratin gN 6/4/85 2nea rcamp ;1 Bai ed'Aouatif ,sit e6 12/4/85 1Bai ed'Aouatif ,sit e1 18-20/4/85 2-3W par tBai ed'Aouati f 22/1/86 1ove rSaba hhotel ,Nouadhibo u 6/3/86 1N Wpar tBai e d'Aouatif 23/3/86 13nea rcam pbu tnumbe rchangin g throughout theday ;9 migratin g NEi nN Wpar tBai ed'Aouati f 24/3/8650-10 0migratin g Nbetwee nIoui kan dKiji ; 1nea rcam p 25/3/86 10-20betwee nRgueïb aan dZir a 3/4/86 2Giben e 8/4/86 2nea rcamp ,migratin gN 19/4/86 2nea rcamp ,migratin gN 21/4/863 nea rcam p 25/4/86 15nea r lied'Argui n overse a

Apus pallidus Pallid Swift Martinetpâl e Presenta sa breedin g birdan da sa migrant ,mainl y inSeptember-Octobe r and inFebruary-May .Breedin ga tCa pTafari tan da tKiaon ebu tsubspecie s ofth elatte rbird sobscur e (Lamarche 1987).Altenbur g etal .(1982 ) observedhundred si nIoui ko n3 Marc h 1980an donl ysmal lnumber s elsewherea t theBan cd'Argui ndurin g the 1980expedition . 3/4/85 1Ioui k 25/4/852 Bai ed'Aouatif ,sit e3

Apusnelb a AlpineSwif t Martinetalpi n Observed insmal lnumber sdurin gmigration ,mainl yi nSeptember-Octobe r andMarch-Jun e (Lamarche 1987). 23/3/86 13N Wpar tBai ed'Aouatif ,migratin gW a thig haltitud e

Apusaffini s HouseSwif t Martinet àcroupio nblan c Twosubspecie sar epresent .A.a .affinu si sa rathe rcommo nbreedin g bird,foun dal love r thecountr yan dbreedin gamon gother sa tKiaon ean d CapTafarit .A.a .galilejensi s isa migrant ,foun d insmal lflock salon g thecoas ta swel la sinland ,mainl y inSeptember-Octobe ran di n February-March (Lamarche 1987).Altenbur g etal .(1982 )observe dsom e

162 hundredsi nIoui ko n3 Marc h 1980an d someten selsewher ei nth esam e period during the 1980expedition . 24/3/85 1N par tBai ed'Aouati fflyin gN W 18/4/85 1Bai ed'Aouatif ,sit e3 flyin gN 28/2/86 1Ebel kAiznai ,flyin gN 23/3/86 1Bai ed'Aouatif ,sit e1 24/3/864 Bai ed'Aouatif ,sit e1

Meropsapiaste r Bee-eater Guêpier d'Europe Numerousa sa winterin g guesti nth eCasamanch e (Sénégal).Migratin g individualsar esee nfro mAugust-Decembe ran d inMarch-June ,thoug h springmigratio n israthe rinconspicuou s (Lamarche 1987). 29/3/85 1Ioui k 6/4/85 10Bai ed'Aouatif ,sit e5 ;8 sit e6 12/4/85cal lhear dwhe nunknow nnumbe rwa sflyin gove rcam p 18/4/858 Bai ed'Aouatif ,sit e3 23/3/864 1o nth esebka ,Bai ed'Aouatif ,sit e 1(10.4 5a.m.) ;2 0male s and 16female smigratin gE nea rcam p (6.15p.m. ) 24/3/863 2Bai ed'Aouatif ,sit e 1,migratin gN 25/3/86cal lhear dan d 1see nnea rcam p 31/3-1/4/86 ++Nouadhibo u 23/4/86cal lhear dwhe nunknow nnumbe rwa sflyin gove rcam p 27/4/86cal lhear dNouadhibo u

Coraciasgarrulu s Roller Rollier d'Europe Inth eW par to fMauritani a onlyautum npassag ei sobserve d (August-September)(Lamarch e 1987).Altenbur ge tal .(1982 )observe d1 individual inNouadhibo udurin g the 1980expedition . 6/4/86ol dcorpse ,probabl ydatin g from 1985,foun dN Epar tTidr a

Upupaepop s Hoopoe Huppefascié e Twosubspecie sar epresen ti nth ecountry ,whic hcanno tb eseparate di n thefield .I nth eN Wpar to fth ecountr yprobabl yonl y thenominat e subspecies ispresent .I ti sonl y seena sa rathe rcommo nmigran tfro m August-Octoberan dJanuary-Ma y (Lamarche 1987).Altenbur ge tal .(1982 ) observed 1-3individual s inth efirs tpar t ofFebruar ydurin g the198 0 expedition. 10/3/85+ Nouadhibo u

163 11-12/3/85+ +migratin g throughNouadhibo u 13/3/85onl ysmal lnumber slef ti nNouadhibo u 31/3/853 alon g thebeac hnea rIouik ; 1nea rcam p 2/4/85 1nea rcam p 3-4/4/85 1 Iouik 5/4/85 1Bai ed'Aouatif ,sit e6 ; 1o nairstri pnea rcam p 6/4/85 1Bai ed'Aouatif ,sit e 6; 1Nai r 7/4/85 1Ebel kAiznai ;1 Ca pTafari t 12/4/85 1Ioui k 4/5/85 1o nrubbis hti pnea rL aCherka ,Nouadhibo u 22/1/86 1beac hnea rL aCherka ,Nouadhibou ;2 Saba hhotel ,Nouadhibo u 9/2/86 1nea rcam p 15/2/86 1nea rcam p 13/3/86 1Bai ed'Aouati f migratingS E 22-23/3/86 1nea rcamp ;1 N par tBai ed'Aouati f 27-31/3/86 1nea rcam po raroun d Iouik 2/4/86 1Nouadhibo uAirpor t 3/4/86 1Ioui k 12/4/86 1Ebel kAizna i

Jynxtorquill a Wryneck Torcolfourmilie r Winteringnea rwetland si nth eS par to fMauritania .Passag ei snote di n September-Octoberan dMarch-April .I nNouakchot tautum nmigratio ni sfa r moreconspicuou s thansprin gmigratio n (Lamarche 1987). 15/3/851 Nouadhibo u into po fa telephon epol e 6/4/85 1nea rcam p

~~Lybiusviellot i Vieillot'sBarbe t Barbud evieillo t Resident inth eS par to fth ecountry ,i nrain yseason scomin gN u pt o the 17thdegre eo flatitud e (Lamarche 1987). EarlyApri l 19861 nea rcam p~~

Ammomanes cincturus Bar-tailedDeser tLar k Ammomaneélégant e Occurringa sa breedin g bird insmal lnumber sal love rth ecountr y (Lamarche 1987). 17/4/852 see nan d severalhear d indeser t So fBai ed'Aouati f 25/2/86 1S ETivid e 2/3/86 8i nAcaci afores tN Tanouder t

~~~~164 12/4/863 Ebel kAizna i 13/4/866 Tidr a~~~~

Aleamonalaudipe s HoopoeLar k Sirlid udéser t Occuringa sa commo nbreedin gbir dal love rth ecountry ,bu trar eo r absenti nth eS E(Lamarch e 1987).Altenbur g etal .(1982 )observe d 1-2i n theBai ed'Aouati fare ai nJanuar y 1980an d 1nea rCa pTafari t inMarc h 1980. Frequently 1-2i nEbel kAizna ian di nth edune s inth eN Epar to f theBai ed'Aouatif .Accordin g toou roccasiona lobservation s relatively numerousaroun d theBai ed'Aouati f butles ss ofurthe rawa y fromth e coast. 25/3/852 N Ioui k 30/3/852 N Iouik ;1 nea rcam p 31/3/85 1i ndeser tnea rcam p 17/4/852 betwee ncam pan dEbel kAiznai ;1 i nS Epar tBai ed'Aouati f 28/4/85 1Ioui k 8/2/86 2Tivid e 17/2/861 nea rcam p 24/2/86 1Fou mA lTriqu e 25/2/864 displayin gTivid e 2/3/86 1betwee nTanouder tan dNouadhibo u 6/3/86 1nea rcam p 9/4/86 1N par tTidr a 13/4/86 1Tidr a

Calandrellacinere a Red-capped Lark Alouettecalandrell e Founda sa breedin g bird inth eN par to fth ecountry .Note d onpassag e inSeptember-Ocobe r andMarch-April ,locall y inlarg eflocks .Winterin g inth eN a swel la si nth eS par to fth ecountry .Premigrator y flocksma y hold thousandso fbird s (Lamarche 1987).Altenbur g etal .(1982 )observe d 1individua lnea rCa pTimiris t duringth e 1980expedition . 14/3/85 1o nrubbis h tipnea rL aCherka ,Nouadhibo u 1/4/85 1Niroum i 14/4/85 1Ebel kAizna i 24/2/863 Fou mA lTriqu e 21/3/865 nea rcam pmigratin gN 22/3/862 N Wpar tBai ed'Aouati f 30/3/862 nea rcam p

~~~~165 5/4/86 1nea rcam p 9/4/86 1N par tTidr a 20/4/86 1alon g thecoas ta t 10k mS o fTivid e 23/4/863 i ndune snea rcam p~~~~

Ripariapaludicol a Brown-throated SandMarti n Hirondelle deMauritani e Presenta sa winterin g guesti nsmal lnumber s inth eS par to fth e country fromNovember-March .Statu slargel yunknow n (Lamarche 1987). Altenburge tal .(1982 )occasionall y observed 2-3individual snea rCa p Timiristan dTanouder t during the198 0expedition . 5/4/85 atleas t 1nea rcam p 6/4/85 2nea rcam p

Ripariaripari a SandMarti n Hirondelled erivag e Wintering inrathe rsmal lnumber snea rwetland s inth eS par to fth e country.O nmigration ,mainl ynote d inSeptembe ran d fromFebruary-May , occasionally inlarg egroups ,sometime su pt o30,00 0individual s (Lamarche 1987). 26/3/85 1Bai ed'Aouatif ,sit e1 30/3/853 nea rcamp ;+ +i nothe rplace sBai ed'Aouati f 31/3/85 3 Iouik 1/4/85 4nea rcam p 2/4/85 50-100Bai ed'Aouatif ,sit e1 3-4/4/85+ nea rcamp ;+ Iouik 5-6/4/85+ +Bai ed'Aouatif ,sit e6 an dcam p 7/4/85 +Bai ed'Aouatif ,sit e6 8-9/4/85+ nea rcam p 17/4/85+ +Bai ed'Aouati f migratingN 19/4/852 ove rse anea rIoui k 20/4/85 1Ioui k 22/4/85+ Ebel kAizna i 24/4/85 1Ioui k 16/2/86 1nea rcam pmigratin gN 14-15/3/86 1-2nea rcam pmigratin gN 20/3/865 i nE par tBai ed'Aouatif ; 1corps efound ,dea d forapprox .5 days,win g 105m m 21-24/3/86ever yda y3-1 0nea rcamp ,mos t ofthes emigratin gN 24-25/3/86 5-10betwee n Iouikan dKij i

166 30/3/86-H -alon gW shorelin eBai ed'Aouati f 31/3-3/4/864 -nea rcam p 7/4/86 1Ioui k 20/4/863 betwee nSerin ian dTivid e 21-23/4/862- 5nea rcam p 26/4/86+ L aCherka ,Nouadhibo u 27/4/86+ Nouadhibo u

~~~~Table 10.8.Weigh t (g)an dbiometrica ldat a (mm)o fa San dMarti n captured inmistnet s inth eBai ed'Aouatif ,sit e5 . date weight wing age~~~~

~~~~3/4/85 220 102 ad~~~~

Hirundorustic a Swallow Hirondelled echeminé e Onlywinterin g insmal lnumber s inth eS par to fth ecountry .Larg e numbersar esee no nmigration ,mainl yfro mAugust-Novembe ran d January-July,sometime sassemblin g inver ylarg eflock s (Lamarche 1987). Altenburg etal .(1982 )observe da nincrease d Swallowmigratio na tth e Bancd'Argui ni nth ecours eo fFebruar yan dMarc h1980 . 10/3/85+ Cansad o 11/3/85+ Nouadhibo u 14/3/853 2Nouadhibo u 15/3/852 i nlagoo nN airpor tNouadhibo u 20/3/852 nea rCa pTafari t 21/3/85 2Te nAllou l 24/3/853 nea rcamp ;6 0i nth eBai ed'Aouatif ;i nth eafternoo n 15Bai e d'Aouatif migratingN ;1 Ebel kAizna i 25/3/853 nea rcamp ;1 1Ioui k 28/3/85 10Bai ed'Aouati f 29/3/85 18Ebel kAizna i 30/3/853 0migratin gN Iouik ;4-H -Bai ed'Aouati f 31/3/8540 0foragin g Baied'Aouatif ,sit e3 ,graduall ymigratin gN 1/4/85 +4-nea rcam p 2/4/85 300Bai ed'Aouatif ,sit e1 3-4/4/85 + Iouik;-H -nea rcamp ;everywher e inth eSahar abetwee n

167 Nouadhibouan dIoui k 5/4/85 +++stron gmigratio nN everywher e inBai ed'Aouati f 6/4/85 200aroun d camp 7-10/4/85 ++nea rcam p 11-13/4/85 10betwee ncam pan dIoui k 14/4/853 Chamie ;+ +Ebel kAiznai ;10-2 0nea rcam p 17/4/85+ W par tBai ed'Aouati f 18/4/85+ camp ;8 0i non efloc kN Epar tBai ed'Aouati f 20/4/85 1Iouik ;+ betwee ncam pan d site1 22/4/856 5Ebel kAizna i 23/4/855 Niroum i 25/4/85-H -E par tBai ed'Aouati f 27/4/85+ Ioui k 1/5/85 + lied'Argui n 4-5/5/85 +++Nouadhibo u 22/1/86 10Saba hhotel ,Nouadhibo u 7/2/865 nea rcam p 8-22/2/86u pt o 10nea rcamp ,frequentl y seenmigratin gN 19/2/863 Ebel kAizna i 23/2-12/3/86u pt o5 alon g theW shorelineo fth eBai ed'Aouati f 13-15/3/86+ +nea rcam pmigrati:. ^N 14/3/86++ +nea rcam pmigratin gN ,spendin g thenigh ti nexpeditio ntent s 16-17/3/86number snea rcam pdecreasin ga scompare d topreviou sday s 18-19/3/86+ nea rcamp ;+ alon gW par tBai ed'Aouatif ; 1Tivid e 20/3/86+ +nea rcam pmigratin gN 21-23/3/86++ +nea rcam pmigratin gN 24/3/86 100-200betwee nIoui kan dKij imigratin gN 25/3/86 10-50betwee nRgueïb aan dZir amigratin gN 26/3-1/4/86+ +nea rcam p 2/4/86 +++betwee n Iouikan dTidr a 3-19/4/86+ +cam p 7/4/86 1Are l 8/4/86 4N EAre l 13/4/86 15N par tTidra ; 1Niroum i 20/4/86 100Serini ;5 0Tivide ;3 0N Wpar tBai ed'Aouati f 21/4/86++ +alon gshorelin eW par tBai ed'Aouati f 22-23/4/86 50-100alon g shorelineW par tBai ed'Aouati f 25/4/86 + He d'Arguin

~~~~168 26/4/86++ +Nouadhibo u~~~~

~~~~Table 10.9.Weigh t (g)an dbiometrica ldat a (mm)o f Swallowscapture di n mistnetsnea rth ecam po rb yhan d inth ecam pitsel f date weight wing sex age fatscor e~~~~

31/3/85 130 121 male ad. 0 31/3/85 180 122 male ad. 0 1/4/85 205 117 female ad. 0 1/4/85 173 117 female ad. 0 2/4/85 150 120 female ad. 0 3/4/85 193 125 male ad. 4 8/4/85 138 119 female 2nd c.y. 0 14/3/86 157 121 male 2 14/3/86 157 120 female ad. 3 14/3/86 130 122 male ad. 0 18/3/86 139 120 female ad. 0 21/3/86 150 119 ad. 0 21/3/86 163 123 male ad. 0 21/3/86 159 122 ad. 0 21/3/86 162 124 male ad. 0 21/3/86 161 123 female ad. 0 22/3/86 164 119 female ad. 3 22/3/86 148 122 female 0 31/3/86 116 117 female ad. 0

~~~~169 Table 10.10.Biometrica ldat a (mm)o fSwallow sfoun ddea d inan daroun d thecamp ,th eBiologica l Stationan d inIoui k date wing sex age fatscor e~~~~

~~~~11/4/85 126 male 0~~~~

11/4/85 female 2nd c.•y « 0 11/4/85 female 2nd c.-y « 0 12/4/85 123 male ad. 16/4/85 130 male 0 19/4/86 125 male ad. 0 19/4/86 120 male 21/4/86 118 female ad. 21/4/86 120 female ad. 21/4/86 121 male ad. 0 21/4/86 123 female 2nd c.•y « 0 21/4/86 125 female 2nd c..y . 0 21/4/86 123 male ad. 0 21/4/86 123 female ad. 0 21/4/86 124 male ad. 21/4/86 125 male ad. 21/4/86 122 male ad. 21/4/86 119 male 2nd c •y . 21/4/86 121 male 2nd c •y « 0

Hirundodauric a Red-rumped Swallow Hirondelle rousseline Two subspeciesar epresen ti nth ecountry ,on eo fthes ebein grar ean d onlyoccurrin g inth eextrem eS o fth ecountry . H.d. rufulai sa migrant,see ni nrathe r smallnumbers ,i nOctober-Novembe ran dMarch-Jun e (Lamarche 1987).Altenbur g etal .(1982 )observe d 1individua lnea rCa p Tafarit (5/3/80)durin g the 1980expedition . 10/3/85 1Cansad o 13/3/852 0Ca pBlan c 5/4/85 1-2airstri pW par tBai ed'Aouati f 6/4/85 10nea rcamp ;3 Bai ed'Aouatif ,sit e6 13/3/86 1Bai ed'Aouatif ,sit e5 22-23/3/86 9-10nea rcam p 170 24/3/86 1nea rcam p 31/3/86 1nea rcam p 2-3/4/86 2nea rcam p 12/4/86 1Ebel kAizna i 21/4/86 1corps e foundnea rBiologica l Station,dea d forabou t 2weeks , wing 119m m

~~~~Table 10.11.Weigh t (g)an d biometricaldat a (mm)o fa Red-rumpe d Swallow captured ina mistne tnea r thecam p date weight wing age fatscor e~~~~

~~~~22/3/86 182 119 2ndc.y . 2~~~~

Delichonurbic a HouseMarti n Hirondelled efenêtr e Wintering inver y smallnumber si nth eS par to fth ecountry .Autum n passage (October)i sno tver yconspicuous .Number s seendurin gsprin g passage (February-June)ar esomewha t larger.Mos tbird ssee mt ous ea routethroug h theinterio rpar to fth ecountr y (Lamarche 1987).Altenbur g etal .(1982 )onl yobserve d 2individual sa t theBan cd'Argui n duringth e 1980expedition . 10/3/85+ Cansad o 13/3/85 1Ca pBlan c 29/3/85 1Ioui k 31/3/85 7nea rcamp ;3 Ioui k 1/4/85 2nea rcam p 2/4/85 10Bai ed'Aouatif ,sit e1 3/4/85 + Iouik;+ nea rcamp ;a tleas t 10Nouadhibo u 5-6/4/85 ++camp ;+ +Ioui k 7/4/85 +nea rcam p 11/4/85 1nea rBiologica l StationIoui k 14-18/4/85u pt o5 migratin gN nea rcam p 4/5/85 1Nouadhibo u 3/2/86 1Nouadhibo u 7/2/86 1Ebel kAizna i 15/2/863 nea rcamp ,migratin gN 14/15/3/86 1-2nea rcam p

171 20/3/863 alon gW par tBai ed'Aouati f 21-25/3/865-1 0nea rcamp ,migratin gN 24-25/3/86+ betwee nIoui kan dKij i 30/3/86+ +N par tBai ed'Aouati f 3/4/86 1nea rcam p 7/4/86 1femal e found inse anea rCa pTafarit ,win g 106m m 8/4/86 1nea rcam p 20/4/86 1a t2 0k mS Tivide ; 1N Wpar tBai ed'Aouati f 21-22/4/862 nea rcamp ;2 N Wpar tBan cd'Argui n 26/4/86+ +Nouadhibo u

Anthuscampestri s TawnyPipi t Pipitrousselin e Present inmos to fth ecountr y throughout theyear .Breedin gpossibl ebu t notye tcertain .Passag ei nSeptember-Octobe ran dMarch-Ma y (Lamarche 1987). 14/3/852 L aCherka ,Nouadhibou ;6 o nnearb y rubbishti p 30-31/3/85 1-2Ebel kAizna i 1/4/85 1Niroum i 6/4/85 1Bai ed'Aouatif ,sit e6 9/4/85 1Ebel kAizna i 14/4/85 1Ebel kAizna i 23/3/862 Bai ed'Aouatif ,sit e2 3/4/86 2Bai ed'Aouatif ,sit e5 9/4/86 1N par tTidr a 13/4/862 W par tTidr a 20/4/863 betwee nSerin ian dTivid e 23/4/861 nea rcam p

Anthustriviali s TreePipi t Pipitde sarbre s Wintering inrathe rsmal lnumber si nth eS par to fth ecountry .A rathe r commonmigrant ,see nmainl yfro mSeptember-Novembe r andMarch-Jun e (Lamarche 1987). 10/3/85 1garde nNouadhibo u 12/3/85 1L aCherka ,Nouadhibo u 14/3/855 garde naroun d Sabahhotel ,Nouadhibo u 15/3/85 15L aCherka ,Nouadhibo u 30/3/85 1Ioui k 31/3/85 1Iouik ;5 Ebel kAizna i

172 1/4/85 1 Niroumi 2-5/4/85 1-2 near camp 3/4/85 2 Iouik 11-13/4/85 1Ioui k 17/4/852 W par tBai ed'Aouati f 14/3/86 1nea rcamp ;2 Bai ed'Aouatif ,sit e1 25/3/862 Rgueïba ,migratin gN 1/4/86 1nea rcam p 2/4/86 3nea rcamp ;2 N Wpar tBai e d'Aouatif 5/4/86 1nea rcam p 9/4/86 2N par tTidr a 26/4/86+ L aCherka ,Nouadhibo u

~~~~Table 10.12.Weigh t (g)an dbiometrica ldat a (mm)o fTre ePipit scapture d inmistnet snea rth ecam p date weight wing age fatscor e~~~~

~~~~16/3/85 26.5 90 4 28/3/86 15.0 87 ad. 0~~~~

Anthuspratensi s MeadowPipi t Pipitfarlous e Smallnumber sar ewinterin g inMauritania ,rarel yi nth eE par to fth e country.Passag e isnote d fromSeptember-Novembe r and inFebruary-Marc h (Lamarche 1987). 31/1/86 1L aCherka ,Nouadhibo u 9/4/86 1N par tTidr a

Anthuscervinu s Red-throated Pipit Pipità gorg erouss e Wintering invegetate d partso f thecountry ,mainl y So fth e 21stdegre e oflatitude .Passag e fromSeptember-Novembe r andMarch-May ,i nautum n mainly inth eE par to fth ecountry ,i nsprin gmainl yi nth eW par t (Lamarche 1987).Altenbur ge tal .(1982 )onc e (7/3/80)observe d 5 Red-throated Pipitsnea rCansad odurin g the 1980expedition . 11/3/852 0L aCherka ,Nouadhibo u 14/3/85 15o nrubbis h tipnea rL aCherka ,Nouadhibo u 30/3/85 1Ebel kAizna i

17 A 8/4/85 2Ebel kAizna i 11/4/851 Ioui k 27/4/85 1i nsumme rplumag eEbelk .Aizna i 4/5/85 1i ngarde nNouadhibo u 5/5/85 1L aCherka ,Nouadhibo u 22/1/866 Beac hnea rL aCherka ,Nouadhibo u 31/1/865 Beac hnea rL aCherka ,Nouadhibo u 16-17/4/86 1nea rcam p 21/4/86 1nea rcamp ;1 i nN Wpar tBai ed'Aouati f 24/4/861 nea rcam p 27/4/863 L aCherka ,Nouadhibo u

Motacillaflav a YellowWagtai l Bergeronnette printanière Sixsubspecie sma yb eme ti nMauritania ,M.f .flav abein g themos t numerous.Thousand so fYello wWagtail sar ewinterin g inth eS par t ofth e country,bu twinterin g individualsma yals ob efoun dalon g thecoas tan d inNouakchott .Th esubspecie scompositio n inth ewinterin gareas , however,stil li spoorl yknown .Al lsubspecie sar eobserve d onmigration , M.f. flavai nAugust-Septembe ran dMarch-April ,"flavissima "(rathe r common)fro mAugust-Octobe r andi nMarch ,"iberiae "(smal lnumbers )i n August-Septemberan dFebruary-Mars" h(als opresen ta sa breedin g bird), "cinereocapilla" (smallnumbers )fro mAugust-Octobe ran dMarch-April , "thunbergi" (verysmal lnumbers )i nSeptember-Octobe r andApri lan d "feldegg" (rare)i nOctobe ran dMarc h (Lamarche 1987).Altenbur g etal . (1982)observe d upt o3 0(mainl y fromearl yJanuar y tomi dFebruary ) YellowWagtail sa tth eBan cd'Argui ndurin g the198 0expedition . 11/3/85+ o nsevera lplace sNouadhibo u 12/3/85 1L aCherka ,Nouadhibou ,probabl y"iberiae " 14/3/85 1mal e"flavissima "o nrubbis h tipnea rL aCherka ,Nouadhibou ; alsopresen there :+ "iberiae "an d 5M .flav asp. , 15/3/852 L aCherka ,Nouadhibo u 22/3/85 1mal ean d 1female ?alon gbeac hi nE par tBai ed'Aouati f 28-29/3/85 1Iouik ; 1alon g thebeac hnea rIoui k 30/3/85 1mal ean d 3male s"flava "nea rcamp ; 10nea rcam pmigratin gN 31/3/85 12Ebel kAizna i 1/4/85 4nea rcamp ,amon gwhic h 1"flavissima " 2/4/85 2Nai r 3/4/85 10Iouik ;8 Ebel kAizna i

174 5/4/85 ++nea rcamp ,amon gwhic h"flava " 6/4/85 atleas t 6"flavissima "Bal ed'Aouatif ,sit e6 ; 1M .flav asp . nearcam p 7/4/85 -H-nea rcam p 8/4/85 5Ebel kAiznai ;4 nea rcam p 9-22/4/85a tleas t 2Ebel kAizna i 12/4/85 1mal e"flavissima "Ioui k 13/4/853 nea rcamp ;+ Ioui k 14/4/854 Ebel kAiznai ;1 "flava "W par tBai ed'Aouati f 18-22/4/852 nea rcamp ;1 Ioui k 19-23/4/853 Nai r 23/4/85+ +Niroumi ,al lmale s"flava " 25/3/85+ E par tBai ed'Aouati f 27/4/85 1Ebel kAizna i 1/5/85 +N Epar tH e d'Arguin 15-19/2/86 1nea rcam p 22/2/86 1mal e "iberiae"Ebel kAiznai ;1 flav asp .nea rcam p 25/2/861 nea rcam p 28/2/863 "iberiae "Ebel kAizna i 8-12/3/861- 2nea rcam p 14/3/86 10"iberiae" ,1 0"flava "an d 1"flavissima "nea rcam p 15/3/863 nea rcamp ;2 Ioui k 20/3/86 1nea rcamp ;1 alon gW par tBai e d'Aouatif 22/2/862 Ajoueï r 22-23/3/86 10-20nea rcamp ,amon gwhic h 1"iberiae " 24/3/8625-5 0betwee nIoui kan dKiji ,amon gwhic h"flavissima " 25/3/86 10-50betwee nRgueïb aan dZir a 26-29/3/86 1-3nea rcamp ;1 "thunbergi "Ioui k 30/3/86 15"iberiae "an d "thunbergi"nea rBiologica l Station 31/3/86abou t 100Bai ed'Aouatif ,sit e1 1/4/86 10-20migratin g alongcamp ,amon gwhic h 1"flava "an d 2 "thunbergi" 2/4/86 2"flavissima "alon gW par tBai e d'Aouatif 3/4/86 4nea rcamp ;2 Iouik ;1 Tidr a 4-27/4/86u pt o5 nea rcam p 6/4/86 1"thunbergi "Ioui k 9/4/86 20N par tTidr a 20/4/86 1betwee nSerin ian dTivid e 175 26-27/4/86+ L aCherka ,Nouadhibou ,amon gwhic h 1"thunbergi "

~~~~Table 10.13.Weigh t (g)an dbiometrica ldat a (mm)o fa Yello wWagtai l captured ina mistne tnea rth ecam p date weight wing age fatscor e~~~~

~~~~4/4/86 17.2 78 2ndc.y. ? 3~~~~

Motac11lacinere a GreyWagtai l Bergeronnettede sruisseau x Smallnumber sar ewinterin gnea rwetland s inth eS par to fth ecountry . Passagefro mAugust-Octobe ran dApril-Ma y (Lamarche 1987). 12/3/85 1L aCherka ,Nouadhibo u 16/2/86 1nea rcam p 26/4/861 4L aCherka ,Nouadhibo u

Motacillaalb a WhiteWagtai l Bergeronnettegris e Largenumber sar ewinterin galon g thecoas t (1000a tth eBan cd'Arguin) , inth eSénéga ldelt aan delsewher e inth eS par to f thecountry .Passag e fromSeptember-Novembe r andi nFebruary-Marc h (Lamarche 1987).Altenbur g etal .(1982 )observe d someten sforagin g inNouadhibo ui nmid-January , upt o2 i nIoui ki nth ecours eo fJanuary-Februar y andu pt o 5elsewher e at theBan cd'Argui n duringth e 1980expedition .Observation s in1985/8 6 atth eBan cd'Argui n become lessnumerou si nth ecours eo fApril .Al l sightings refer toth esubspecie sM.a .alba ,excep t forthos eindicate d subspecifically. 10-20/3/85+ +Nouadhibo u 25/3/85 1Ioui k 31/3-3/4/852 Ioui k 5-6/4/85 1Bai ed'Aouatif ,sit e6 7/4/85 1nea rcam p 8/4/85 1Ebel kAizna i 11-13/4/85 2 Iouik 14/4/85 1nea rcamp ;1 Ioui k 19-20/4/85 1Iouik ;4 nea rcam p 21/4/85 1nea rcam p 22/1/862 0Nouadhibo u

176 2-4/2/86+ +Nouadhibou ,severa lplace s 6-7/2/861 nea rcam p 8/2-7/3/862- 5nea rcamp ;+ Ebel kAiznai ;0- 1Ioui k 16/2/86+ +nea rcam p 24-25/2/86 1Teïcho t 3/3/86 10L aCherka ,Nouadhibo u 8-9/3/861 nea rcam p 10/3-2/4/86generall y 2,occasionall y upt o5 nea rcamp ;0- 4 Iouik 24-25/3/865-1 0betwee nIoui kan dKij i 2/4/86 6L aCherka ,Nouadhibo u 2-14/4/86 1-2nea rcam p 3/4/86 2ver ydar kWagtail snea rcamp ,possibl yM.a .subpersonata ;1 M.a.alb aIoui k 9/4/86 10N par tTidr a 16/4/86 1Ioui k 20/4/86 1Tivid e 21/4/86 1Ioui k

~~~~Table 10.14.Weigh t (g)an dbiometrica ldat a (mm)o fa Whit eWagtai l captured ina mistne tnea rth ecam p date weight wing sex age fatscor e~~~~

~~~~15/4/86 15.6 83 male 2ndc.y . 0~~~~

Lusciniamegarhyncho s Nightingale Rossignolphilomèl e Probablyno t presenta sa winterin g guest.Passage ,mainl y inth eW par t ofth ecountry ,fro mAugust-Octobe r andFebruary-Apri l (Lamarche 1987). 31/3/852 i ncam pIoui k 1/4/85 1i ncam p (intent ) 17/4/85 1nea rcam p 9/4/86 1N par tTidr a 17/4/86 1corpse ,dea d forsevera lweeks ,Biologica l Station

~~~~Luscinia svecica Bluethroat Gorgebleu e Smallnumber sar ewinterin g inth eSénéga ldelt aan delsewher ei n wetlands inth eS par to f thecountry .Passag efro m September-November~~~~

~~~~177 andMarch-Apri l (Lamarche 1987). 10/3/85 1femal eL aCherka ,Nouadhibo u 21/3/85 1mal ealon g thebeac hTe nAllou l 4/4/85 1whitebreaste dEbel kAizna i~~~~

Phoenicurusochruro s BlackRedstar t Rouge-queuenoi r Occasionalvisito r toMauritani a (Lamarche 1987). 5/4/85 1nea rcamp ;+ +Nai r 7/4/85 2male san d 1femal eCa pTafari t 22/1/86 1mal eSaba hhotel ,Nouadhibo u 28/3/86 1femal enea rcam p

Phoenicurusphoenicuru s Redstart Rouge-queueà fron tblan c A commonwinterin ggues talon g theSénéga lriver .Passag ei snote d throughout thecountry ,mainl y fromAugust-Novembe ran dFebruary-Jun e (Lamarche 1987). 30/3/85 1femal ecatchin g fliesi nhous eIoui k 31/3/85 2male san d 1femal enea rcam p 3/4/85 1mal eIoui k 4-6/4/85 1mal enea rcam p 1/4/86 1Nouadhibo u

~~~~Table 10.15.Weigh t (g)an dbiometrica ldat a (mm)o fa Redstar t captured ina mistne tnea r thecam p date weight wing sex age fatscor e~~~~

~~~~31/3/85 11.1 69 male 2ndc.y . 2~~~~

Saxicolarubetr a Whinchat Traquet tarier Rather smallnumber sar ewinterin galon g theSénéga lriver ,mos tbird s presenther ei nautum nmigratin g furtherS .Passag efro mAugust-Novembe r andApril-Ma y (Lamarche 1987). 3/4/85 1Ebel kAizna i 4-5/4/851- 2nea rcam p 17/4/85 1nea rcam p 20/4/86 1ad .mal eN Wpar tBai ed'Aouati f

~~~~178 26/4/86 1mal eL aCherka ,Nouadhibo u~~~~

~~~~Table 10.16.Weigh t (g)an dblometrica ldat a (mm)o fa Whincha tcapture d ina mistne tnea r thecam p date weight wing age fatscor e~~~~

~~~~4/4/85 14.0 73 ad. 2~~~~

Saxicola torquata Stonechat Traquetpatr e Rarea sa winterin g guesta swel la sdurin gmigration ,number svaryin g strongly fromyea rt oyea r (Lamarche 1987). 5/4/85 1mal eBai ed'Aouatif ,sit e6 23/1/86 1mal eSaba hhotel ,Nouadhibo u

Oenantheoenanth e Wheatear Traquetmotteu x Four subspeciesma yb eencountere d inMauritania ,O.o .oenanth ebein gth e mostnumerous .Bird swinterin g inth ecountr yprobabl ymostl yar eO.o . seebohmian dpossibl yO.o .libanotica .O.o .oenanth e isobserve d asa migrant fromSeptember-Novembe r andFebruary-March ,"leucorhoa "i s relatively scarcefro mSeptember-Novembe r and inMarch ."Seebohmi "i s noted onpassag e inNovembe ran d inFebruary-March ,"libanotica "i s mostlysee ni nOctobe ran dNovembe ran dpossibl yi nFebruar y (Lamarche 1987).Altenbur g etal .(1982 )observe d 1Wheatea r inCansad oi nMarc h during the 1980expedition . 11/3/853 Nouadhibo u 12-15/3/85 1-2L aCherka ,Nouadhibo u 21/3/85 1Te nAllou l 30/3/852 male s Iouik; 1mal enea rcamp ; 1mal eEbel kAiznai ; 1femal e (probablyO. o leucorrhoa)Bai ed'Aouatif ; 1mal eBai ed'Aouatif ,sit e3 31/3/852 Ebel kAizna i 3/4/85 1mal ean d 1femal eIouik ; 1mal enea rcam p 5/4/85 atleas t 5,ou to fwhic h3 males ,Bai ed'Aouatif ,sit e6 6/4/85 1mal eBai ed'Aouatif ,sit e 6;1 0nea rcam p 7/4/85 1femal eEbel kAiznai ;1 femal enea rcam p 8/4/85 2male sEbel kAizna i 14/4/853 Ebel kAizna iou to fwhic h 2male sO.o .seebohm i

179 19/4/85 1mal enea rcam p 31/1-3/2/86 1rubbis h tipnea rL aCherka ,Nouadhibo u 23/3/86 1mal ean d 1femal eairstri pW par tBai ed'Aouati f 24/3/862 female sKij i 25/3/86 1mal eBai ed'Aouatif ,sit e1 31/3/86 1nea rcam p 1/4/86 1Iouik ; 1Nouadhibo u 2-3/4/861 mal eO.o .seebohm iIoui k 2/4/86 2L aCherka ,Nouadhibo u 4-5/4/861 femal enea rcam p 5/4/86 1mal eIoui k 7-11/4/861 femal eIoui k 17/4/86 1femal eBiologica lStatio n

Oenanthehispanic a Black-earedWheatea r Traquetoreillar d Twosubspecie sar epresen ti nMaurutania .O.h .hispanic ai sa commo n winteringgues t inth eS par to fth ecountr yan d seeno npassag efro m September-Novemberan di nFebruary-March .O.h .melanoleuc ai spassin g throughi nver y smallnumber s inOctober-Novembe ran d inApri l(Lamarch e 1987). 5/4/85 1mal eBai ed'Aouatif ,sit e6 14/3/862 male snea rcam p 18/3/86 1mal eBai ed'Aouatif ,sit e3 21/3/86 1mal enea rcam p 22/3/86 1mal eBiologica lStation ;3 nea rairstri pW par tBai ed'Aouati f

Oenanthedesert i DesertWheatea r Traquetd udeser t Winteringgues tan dbreedin gbir d inMauritania ,presen t throughoutth e country.Observe d atth eBan cd'Argui n fromSeptember-Novembe r andi n March-April (Lamarche 1987),bu tdurin gth e 1986expeditio nals oobserve d asa winterin ggues ti nNouadhibo uan da tth eBan cd'Arguin .Altenbur ge t al. (1982)observe d 3Deser tWheatear s inNouadhibo u inJanuar y1980 , someten si nth edeser tbetwee nNouadhibo uan d theBan cd'Argui nan d 1i n Iouiki nJanuar y1980 . 22/1/863 singin gmale s rubbishti pnea rL aCherka ,Nouadhibo u 3/2/86 1mal eL aCherka ,Nouadhibo u 7-13/2/86 1 male near camp 8/2/86 1femal eTivide ; 1femal eEbel kAiznai ;1 femal eN Wpar tBai e

~~~~180 d'Aouatif 14/2-13/3/86 1mal eIoui k 18/2/86 1Tivid e 22/2/86 1femal eEbel kAizna i 3/3/86 1mal eL aCherka ,Nouadhibo u 8/3/86 1mal enea rcam p~~~~

~~Oenantheleucopyg a White-crowned BlackWheatea r Traquetà têt eblanch e Occurring throughout theSahe lan dSahara ,generall yN o fth e 18thdegre e oflatitud e (Lamarche 1987). 23/2/86 1S ti pTidr a~~

~~~~Monticolasaxatili s RockThrus h Merled eroch e Arar egues tt oMauritania ,mainl y fromSeptember-Apri l (Lamarche 1987). 5/4/85 1ad .mal esebk anea rIoui k~~~~

Turdusphilomelo s SongThrus h Grivemusicienn e Arar egues t toMauritania ,mainl y fromNovember-Februar y (Lamarche 1987). 14/3/85 1i nbushe snea rSaba hhotel ,Nouadhibo u 30-31/1/86 1i ngarde nSaba hhotel ,Nouadhibo u

Locustellanaevi a GrasshopperWarble r Locustelle tachetée Locallycommo na sa winterin g guest,mainl ybetwee nNouakchot t andth e Chott'Boulan dalon g thecoast .Passag efro mAugust-Octobe ran di n February-March.Sprin gmigratio n isver yinconspicuou s (Lamarche 1987). 4/4/85 1garde nNouadhibo u 5/4/85 +nea rcamp ;1 Ebel kAizna i 7/4/85 feather remainso feate nbir dTe nAllou l 10/4/85 1i nhous eIoui k 14/4/85 1nea rcam p 23/1/86 1garde nSaba hhotel ,Nouadhibo u

Acrocephalus schoenobaenus SedgeWarble r Phragmitede sjonc s Wintering insmal lnumber s inth eSénéga ldelt aan dwetland selsewher ei n theS par to f thecountry .Passag ei nSeptember-Octobe r andfro m February-June(Lamarch e 1987). 22/1/86 1i ngarde nSaba hhotel ,Nouadhibo u

181 Locustellaluscinioide s Savi'sWarble r Locustelle luscinioide Smallnumber ssometime sar ewinterin galon gwetland si nth eS par to fth e country.Autum nmigratio n isnote d inSeptember-October ,sprin gmigratio n isver yinconspicuou s (Lamarche 1987). 6/4/85 1nea rcam p

Hippolaispolyglott a MelodiousWarble r Hypolaispolyglott e Uncertainwhethe rth especie si swinterin g inS Mauritania .Passage , mainlyobserve d inth ecoasta lregion ,fro mAugust-Octobe ran d March-April 6/4/85 3Nai r 21-23/4/86 1nea rcam p

~~~~Table 10.17.Weigh t (g)an dbiometrica ldat a (mm)o fa Melodiou sWarble r capturednea r thecam p date weight wing age fatscor e~~~~

~~~~4/4/85 10.7 70 ad. 0~~~~

Sylviaconspicillat a SpectacledWarble r Fauvetteà lunette s Commona sa winterin g guestalon g thecoast ,S o fth e 183 0degre eo f latitude.Smal lnumber sar ewinterin g inland,throughou t thecountry . Passagefro mAugust-Octobe r and inMarc h (Lamarche 1987). 22/1/86 1mal ean d 2female sNouadhibo u

~~~~Table 10.18.Weigh t (g)an dbiometrica ldat a (mm)o fa Spectacle dWarble r captured ina mistne ti nth ecam p~~~~

~~~~date weight wing age fatscor e~~~~

~~~~8/4/86 7.7 55 ad. 1~~~~

~~~~Sylviacantillan s SubalpineWarble r Fauvettepasserinett e Wintering inrathe rsmal lnumbers ,mainl y inth eS par to fth ecountry .~~~~

182 Passagei nSeptember-Octobe r andi nMarc h (Lamarche 1987).Altenbur ge t al. (1982)observe d singleindividual sa t theBan cd'Argui no ntw oday s inFebruar y during the 1980expedition . 6/4/85 1nea rcam p 4/5/85 1i ngarde nNouadhibo u 20/2/86 1nea rcam p

~~~~Table 10.19.Weigh t (g)an dbiometrica ldat a (mm)o fa Subalpin eWarble r captured inmistnet snea r thecam p date weight wing age fatscor e~~~~

~~~~4/4/85 8.8 56 2ndc.y . 3~~~~

Sylviamelanocephal a SardinianWarble r Fauvettemélanocéphal e Wintering inrathe rsmal lnumbers ,mainl y inth eS par to f thecountry . Rarei nth eE .Passag ei nSeptember-Novembe r and fromFebruary-Apri l (Lamarche 1987). 22/1/86 1mal ean d 2female sNouadhibo u 2/3/86pai ri nAcaci a forestN Tanouder t

Sylviacommuni s CommonWhitethroa t Fauvettegrisett e Arathe rcommo nwinterin g guest,mainl yi nth eS par to fth ecountry . Passagei nAugust-Octobe ran di nApril-Ma y (Lamarche 1987). 8/4/86 1Bai ed'Aouatif ,sit e1

~~~~Table 10.20.Weigh t (g)an dbiometrica ldat a (mm)o fa Commo nWhitethroa t captured inmistnet snea rth ecam p date weight wing sex age fatscor e~~~~

~~~~3/4/85 11.4 74 female? ad. 0~~~~

~~~~Sylviabori n GardenWarble r Fauvettede sjardin s Wintering inrathe rsmal lnumbers ,mainl y inth ecentra lpar t ofth e country,absen t inth eS part .Passag e inAugust-Novembe ran dfro m~~~~

~~~~183 March-May (Lamarche 1987). 8/4/85 1nea rcam p 16/4/85 1nea rcam p 16/4/86 1nea rcamp ; 1Ioui k~~~~

~~~~Table 10.21.Weigh t (g)an dbiometrica l data (mm)o fa Garde nWarble r captured inmistnet snea rth ecam p date weight wing age fatscor e~~~~

~~~~4/4/85 24.6 79 ad.~~~~

Sylviaatricapill a Blackcap Fauvetteà têt enoir e Smallnumber sar ewinterin g inwoode d orshru barea si nth ecentra lan dS parto fth ecountr yan dalon gwetland si nth eSahe lzone .Commo no n passagei nOctober-Novembe r and fromFebruary-Jun e (Lamarche 1987). 4-5/4/851 mal enea rcam p 6/4/85 1femal enea rcamp ;1 femal eeate nb yKestre l 7/4/85 1mal e inten ti ncam p 14/4/85 1mal eEbel kAizna i 16/4/85 1nea rcam p 22/1/86 1mal egarde nSaba hhotel ,Nouadhibo u 2/3/86 1mal egarde nSaba hhotel ,Nouadhibo u 23/3/86 1mal eBai ed'Aouatif ,sit e6 24/3/86 1mal enea rcam p 31/3/86 1femal enea rcam p 3/4/86 1femal enea rcam p 7/4/86 1mal eBai ed'Aouatif ,sit e1 16/4/86 1mal enea rcamp ;1 mal eBai ed'Aouatif ,sit e5 ;1 femal eIoui k 17/4/86 1mal enea rcamp ; 1femal eNiroum i 21-22/4/86 1femal enea rcamp ;1 femal eIoui k 27/4/86 1femal egarde nNouadhibo u

~~~~184 Table 10.22.Weigh t (g)an dbiometrica ldat a (mm)o fa Blackca pcapture d inmistnet snea r thecam p date weight wing sex age fatscor e~~~~

~~~~3/4/85 24.5 73 male ad. 5~~~~

PhylloscopusboneH i Bonelli'sWarble r Pouillotd eBonell i Smallnumber sar ewinterin g So f the 17thdegre eo flatitude .Passag e fromAugust-Octobe ran dFebruary-Apri l (Lamarche 1987). 5-6/4/85 1nea rcam p 18/4/851 nea rcam p 14-15/3/86 1nea rcam p 26/4/86 1L aCherka ,Nouadhibo u

~~~~Table 10.23.Weigh t (g)an dbiometrica l data (mm)o fa Bonelli' sWarble r captured inmistnet snea rth ecam p~~~~

~~~~date weight wing age fatscor e~~~~

~~~~14/3/86 8.1 66 ad. 3~~~~

Phylloscopuscollyblt a Chiffchaff Pouillotvèloc e Commonwinte rvisito r inarea smor eo rles sclos et oth ewater .Passag e inOctober-Novembe r andJanuary-Jun e (Lamarche 1987).Altenbur g etal . (1982)observe d 1singin gChiffchaf f inNouadhibo u inMarc h1980 . 10/3/851 i ngarde nNouadhibo u 11/3/85+ +o nsevera lplace sNouadhibo u 13/3/85 1i ngarde nNouadhibo u 29/3/852 Ioui k 30/3/85 1Ebel kAizna i 2-5/4/85 ++nea rcam p 18/1/86 5i ngarde nSaba hhotel ,Nouadhibo u 3/2/86 ++i ngarden sNouadhibo u 8/2/86 1Tivid e 10/2-19/3/86+ nea rcam p

~~~~185 22/2/86 5Ebel k Aiznai 25/2/86 1Tivid e 26/2-15/3/86 + Iouik 22-23/3/86 50-100 near camp 29/3-6/4/86 1-5 near camp~~~~

~~~~Table 10.24.Weigh t (g)an d biometrical data (mm) of Chiffchaffs captured in mistnets near the camp~~~~

~~~~date weight wing age fatscor e~~~~

13/3/85 8.8 55 4 13/3/85 11.0 63 3 1/4/85 6.0 58 ad. 0 2/4/85 7.4 56 ad. 3 4/4/85 5.9 55 ad. 0 4/4/85 6.9 56 ad. 3 6/4/85 5.6 63 0 10/2/86 6.5 59 ad. 3 11/2/86 7.2 63 0 16/2/86 8.0 63 ad. 3 21/3/86 5.5 58 ad. 0 23/2/86 7.1 62 ad. 0 14/3/86 7.1 54 ad. 5

t_/../?/« * (•.,f 57 p.d. 2 15/3/86 5.8 56 ad. 0 15/3/86 5.7 56 ad. 0 15/3/86 6.8 63 ad. 0 21/3/86 7.2 56 ad. 4 22/3/86 5.5 56 ad. 0 22/3/86 5.5 55 1 22/3/86 5.9 58 ad. 0 22/3/86 7.5 61 ad. 3 22/3/86 5.7 56 ad. 0 23/3/86 5.7 55 ad. 0 23/3/86 6.5 54 0 24/3/86 5.4 55 0 29/3/86 6.1 56 ad. 2 30/3/86 7.8 69 ad. 0 30/3/86 6.2 65 ad. 0 31/3/86 6.9 57 ad. 0 31/3/86 5.0 56 ad. 5/4/86 5.7 58 ad. 0

186 Phylloscopus trochilus WillowWarble r Pouillotfiti s Rathercommo nwinte rvisito rnea rwetland sal love rth ecountry .Passag e fromAugust-Novembe ran di nJanuary-Februar y (Lamarche 1987). 13-15/3/85+ +garden san dL aCherka ,Nouadhibo u 30/3/85 1Iouik ; 1Ebel kAizna i 31/3/85 1captured ,ringe d 21/4/84Bardse y Isl.,Wales ;3 Ioui k 1/4/85 at least4 aroun dcam p 5-6/4/85 -H-+everywher earoun d thecamp ,frequentl y feeding intent s 7/4/85 4nea rcamp ;1 Ebel kAizna i 18/4/851 Bai ed'Aouatif ,sit e5 23/4/852 Niroum i 1/5/85 1li ed'Argui n 22/1/86 10garde nSaba hhotel ,Nouadhibo u 14-20/3/86 + near camp 22-23/3/8650-10 0nea rcam p 24/3/863 0S par tKij i 24-26/3/86 3-5nea rcam p 29/3-3/4/86 1-3nea rcam p 13/4/862 N par tTidr a 20/4/863 betwee nSerin ian dTivide ,foragin galon g theshorelin e 21-22/4/86 1nea rcam p

~~~~Table 10.25.Weigh t (g)an dbiometrica ldat a (mm)o fWillo wWarbler s captured inmistnet snea rth ecam p~~~~

~~~~date weight wing sex age fatscor e~~~~

12/3/85 10.3 66 4 31/3/85 7.2 63 0 1/4/85 6.2 62 ad. 0 1/4/85 6.8 62 ad. 1 3/4/85 7.3 64 ad. 1 3/4/85 8.1 71 ad. 3 3/4/85 8.7 63 ad. 4 3/4/85 7.2 68 ad. 0 3/4/85 9.5 70 ad. 3 4/4/85 8.3 64 2nd c.y. 3 4/4/85 7.6 63 ad. 2

187 4/4/85 7.1 64 ad. 0 4/4/85 9.8 65 ad. 4 4/4/85 8.8 61 ad. 4 4/4/85 9.3 68 ad. 2 4/4/85 10.5 65 ad. 0 4/4/85 9.7 70 2nd c.y. 4 4/4/85 8.5 65 ad. 3 5/4/85 6.8 64 female ad. 0 6/4/85 5.9 68 ad. 0 6/4/85 70 male ad. 0 14/3/86 8.2 69 3 15/3/86 7.5 72 ad. 0 15/3/86 9.4 68 ad. 0 20/3/86 12.3 67 ad. 5 21/3/86 7.3 68 ad. 0 21/3/86 6.6 69 ad. 0 21/3/86 7.3 69 ad. 0 22/3/86 6.8 71 ad. 0 22/3/86 6.8 68 ad. 0 22/3/86 7.9 68 ad. 3 23/3/86 6.2 63 0 23/3/86 6.6 70 ad. 0 24/3/86 6.9 62 0 26/3/86 7.0 70 ad. 0 29/3/86 7.2 71 ad. 0 30/3/86 6.4 68 ad. 0 30/3/86 7.4 69 ad. 0 30/3/86 6.1 71 ad. 0 31/3/86 7.1 69 ad. 0 2/4/86 6.1 70 ad. 0 3/4/86 6.3 63 ad. 0

Muscicapa striata SpottedFlycatche r Gobe-mouchesgri s Wintering inrathe rlarg enumbers ,mainl yi nth eS par to f thecountry . Passage fromAugust-Octobe r andApril-Ma y (Lamarche 1987). 11/4/86 1Ioui k

188 Ficedulahypoleuc a PiedFlycatche r Gobe-mouchesnoi r Wintering inrathe r smallnumber s inth eS par to fth ecountry .Muc hmor e numerousdurin gpassage ,mainl y fromAugust-Novembe r and inApri l (Lamarche 1987). 6/4/85 1mal eBai ed'Aouatif ,sit e6

~~~~Table 10.26.Weigh t (g)an dbiometrica ldat a (mm)o fa Pie dFlycatche r captured inmistnet snea r thecam p~~~~

~~~~date weight wing sex age fatscor e~~~~

~~~~15/4/85 8.2 80 male 2ndc.y. ? 0~~~~

Laniusexcubito r GreatGre yShrik e Piegrièch egris e Threesubspecie sma yb eencountere d inMauritania ,L.e .elegan san dL.e . leucopygosbein g themos tnumerous .Al lsubspecie sar ebreedin g inth e countrya swell ."Elegans "i smainl y tob efoun d inth eN part ,thoughou t theyear ,an dma yb esee no npassag e fromAugust-Novembe ran d February-April."Leucopygos "i sa rathe r commonresiden t breedingbir d fromth eS par to fth ecountry ,thoug hsom eN- Smovement shav ebee n recorded.Th estatu so f"dodsoni "stil li ssomewha t obscure.Possibl yi t isa rar ebreedin g bird fromth eAdra rregio ni nth ecentra lpar to fth e country (Lamarche 1987).Observation so f the 1985/86expedition s probably refer to"elegans" .Altenbur g etal .(1982 )observe d 1Grea tGre yShrik e inNouadhibo u inJanuar y1980 . 4/4/85 1i ngarde nNouadhibo u 22/1/86 1singin g gardenNouadhibou ; 1L aCherka ,Nouadhibo u 4/2/86 1cit ycentr eNouadhibo u 20/4/86 1betwee nSerin ian dTivid e

Laniussenato r Woodchat Shrike Piegrièch eà têt erouss e A rathercommo nwinterin g guest,occurrin gnea rwetland si nth eS par to f thecountry .Passag e fromJuly-Octobe r andMarch-Jun e (Lamarche 1987). 31/3/85 1Ebel kAiznai ;1 nea rcam p 1/4/85 1ad .mal eNiroum i 2/4/85 2Ebel kAizna i 3/4/85 1Ioui k

189 4/4/85 +nea r camp;2 i ngarde nNouadhibo u 5/4/85 +nea rcamp ;3 Bai ed'Aouatif ,sit e 6;2 o nairspri pW par tBai e d'Aouatif.On emal e catching smallFiddle rCrab s (less than 1cm )alon g theshorelin e 6/4/85 1o nairstri pW par tBai ed'Aouati f 11/4/85 1Ioui k 2/3/86 oldcorps e foundTanoudert ,win g 89m m 24/3/86 1Nai rmigratin gN E 16-17/4/86 1nea rcam p

~~~~Table 10.27.Weigh t (g)an dbiometrica ldat a (mm)o fWoodcha t Shrikes captured inmistnet snea rth ecam p date weight wing sex age fatscor e~~~~

~~~~4/4/85 293 94 male 2nd c.y. 0 4/4/85 253 95 female ad. 0 4/4/85 237 95 male 2nd c.y. 0 4/4/85 227 92 male 2ndc.y . 0 5/4/85 195 90 female ad. 0~~~~

Corvus raonedula Jackdaw Choucasde stour s Onlyon eobservatio n (25/10/85)fro mNouadhibo u (Lamarche 1987). 10/3/852 L aCherka ,Nouadhibo u 16/3/852 L aCherka ,Nouadhibo u 5/5/85 2L aCherka ,Nouadhibo u 3/2/86 5L aCherka ,Nouadhibo u

Corvusruficolli s Brown-necked Raven Corbeaubru n Commonbreedin g bird inth eN par to fth ecountry ,N o fth e 17thdegre e oflatitude ,frequentin gal lkind so fhabitat s (Lamarche 1987).Altenbur g etal .(1982 )observe d 5-10 individuals inNouadhibo u inJanuar y 1980an d somesingl e individualsbetwee nNouadhibo uan d Iouikdurin g the198 0 expedition. 10/3/852 Nouadhibo u 13/3/85 1Ca pBlan c 15/3/85 1lagoo nN airpor tNouadhibou ;5 alon g thebeac hN Nouadhibo u

190 14/4/855 Cham i 28/4/85 1nea rcam p 1/5/85 4N Epar t Iled'Argui n 3-4/5/852- 4L aCherka ,Nouadhibo u 5/5/85 2nea r Sabahhotel ,Nouadhibou ;2 L aCherka ,Nouadhibo u 20/2/86 1nea rcam p 25/2/86 1Aouguï t 2/3/86 6betwee nTanouder tan dBai ed eLévrie r 13-14/3/862 Bai ed'Aouatif ,sit e 1,watchin gFiddle rCra bburrow s 25/4/863 Il ed'Argui n

Passer simplex Desert Sparrow Moineaublan c Smallnumber sar efoun da sa breedin gbir d inth eN par to fth ecountr y (Lamarche 1987). 14/4/85 12Cham i 2/3/8610-1 5Acaci awood sN Tanouder t 7/3/868 amon gwhic h 3males ,nea rcam p 13/3/86 1i ncam p 21/3/86pai rnea rcam p 23/4/896 12nea rcam p

Passerluteu s SudanGolde nSparro w Moineaudor é Commonbreedin gbird ,mainl ybetwee nth eSénéga lrive ran d the18t h degreeo flatitude ,gettin grare rN o fthi s latitude (Lamarche 1987). Altenburge tal .(1982 )observe dhundred s inCansad oi nMarc h1980 . 18/3/85+ +Cansad o

Carduelischlori s Greenfinch Verdier Rarevisito r toMauritania ,onl yfe wsighting sfro mNouadhibo uan d Nouakchott (Lamarche 1987). 22-25/1/864 garde nSaba hhotel ,Nouadhibo u 2/3/86 5garde n Sabahhotel ,Nouadhibo u

Rhodopechysgithagene a SaharaTrumpete r Bullfinch Bouvreilgithagin e Rathercommo nan dwidesprea d asa breedin g bird throughout thecountry , butonl yoccurrin g inplace swher e freshwate ri savailabl e (Lamarche 1987). 22/3/86 1imm .mal enea rcam p

101 Emberizahortulan a Ortolanbuntin g Bruantortola n A frequently observed migrant,occurrin g inver ysmal lnumber sfro m September-November and inApri l (Lamarche 1987). 6/4/85 1mal eo nth ebeac hnea rcam p

~~~~10.3 Listo fobserve dmamma l species~~~~

Jaculus jaculus LesserEgyptia nGerbo a 30/3-2/4/85 1i ncam p 21/4/85 1nea rkitche nten t 8-24/2/861 i nkitche nten t 2/3/86 1i nten to fgenera lcoordinator ,eatin gpeanut san draisin s 13-15/3/86 1i nlaborator yten t 28/3/86 1capture d inkitche nten t 2-10/4/86 1i nlaborator yten t 14-23/4/863 i nsevera lplace si nth ecam p 16/4/86th efirs tjuvenile !

Merionescrassu s Jird 11/3/86 1(probabl y thisspecies )capture d infoo d storage tent,dye dan d released inth edune sfa rfro m thecam p 23/3/86dye d individual recaptured closet oth efoo d storagetent ,kep t ina cag eafterward s and released on23/4/8 6

~~~~Rattusnorvegicu s BrownRa t Surmulot 26/4/86 1harbou rNouadhibo u~~~~

~~~~WesternGroun d Squirrel Xeruserythropu s 26/2-24/4/86den s inth elo wdune sclos et oth ewater sedge ,nea rcam pa s wella si nEbel kAiznai ,occasionall ysee n~~~~

~~~~Canisaureu s CommonJacka l Chacalcommu n 23/3-25/4/85No wan d thensee no rhear d inth esurrounding s of thecam p 31/3/85 1Ebel kAizna i 24/3/85 1Tivid e 1/4/85 1Niroum i~~~~

192 6/4/85 1Ebel kAizna i 7/4/85 1Ca pTafari t 17/4/852 Ebel kAizna i 25/4/85 1Ebel kAizna i 12/2-24/4/86see no rhear d very frequently ino rclos e toth ecam p 12/2/86 2o ntida lflat sN Wpar tBai ed'Argui n 24/2/86trace sfoun da tFou mA lTriqu e 25/2/862 N Wpar tBai ed'Argui n 5/3/86 1feedin galon g theedg eo fth etida lflat sN Wpar tBai e d'Arguin 20/3/86 1pist eTeichot-Iouik ,clos et oSerin i 23-26/3/86 1feedin ga tnigh t Baied'Arguin ,sit e1 25/3/86de nfoun dEbel kAizna iwit hsmal lan d large tracesnearb y 1/4/86trace s foundSerin i 2/4/86trace sfoun dGiben e 3/4/86man y tracesfoun dTidr a 6/4/861 a t 12m distanc efro mobserver ,N Wpar tBai e d'Aouatif 9/4/86man ytrace sa swel la sden sfoun dTidr a 12/4/86 1W par tBai ed'Arguin ; 1Ebel kAizna i 13/4/86trace sfoun da tTidr aan dNiroum i 16/4/86 1followin g thewater sedg enea r thecamp ;1 Ebel kAizna i 17/4/86 1Bai ed'Arguin ,sit e3 walkin g indirectio nEbel kAizna i 20/4/86 1sleepin gTivid e 21/4/86 1N Wpar tBai ed'Argui n 24/4/86 1Ebel kAizna i

~~~~Felissylvestri ssard a Africanwil dca t Chat sauvage d'Afrique 19/4/85 1clos et oth emis tnet sEbel kAizna i 1/5/85 1H e d'Arguin~~~~

~~~~Gazelladorca s DorcasGazell e Gazelledorca s 25/2/86trace sfoun dTivid e 13/4/86 1mal ean d 1femal eTivid e 20/4/862 male s found dead So fTivid e~~~~

~~Tursiops truncatus BottlenoseDolphi n GrandDauphi n 20/3/85 20-30durin g crossing Baied eLévrie r 2/5/85 10-20durin g crossing Baied eLévrie r 5/2/86 someten sdurin gcrossin g Baied eLévrie r~~

,.93 2/3/86 1i nchanne lnex t toth ecam p 4/3/86 1i nchanne lnex t toth ecam p 18/3/86 1i nchanne lnex t toth ecam p 18/3/86 1foun ddea dTivide ,measurin g 299cm ,4 3c mfro meye-breathin g hole, 22teet hi nuppe rja wan d 21i nlowe rja w 4/4/86 1N EAre l 9/4/86 1Are l 13/4/86 1betwee nNai ran dTidr a 24/4/86 10-20are aaroun d CapTafarit ,5 H e d'Arguin 25/4/865 Bai ed eLévrie r

Sousa teuszi CamerunRive rDolphi n DauphinGuiné e 5/4/85 1i nth echanne lnex tt oth ecam p 30/3/85 1lande da t Iouik,capture d bySenegales efishermen ,lengt h26 9 cm,3 0teet hi nuppe ran d 28i nlowe r jaw(man ymor emeasure s taken) 1/4/85 1Are l 26/4/85 1i nth echanne lnex t toth ecam p 8-9/2/861- 2centra lpar tBai ed'Argui n 15/2/86 10-15passin g twicei nchanne lnex t toth ecamp ,swimmin gu pan d down 25/2/86 1i nchanne lnex t toth ecam p 3/3/86 1i nchanne lnex t toth ecam p 15/3/86 1i nchanne lnex t toth ecam p 17/3/86 1S o fIoui k 20/3/86 1i nchanne lnex t toth ecamp ;2 1nea rKiji ,swimmin g inN W direction 22/3/86 2i nchanne lnex t toth ecam p 24/3/8620-3 0N WKij i 25/3/86 1beache dReguïba ,lengt h28 2cm ,tai lwidt h 59cm ,2 9teet hi n upperan d 28i nlowe rja w 2/4/86 1Tivide ;1 Giben e 4/4/86 1-2N Niroum i 6/4/86 1betwee nTimy ean dTenvaddi r 8/4/86 5-10N EAre l 9/4/86 3Arel ; 1foun ddea d (forsevera lmonths )N par tTidra ,lengh t 219cm ,tai lwidt h5 6cm ,3 0teet hi nuppe ran d 28i nlowe rja w 11/4/86 1N WArel ;5 E Are l 13/4/862 W Are l

~~~~194 17/4/862 W Nai r 17/4/86 10nea rNai r swimming indirectio nAre l 19/4/86 1i nchanne lnex t toth ecam p~~~~

~~~~195 XI. TXME BUDGET OF WADERS~~~~

Anne-MarieBlomer tan dRoelo fHupke s 11.1Introductio n Beforewader swinterin go nth eBan cd'Argui nca nmigrat e tothei r northernbreedin ggrounds ,the yhav et oincreas ei nweight .Th eextr a energyca nb egaine d inthre eways : 1. Increasei ntota lforagin gtime . 2. Increasei nth eintak erat edurin gforaging . 3. Decreasei nth eoveral lexpenditur e ofenergy .

Iti shar d toimagin ea wa yi nwhic h thewader scoul d achieve thelas t possibility.Ther ear etw oroute st oth esecon d option.Eithe r thewader s workharde r toobtai nmor efoo d peruni t feeding time,a sshow nfo r oystercatcherwhe nfeedin g timewa sexperimentall y limited (Swennene t al.,i nprep.) ,o rth eavailabilit y of thefoo dincrease s inth ecours e of theseaso n (chapter 14).Her ew einvestigat e thepossibilit y thatth e wadersincreas e thetim espen t onforaging .

11.2Method s In198 5a pilo t studywa sundertake no nth emudfla t justopposit eth e campsite .A hid ewa serecte d on2 m o fscaffolding .Fiv esite smeasurin g 2 50b y5 0m anda s 'homogeneous'a spossibl ewer epegge d outwit hstakes . Observationswer ecarrie d outo n 1,8 , 14,2 2an d 26Apri ldurin g daylight.Ever yhal fhou ral lbird sfeedin gi nth esite swer ecounte dan d theiractivit yscore da sforaging ,sleepin go rpreening .Whe ntim e allowed thedat awer esupplemente d byrecordin g theactivit yo fa sman y birdsa spossibl eoutsid e thestud yarea .Fo rspecie swit ha wel ldefine d

196 summerplumag ei twa snote dho wfa rbod ymoul tha dprogressed . In198 6tw ohide swer eerecte d toth enort ho fth ecam psite .Th e firstoverlooke d amarke d areao f5 ha .Fro m 14Februar y to2 1Apri l observations tookplac ealmos tdaily ,followin g thesam emethodolog ya s in1985 .Th eothe rhid ewa soccupie d oncea wee kdurin g twoconsecutiv e low-tideperiods .On ewee ka complet edaytim elow-wate rperio dwa s followed bya complet enighttim elow-wate rperiod ,whil e theothe rwee ka halflight ,hal fdar kperio dwa sfollowe d bya hal fdark ,hal fligh t period.I ndaytim ea nare ao f6. 7 hawa scovered ,compare d toa nare ao f 2.5h adurin gth enight ,du et oth elimite d visualrang eo fth einfrare d night-scope.

~~~~FEEDING ACTIVITY, % loo~~~~

~~~~NEAP SPRtklft 16 TO 2H 2S °C~~~~

Figure 11.1. £Averag efeedin gactivit yo fDunli ndurin gnea pan dsprin g tidesan dintermediat e tidesi nFebruar yan dApri l 1986;b _Averag e feedingactivit yo fDunli na tdifferen t temperaturesgive napar tfo r Februaryan dApril .

11.3 Resultsan dconclusion s Daytimefeedin gactivitie swer ehig hi n 1985an d 1986an dcomparabl et o January 1980(Altenbur g etal . 1982).Wader si nmoul t spentmor etim eo n feeding thanindividual s inwinte rplumage .Thi scoul d bedu et oth efac t thatman y juvenilesneithe rmoul t tosumme rplumag eno rbuil d uplarg e fatreserve sfo rmigration ,o rd os orathe rlat ei nth eseaso n (chapter 9). Largeflock so fpreenin gan d sleepingbird swer esee noutsid eth e countingarea sdurin gnea ptide si nFebruar yan dMarch :henc e thefeedin g activitywa smuc hlowe ro nnea ptide scompare d toothe r tidesi nth esam e period,th eabsenc eo fsuc hflock si nApri l suggestsa nincreas ei n

197 overallfeedin g time (Fig. 11.1a). Increased feedingactivit y inth e course ofth eseaso nwa sals o suggested bya nincrease d densityo fwader s inth ecountin garea . Notal lwader spresen t indaytim eshowe d upa tnight .Th epresenc eo f somespecie swa sclosel ycorrelate dwit h theintensit yo fmoonlight . During thenigh tfeedin gactivit ywa salway sclos et o 100%.However ,th e densityo ffeedin gbird sincrease d notablyi nth ecours eo f theseaso n (Fig. 11.2).Probably ,th eincreas ei nnighttim e feedingcontribute dmor e toth eincreas ei noveral lfeedin g timetha nth esligh t increasei n daytimefeeding . Onho tday sfeedin gactivit ywa slowered ,bu tthi seffec tdisappear s inth ecours eo fth eseaso n (Fig. 11.1b). Theoretically itshoul db epossibl e tocombin e thedat ao ngros s energyintak e (chapter 13an d 14)an d thedat ao nextr aenerg yneede dt o gainweigh t (chapter 12)t ocalculat ewhethe r theweigh t increasei n spring (appendix)correspond s toth eobserve d increasei nforagin gtime . As thedat astands ,ther ear eto oman ycomplication s tomak eth e calculationfeasible .

~~~~198 X 2 WADER ENERGETICS~~~~

MarcelKlaasse n 12.1Hea t stresso nth eroos t During the 1986-expeditionth epossibl e loado fhea tstres so nroostin g waderswa sinvestigated .Experiment swit ha Bar-taile d Godwitmoun tan d behaviouralobservation so nBar-taile dGodwits ,Dunlin san dKentis h Plovers,wer econducte d atth ehig hwate rroosts .Th emoun texperiment s showed thatlayin gbird sencounte rhighe renvironmenta l temperaturestha n standingbirds .Hea tstres scanno t bea nacut eproble mo nth ehig hwate r roostsa sman ybird swer efoun d laying,o rstandin g onon ele gwit h tucked bills.Th efindin g thatroostin g birdsar eno t suffering fromhea t stress,canno t implicitly beextrapolate d toforagin gwaders .

~~~~199 MarcelKlaasse n& Brun oJ .En s~~~~

12.2I ssal t stressa proble m forwader swinterin g onth eBan cd'Arguin ? Manywade rspecie shav et odea lwit hgrea tenvironmenta lchange sdurin g theirannua lcycle .The ybree d inth earcti can d sub-arcticwhil ethe y spend thewinte runde r thetropica lsun .Fo rman yo fthe mi ti sals oth e timeo fth eyea ri nwhic h theyar ecompletel y restricted tosal twater . Thesal tload supo nth ewader sma ypossibl y limit theirenerg y expenditure.A possibl econsequenc eo fsuc ha limit ,woul d bea reduce d speedo ffoo d gatheringan dconsequen t reductioni nth erat eo fweigh t gainfo rmigration .Hea t stressedbird snee d increasingamount so fwate r forevaporativ ehea t loss.I ti stherefor econceivabl e thati nwar man d saltenvironment s thecombinatio no f saltan dhea tload sincreasingl y stressth ebirds . During the 1986-expeditionth epossibl e loado fsal tupo nsom e winteringwaders ,wa sinvestigated .Knot san dSanderling swer euse di n cageexperiment s inwhic hwate ran d foodconsumptio nwer emeasure dunde r different salt regimes.Foo dconsumptio ndecrease d andwate rconsumptio n increased afterchangin g thewate r provided fromfres ht osalt . Experiments inwhic h saltwate rwa sprovide d toKnot sove ra longe rtim e scalereveale d thatKnot shav ea ver yhig htoleranc ean dcapabilit yo f adaptiont osal twater .I ti scalculate d thata ta maximu mfoo dintak e levelo fisotoni cpre yitems ,th eKno tma yno thav egrea tdifficultie s with thesal t load.Th esituatio nma yb ewholl ydifferen t forspecie s whichar ephysiologicall y lesswel ladapted ,lik eth eSanderling . Evaporativecoolin g inhea tstresse d birdsmigh t increasesal tstress .A negativecorrelatio nbetwee nambien t temperaturean dfoo dconsumptio nwa s foundwhe nsal twate rwa sprovided .However ,thi srelatio nfoun di s probablydu e toth eincrease d salinityo f thedrinkin gwate ra thig h ambient temperatures,an dno tt oincrease dwate rdeman d forevaporativ e cooling.Th ebird sals odi dno tavoi d theextr aendogenou shea t productionassociate dwit hfoo d intakedurin g thewarmes tpart so fth e day.Nevertheless ,fiel d observations suggest somehea tand/o rsal t stressi nforagin gwader sa tday swit hhig hambien ttemperatures . However,durin g fatdeposition ,necessitatin g ahighe rforagin g intensity,th emaximu m temperaturesa tth eBan cd'Argui nar egenerall y moderate.

200 MarcelKlaasse n& Brun oJ .En s 12.3 Energeticcos to fweigh tgai n Toevaluat e theexten t towhic h thepremigrator yweigh tgai nform sa heavyburde nfo rth ewader spreparin g tomigrat efro m theBan cd'Argui n inspring ,cag eexperiment swer econducte d tomeasur e theextr afoo d needed togai nweight .I n198 5seve nTurnstone swer ekep ti ncaptivit y from 30Marc ht o3 0April .I n198 6twelv eKnot san d fiveSanderling swer e kepti ncaptivit y from7 Marc ht o2 2April .Al lbird swer eprovide dwit h freshwate ra dlibitu man da commercia lfeeder .A tregula r intervals (varying from 2t o5 day sdependin g onth especies )al lbird swer e weighed and foodconsumptio nove rth einterva lwa smeasured .Thes edat a allowed aplo t relatingdail yfoo dconsumptio n todail yweigh t change.A s

~~~~CVULY FOODCONSUMPTION ,G /BIRD .DA Y~~~~

~~~~•8 -6 -^ -2 O 2 *4 6 DAILY WEIÄWT CMAMGE,~~~~

Figure 12.3.1 Daily food consumption (gram pelsifood per Turnstone per day)a s a function of daily weight change (gram body weight per Turnstone per day).Close d dots refer togrou p means,an d the open dots todat a points for individuals when food was provided ad libitum. The open square reports the average weight loss when the food was taken away for a day.

201 anexampl e thedat afo rTurnstone sar eshow ni nfigur e 12.3.1.Th e intercept of thelin eca nb einterprete d asth eenerg yneede d tosta y alive inth ecag e (MMR=MaintenanceMetaboli c Rate),wherea s theslop e presentsa measur eo f thefoo dneede d togai n 1gra mi nweight .T o convert thesegros sintak e ratesint oassimilate d energy,assimilatio n efficienceshav et ob eknown ,whic hwer eonl ymeasure d in 1986usin g chromiumoxid ea sa marke ri nth efoo dan dexcret a (Table 12.3.1). Assimilation efficiences reported fromstudie so nwader si ntemperat e climateso nth esam edie ta suse d inth eTurnston eexperiment s tendt o varyaroun d 85%(Kerste n& Piersm a 1987).Estimate sfo rth ecos to f gainingweigh tunde r temperate conditionsrang ebetwee n2 5an d 51k Jpe r grambod yweigh t (calculated fromtabl e 4i nKerste n& Piersm a (1987). Theestimate so fou rexperiment sar eo fth esam emagnitud e (Table 12.3.1).Cos to fgainin gweigh t ishighes t forTurnstones .The ywer eals o theonl y species that reached departureweight sdurin gexperiments .A t leasti nKnot srapi daccumulatio no ffa t (themos tcostl yi nterm so f energyneede d togai n 1gra mi nbod yweight )seem st ostar tonl ybeyon da specificbod yweigh tbefor ewhic honl ywater-ric h (70%)protei ni sstore d (chapter 8). Henceth einser tdat ao nTurnston eprobabl yprovid eth ebes t estimatefo rth ecos to fgainin gweight .Th eBan cd'Argui nmayb ea goo d place toaccumulat e fatreserve sfo rmigratio ndu et oth elo wenerg y costsfo rthermoregulation ,althoug hsal tstres smigh tcaus eproblem s (seechapte r 12.2.).Clearly ,mor edat aar eneede do nth erelationshi p betweenassimilatio nefficienc y andambien t temperaturean dexperiment s shouldb ecarrie dou tfo rmor enatura lcondition s (saltwate ran dnatura l food).

Table 12.3.1. Assimilationefficience s (notmeasure d inTurnstones :tw o assumedvalue sar epresented) ,mea nmetaboli crate s (MMRi nk Jpe rbir d perday )an denergeti ccos to fweigh tgai n(e wi nk Jpe rgra mbod y weight)fo rcaptiv eSanderlings ,Knot san dTurnstones .

~~~~Assimilation MMR efficiences~~~~

~~~~Sanderling 0.62 (n=1 ) 89 21.5 (r=0.921,n=15 ) Knot 0.70(n=12 ) 181 25.6 (r=0.869,n=76 ) Turnstone 0.85 ( -) 235 40.7 (r=0.996,n =7 )~~~~

~~~~202 13. FORAGING OYSTERCATCHERS ON THE~~~~

~~~~BANC E> * ARGUIN~~~~

~~~~C. Swennen~~~~

Alldat afo rthi sstud ywer ecollecte d from 7t o2 8Februar y 1986.Flock s ofOystercatcher sHaematopu so .ostralegu swer eonl ysee nforagin go n bedso fth eBlood yCockl eAnadar asenili s thatwer epresen t onintertida l flatsi nan daroun d theBai ed'Aouati f (Bancd'Arguin) .A fe wsingl e birds,tha twer eprobabl yill ,wer eobserve da tothe rsite s (beacho f Iouik,harbou ro fNouadhibou) . Althoughsom eOystercatcher s flewfro m theirhig hwate r roostst oth e emerging tidalflat sa tth esam etim ea sth eothe rwaders ,th emajorit y departed lateri nth etida lcycle .I ncontras twit hwha twa sobserve d in most otherwader spresent ,th eOystercatche r shown ointensifie d feeding inth ebeginnin gan da t theen do fth elo wtid eperiod . Detailed feeding observationswer econducte d froma nelevate d hideo n anintertida l flata t theBai ed'Aouatif .I tcoul db eestablishe d that adultsfe do nA .senilis .Juvenile sappeare d tob eles sspecialize dan d tookothe rpre y speciesa swell . Oystercatchers obviously locatedmos t ofthei rpre yb yey ewhil e walking slowly.The yalway sopene d thebivalv eb ystabbing .Stabbin g movements seemed tob edirecte d toth efrontal-ventra l side,whic hi s ratherdee pi nth esediment .Undisturbe d handling timeswer eabou t 3.5 mino naverage .Th efirs tpar t ofa handlin gepisod efro mhavin glocate d thepre yt oswallowin g thefirs tparce lo fflesh ,too ko naverag e 69sec , and thelas tpar t 143sec .Th emaximu mundisturbe d handling timelaste d 570se c (9.5min) . Itdi dno tbecom eclea rho wth ebird swer eabl et o openshell swithou t damaging their bill.Th ehandlin g couldno tb e imitated byth eautho rwit hlivin gindividual so fA .senilis .Th emeta l

203 bill-modelwa salway s trapped between thever ysoli dvalve so fth e animalswithi n 20se cfro mth emomen t thatth efles hwa stouche d between somewhatgapin gvalves . Onaverag e theOystercatcher s opened 1.6A .senili spe rhour .Thi s represents 5.3g ash-fre edr yweigh t (ADW)o fflesh .Becaus eo f kleptoparasitism,th erea lconsumptio nwa sestimate d atonl y 2.9g AD Wo f fleshpe rhour .N odifference swer efoun dbetwee nnumbe ro fcockle s opened perhou rdurin g lowwate r inda ytim ean dlo wwate rdurin gnight s withmoonlight .Tota l realconsumptio n couldb eestimate d at 19.2g AD W offles hpe rlo wwate rperio da tdaytime . Themai nkleptoparasite swere :Lesse r Black-backed GullsLaru sfuscu s and Slender-billed GullsLaru sgenei .Usuall yafte r thebivalv eha dbee n abandoned by theOystercatche r ora kleptoparasite ,a Turnston eArenari a interpres ora Curle wSandpipe rCalidri sferrugine acam et oinspec tth e areafo rpiece s thatmigh thav ebee nlos tb yth elarge rbirds .Durin g diurnallo wwate rsom eGre yPlove rPluviali ssquatarol abehave da s Turnstones,bein g satelliteso fsom efeedin gOystercatchers ,withou t reallykleptoparasitizin g (i.e.overtakin g thewhol eprey) .Durin gth e night,however ,Gre yPlover sbehave d successfully askleptoparasites .Th e gullswer eals opresen to nth efla ta tnight ,bu tremaine d rather inactive. Themea ndensit yo fforagin gOystercatcher s onth estudie d flatwa s about 4.9 perha .Blood yCockl edensitie svarie dbetwee n5 an d 48cockle s o perm ,wit hshell svaryin gi nlengt hbetwee n5 0an d 91mm .Th eemptie d shellso ffreshl yeate ncockle swer eeas yt olocate .I tappeare d thatth e Oystercatcherdi dno tselec t forshel lsiz ewhe nfeeding . Thegull san d theothe rwader swer eunabl e toope na nA .senili sb y themselves.Eve nwhe na nOystercatche rha dopene da nAnadara ,the y usuallyha d towai tunti lth eOystercatche rha d takena piec eo ffles hi n itsbill .Th enarro w slitbetwee nth evalve scoul dno tb eopene dwid ean d therefore thebill so fgull san d smallwader swer eusuall yunabl et o reach thefles ho fth emollusc .Th ecockle seate nb yth eOystercatcher s inMauritani amus tb eth elarges tpre ytake nb yan ywade ri nth eworld : thetota lfres hweigh t ofth ebivalve svarie d between 150an d 509g .Th e largestshell sha dabou t thesam eweigh ta sth ebirds !Du et oth eheav y kleptoparasitism,Oystercatcher sha d toope nabou t twicea smuc hshell s thanthe yneede d forthei row nfood .

~~~~204 14. FEEDING BEHAVIOUR OF WHIMBREL AND~~~~

~~~~ANTI-PREDATO R BEHAVIOUR OF ITS MAIN PREY, IHE FIDDLER CRAB UCA IANGERI~~~~

LeoZwart san dSjoer dDirkse n 14.1 Introduction Theprimar yai mo fthi spar to fth eprojec twa s toarriv ea ta nestimat e ofth edail ygros senerg yintak eo fa tleas ton ewade rspecie sunde rth e tropicalcondition so f theBan cd'Arguin .Throug hextrapolatio nth e resultcoul d thenb euse d toestimat e thefoo dconsumptio n ofothe rwade r species.A pilo t studyi n198 5reveale d thatWhimbre lpreyin go nfiddle r crabsar eno tonl ywel lsuite d tomak efiel destimate so ffoo dintake , butals oextremel ywel l suited tomak ea muc hmor e fundamental investigationo fth erelationshi pbetwee npredato ran dprey .

14.2 Methods Acontinuou srecor d of thefeedin gbehaviou ro fon eWhimbre lwa smad e (whenpossibl ethroughou t thewhol e tidalcycle )fro ma hid eo nto po f5 m ofscaffoldin g located inth eNW-corne r ofth eBai ed'Aouatif .A tota l of20 0hour so fobservation swer ecollecte d onthre eindividual s defendinga territor y onth ebeac han dadjacen tmudd y Zosteraflats . Thesurfac eactivit yo fUc awa smeasure d inthre eways : 2 - regular countswit ha telescop eo fUc apresen t in1 3plot so f4 m . 2 countso fburrow s in7 6plot so f 1o r4 m ;th eburro wdiameter swer e measured toestimat e thesiz efrequenc ydistributio n (Zwarts 1985). recording theactivit yo fUc awit ha fil man d photocamer amounte do n a tripod;picture swer emad ea t regular intervalsdurin g theentir e lowwate rperiod .

205 14.3 Preychoic eWhimbre l Whimbrelso nth eBan cd'Argui nselecte d threepre y species:Uca , 'Pilumnus'an dCallinecte s (allcrabs) .A totalo f93 4crab swer etake n by thethre e individuals studied:83.4 %Uca ,15.6 %'Pilumnus 'an d0.7 % Callinectes« Whimbrels fedo nth ebeac hi fUc awer epresen t there,bu tswitche d to theZoster aare a tosearc hfo r 'Pilumnus'i fn oo ronl ya fe wUc awer e found onth ebeach . SmallUc a wereignored ,eve nthoug h theywer ever ycommon .Mos tUc a takenha da carapa xwidt ho f 15-20mm .Th eselectio nfo ra larg epre ywa s less pronounced in 'Pilumnus':58 %o fthes epre yha da carapa xwidt ho f less than 10mm . Ucao f 15-20m mliv ei nburrow stha tar eto odee pfo ra probin g Whimbrel.Therefore ,al lUc awer e takenwhe npresen to nth esurfac eo r whenleavin g theirburrows .

14.4 Totalfoo dintak eWhimbre l Thedensit yo fUc ao nth esurfac eha da larg eeffec to nth efoo dintak e ofa Whimbrel .Th eintak eo nth ebeac hwa smaxima li fth eUc adensit ywa s highan dminima l ifmos tUc aremaine d inthei rburrow .Onl y thenth e Whimbrel switched toth eZoster aarea ,wher efoo d intakewa slo wtoo . WhenUc awer epresen to nth ebeac hth emaxima lfoo dintak ewa sno t limitedapparently ,b yth enumerica ldensit yo fUca .Afte reatin g 3-5 largecrabs ,th ebir dalway s tooka pause ,suggestin ga digestiv e bottleneck.Thu sth etota lfoo d intakemainl ydepende d onth epresenc eo r absence ofUc ao nth esurface . Thesurfac eactivit yo fUc aseeme d tob edetermine db y thefollowin g variables: - timewithi nth etida lcycle :n oUc awa seve robserve d outsideit s burrowsdurin g the5 hour saroun dhig hwater . - temperature:n oUc aappeare d onth esurfac ewhe nai r temperaturewa s 17°Co rless . -wate r levela tpreviou shig h tide.Th eeffec twa slimite d forth esmal l Ucalivin go nth elowe rpar to fth ebeach ,bu tver ypronounce d forth e largeUc ahavin g theirburrow shig hu po nth ebeach .Thes elarg eUc a appeared onth esurfac edurin g spring tidelo wwate rperiod sonly . Besideshig hwater ,al lcol dperiod s (thegreate rpar to fth enight s and earlymornings )an dnea ptide swer etime swhe nth eWhimbrel scoul d

206 obtainlittl e food.Despit ea larg evariatio ni nth efoo d intakefro mon e lowwate rperio d toth enext ,a gradua l increase fromFebruar y toApri l wasapparent .Thi swa sdu et otemperature s of 17C an d less,occurrin g lessofte nlat ei nth eseason .Th epremigrator yweigh t increaseo fth e Whimbrelma ythu sb eattribute d toth eeffec to f temperature onth e availability ofit smai nprey .

14.5Pre yavailabilit y Itwoul db eto osimpl e toequat e 'preyavailability 't o 'densityo fUc a onth esurface' .Specia lattentio nwa spai d therefore toth ewa yUc a minimize theris ko fbein g takenb ya bird : - howfa rd oforagin gUc amov efro mthei rsaf eburrows ? - what isit sburs t speedwhe ntakin gfligh t toit sburrows ?Th e positivecorrelatio nbetwee nburs tspee dan dtemperatur ema yexplai n whyUc ad ono tleav ethei rburrow sa tlo wtemperature . - atwha tdistance sfro ma napproachin g predatorstar tth eescape ? howlon gd oUc aremai ni nthei rburrow sfollowin ga disturbance ?

Whenth eescap ebehaviou ro fUc ai scompare d toth efeedin g capabilities ofWhimbre l (likeit smaxima l running speed)i ti sclea r thatWhimbre lhav et owor khar d tofin denoug hpre yi fth eUc aremai ni n theirburrowin g zone.Th esituatio ni scompletel y different ifth ecrab s leavethei rburrowin g zonei nver ylarg eherd st ofee delsewhere .Thi s occurred during 1t oA lo wwate rperiod spe rfortnight . Thust ounderstan d theavailabilit y ofUc aw emus tunderstan d their willingness totak erisks .I tremain st ob eshow ntha tUc aonl yaccep t high riskswhe npotentia lbenefit sar ehig htoo .

~~~~207 15. LIST OF MARINE PHANEROGAMS, MOLLUSCS,~~~~

~~~~POLYOHAETES AND CRUSTACEA OBSERVED~~~~

~~~~ALIVE AT THE BANC DfARGUIN IN 1985~~~~

~~~~AND/OR 1986~~~~

WimJ .Wolf f 15.1Aquati cphanerogam s Thefollowin g specieso faquati cphanerogam s (identifications Prof.Dr . C.de nHartog )wer eobserve d atth eBan cd'Argui ndurin gou rstudies : Zosteranoltii ; Cymodoceanodosa ; Halodulewrightii .

15.2Mollusc s Only speciesobserve d aliveo r recentlydea dhav ebee nliste dbelow . Nomenclature isi nmos tcase saccordin g toNordsiec k (1968, 1969),bu t thename suse d byNicklè s (1950)ar egive ni nbracket s ifdifferent . Thenumber sdenot eou rsamplin g sites (Fig.21.1) .

~~~~Jujubinus striatus (Linné)(Calliostom a striatum). Samples:52 ,10 9 Beach ofIoui k~~~~

~~~~Gibbulacande i (d'Orbigny)(Gibbul aumbilicalis ) Samples:68 ,151 ,170 .Nea rsamples :84 ,93 ,176 ,178 .~~~~

~~Monodonta lineata (daCosta )(Monodont a colubrina) Livingi nth etida lzon eo fth erock yshor eo fKiaone . Altenburg etal .(1982 )recor dMonodont a lineataan dM .cf .articulat a Lam.fro mKiaone .~~

~~~~Tricoliapullu s(Linné ) Samples:53 ,69 ,192 . Beacho fIoui k~~~~

~~~~Peringiaulva e (Pennant)(Hydrobi aulvae ) Samples: 11,31 ,49 ,69 ,90 ,115 ,126 ,152 ,154 ,187 ,194 ,226 . Beacho fIouik . Altenburg etal .(1982 )foun d thespecie snea rArel ,Ioui kan dKiji .~~~~

~~~~208 Cap Timiris~~~~

~~~~Fig. 21.1. Localities at the tidal flats where bentic fauna sampels were taken in 1986.~~~~

~~~~209 Mesallabreviali s (Lamarck)(Turritell a torulosa) Samples: 13,31 ,36 ,40 ,53 ,82 ,126 ,153 ,170 ,194 ,226 . Common ontida lflats .~~~~

~~~~Bittlumreticulatu m (daCosta ) Samples:28 ,69 ,148 ,18 5 Altenburg etal .(1982 )foun d Bittlumnea r Iouikan dArel .~~~~

~~~~Calyptraea chinensis (Linné) Samples:5 3 Beacho fIoui k~~~~

Crepidulaporcellan aLamarc k Samples:37 ,47 ,54 ,79 ,84 ,93 ,109 ,118 ,135 ,146 ,148 ,170 . Beach ofIouik . Commono nshell so fAnadar a senilisan d epibenthicgastropods .Altenbur g etal .(1982 )foun d thespecie snea r Iouikan dKij i (asC .goreensis )

~~~~Nacca fulminea (Gmelin)(Natic afulminea ) Baied'Aouatif ;Beac ho fIouik . Altenburg etal .(1982 )foun d thespecie sa t thebeac ho fIouik .~~~~

~~~~Murexcornutu sLinn é Inth emai nchanne lo fth eBai ed'Aouatif .~~~~

~~~~Columbella rustica (Linné) Samples:47 ,52 ,57 ,79 ,84 ,109 ,118 ,141 ,146 ,171 ,176 . Beacho fIouik .~~~~

~~~~Cantharus dorbignyi (Payraudeau)(Pisani a d'orbignyi) Samples: 118,140 ,141 ,148 .~~~~

~~~~Semifususmori o (Linné) Near samples69 ,185 ,200 .~~~~

~~~~Hiniamig a (Bruguière)(Nass amiga ) Samples:3 ,36 ,40 ,52 ,57 ,69 ,79 ,109 ,118 ,148 ,190 . Beacho fIoui k~~~~

~~~~210 Amyclina pfeifferi Philippi Samples: 13,27 ,93 ,126 ,226 . Beacho fIoui k Altenburg etal .(1982 )foun dA .pfeiffer inea rChikchitt ,Cheddi dan d SouthTidr a~~~~

~~~~Cymbiumcymbiu m (Linné) Altenburg etal .(1982 )recor d Cymbiumcymbiu m (Linné)nea rIoui kan d Nair. Weobserve d ita tsevera lplace s inth evicinit y ofIoui kan d inth eBai e d'Aouatif.~~~~

~~~~Persicula cingulata (Dillwyn) Samples: 37,9 0 Beacho fIoui k~~~~

~~~~Persiculachudeau iBava y Samples:28 ,10 9~~~~

~~Prunumamygdalu m (Kiener)(Marginell aamygdala ) Samples:14 ,27 ,28 ,31 ,79 ,146 ,151 ,159 ,170 ,185 ,192 . Beacho fIouik . Altenburg etal .(1982 )foun dPrunu mamygdalu mnea rChikchit t andCheddi d~~

~~~~Clavatula bimarginata (Lamarck) Samples:37 ,52 ,57 ,79 ,82 ,90 ,93 ,109 ,118 ,146 ,151 ,166 ,171 ,172 , 176. Beacho fIoui k Altenburg etal .(1982) :nea rChikchit t andSout hTidra .~~~~

Conuspapilionaceu s Bruguière (Conuspapilionaceu sHwass ) Near samples 84,93 ,175 ,176 ,185 . Altenburg etal .(1982 )recor d Conuspulche rpapilionaceu sHwas sfro mth e mudflatsnea rArel ,Iouik ,Kij ian d S.Tidr a

~~~~Conusgenuanu sHwas s Samples:26 ,52 ,118 ,135 ,146 ,17 0 Altenburg etal .(1982 )recor d apparently thesam especie sa sConu s~~~~

~~~~211 guinaicusHwas sfro m themudflat snea rArel ,Iouik ,Kij ian d Cheddid.~~~~

~~~~Bullariaadanson iPhilipp i Samples: 166,170 ,17 2 Beacho fIoui k~~~~

~~~~Hamineaelegan s Samples:11 8~~~~

~~~~Hamineaorblgnyan aFérussa c Samples: 11,28 ,36 ,89 ,135 ,178 ,191 . Beach ofIouik .Altenbur g etal .(1982 )recor dHamine acf .orblgnyan a frombetwee neelgras snea rChikchit tan d SouthTidra .~~~~

~~~~Cylichna grimaldiDautzenber g Beacho fIoui k~~~~

~~~~Dentaliumsenegalens eDautzenber g Beacho fIoui k~~~~

~~~~Nucula turgida (Winckworth) (Nuculanitida ) Samples:6 8 Beacho fIoui k~~~~

~~~~Areaafr aGmeli n Samples:6 ,14 3~~~~

Anadara senilis (Linné) Samples:6 ,11 ,17 ,19 ,26 ,32 ,36 ,47 ,54 ,81 ,135 .143 ,159 ,166 ,170 . Verycommo na t thenearshor e tidalflat so fth eBan cd'Arguin ,wher e Altenburg etal .(1982 )als ofoun d itplentiful .

~~~~Crenelladecussat adollfus iDautzenber g (Crenelladollfusi ) Samples:6 ,40 ,159 . Beacho fIoui k~~~~

~~~~Lingacolumbell a (Lamarck)(Phacoide sadanson i d'Orbigny) Beacho fIoui k~~~~

~~~~212 Altenburg etal .(1982 )foun dLing aadanson l (d'Orbigny)aliv enea rArel .~~~~

Loripeslacteu s (Linnè) Samples:3 ,14 ,17 ,19 ,26 ,27 ,28 ,31 ,33 ,36 ,37 ,40 ,47 ,50 ,52 ,53 , 57,59 ,69 ,79 ,81 ,82 ,89 ,90 ,93 ,109 ,118 ,135 ,141 ,143 ,145 ,146 , 147,148 ,151 ,154 ,166 ,170 ,171 ,172 ,176 ,178 ,190 ,191 ,192 . Verycommo ni nal l tidalflats .Als oAltenbur ge tal .(1982 )foun d this specieslivin ga tal lsite sapar t fromChikchitt .

~~~~Pythinamactroide sHanle y Samples:6~~~~

~~~~Cerastodermaedul e(Linné ) Samples:31 ,53 ,126 .~~~~

~~~~Dosinialupinu s (Poli) Samples:12 6 Beacho fIouik ?~~~~

~~~~Venusverrucos aLinn é Nearsamples :44 ,20 0~~~~

~~~~Tagelusangulatu s(Sowerby ) Baied'Aouatif ; Beacho fIouik . Altenburg etal .(1982 )mentio nT .angulatu sfro mth eBai ed'Aouatif ; freshlydea d specimensnea rIouik .~~~~

Abratenui s(Montagu ) Samples: 13,17 ,19 ,27 ,53 ,57 ,68 ,79 ,81 ,82 ,84 ,92 ,126 ,135 ,140 , 148, 152,154 ,166 ,171 ,176 ,178 ,190 ,192 ,196 ,226 . Commona tal lsite saccordin g toAltenbur g etal .(1982 )

~~~~Gastranamatado a (Gmelin) Baied'Aouatif ;recentl ydead .~~~~

~~~~Solenmarginatu s (Pennant) Beachd 'Ioui k~~~~

213 Aloides laticosta (Ed.Lamy ) Samples:6 ,159 . Other species recorded byAltenbur ge tal .(1982 )an dPiersm a &Molenbeek . (1982)are :Smaragdl aviridis ,Truncatell a subcyclindrica,Risso acf . membranacea,Terebr asenegalensis ,Strigatell a zebrina,Bursatell a leachi,Siphonari apectinata ,Solemy atogata ,an dDosini ahepatica , Of theseSmaragdia ,Truncatella ,Risso aan d Siphonaria originated from rockyshores ,a biotop ehardl yinvestigate d byus ,wherea s Solemyawa s found inth estomac ho fa fish .

~~~~15.3 Polychaetesan dOligochaete s~~~~

~~~~Eteone longa (Fabricius) Beacho fIoui k~~~~

~~~~Anaitidesmucos a (Oersted) Samples:3 6~~~~

~~~~Eumida sanguinea (Oersted) Samples:47 ,118 ,166 ,17 0~~~~

~~~~Typosyllisarmillari s(O.F .Müller ) Samples:3 ,6 ,26 ,59 ,69 ,143 ,150 ,159 ,191 ,192 ,194 ,225 ,22 6~~~~

~~~~Exogoneveruger a (Claparède) Samples:6 8~~~~

~~~~Perinereiscultrifer a(Grube ) Samples: 6, 14,33 ,36 ,37 ,44 ,47 ,53 ,73 ,81 ,90 ,93 ,118 ,135 ,191 , 194,196 ,200 ,22 6~~~~

~~~~Nereisfals a Samples:53 ,68 ,7 3~~~~

~~~~Nereiscaudat a (DelleChiaje ) Samples:44 ,49 ,50 ,52 ,54 ,90 ,135 ,170 ,196 ,22 6~~~~

~~~~214 Nereisspec . Samples: 13,14 ,26 ,27 ,36 ,37 ,90 ,140 ,146 ,151 ,154 ,159 ,170 ,17 5~~~~

~~~~Nephtysspec . Samples:3 2~~~~

~~~~Glyceraalb a (O.F.Müller ) Samples:28 ,18 5~~~~

~~~~Glycera rouxi (Audouin& Milne-Edwards ) Samples:28 ,69 ,15 1~~~~

~~~~Glycindenordmann i (Malmgren) Beacho fIoui k~~~~

~~~~Onuphiseremit a Samples:2 8~~~~

~~~~Diopatraneapolitan a Samples:3 ,6 , 11,17 ,31 ,36 ,73 ,79 ,90 ,135 ,143 ,145 ,150 ,153 ,159 , 175,191 ,192 ,194 ,200 ,22 6~~~~

~~~~Marphysasanguine a (Montagu) Samples:6 , 11,14 ,17 ,19 ,26 ,28 ,32 ,33 ,36 ,50 ,59 ,90 ,93 ,118 ,140 , 141,143 ,145 ,146 ,151 ,166 ,170 ,176 ,190 ,192 ,194 ,19 6~~~~

~~~~Nematonereisunicorni s Samples:6 ,7 3~~~~

~~~~Lumbrinerisspec . Samples:33 ,40 ,73 ,140 ,143 ,151 ,172 ,178 ,191 ,192 ,19 4~~~~

~~~~Arabellamutan s Samples:6 ,31 ,32 ,44 ,146 ,175 ,178 ,191 ,192 ,20 0~~~~

~~~~Drilonerisfilu m (Claparède) Samples:3~~~~

~~~~!15 Naineris laevigata Samples:3 ,6 , 11,14 ,17 ,26 ,28 ,36 ,43 ,47 ,54 ,59 ,65 ,69 ,81 ,82 , 84,90 ,93 ,118 ,135 ,140 ,143 ,145 ,153 ,166 ,170 ,171 ,175 ,176 ,178 , 185, 190,191 ,192 ,19 6~~~~

~~~~Scoloploscapensi s Samples:6 , 11,17 ,26 ,28 ,31 ,32 ,36 ,50 ,53 ,82 ,118 ,145 ,147 ,153 , 159,176 ,185 ,194 ,22 6~~~~

~~~~Scoloploschevallier l Samples:6 ,11 ,26 ,31 ,36 ,53 ,82 ,90 ,135 ,145 ,146 ,159 ,166 ,175 , 192,22 6~~~~

~~~~Polydoraantennat a (Claparède) Samples:6 ,26 ,27 ,49 ,68 ,140 ,22 6~~~~

~~~~Prlonospiomalmgren l (Claparède) Samples:2 8~~~~

~~~~Aricldeafauvel l Samples:6 ,36 ,73 ,79 ,90 ,153 ,17 5~~~~

~~~~Arlcidea longobranchlata Samples:73 ,89 ,18 5~~~~

~~~~Cirriformiatentaculat a (Montagu) Samples:3 ,26 ,32 ,47 ,49 ,57 ,59 ,69 ,79 ,81 ,109 ,140 ,143 ,145 ,171 , 172,176 ,185 ,192 ,22 6~~~~

~~~~Scolelepis squamata(Muller ) Samples:2 8~~~~

~~~~Tharyxmarlon l (Saint-Joseph) Samples:6 ,28 ,89 ,90 ,145 ,153 ,154 ,15 9~~~~

~~~~Armandiaintermedi a Samples:36 ,73 ,153 ,19 1~~~~

~~~~216 Capitellldaespec . Samples:1 7~~~~

~~~~Capitellacapitat a (Fabricius) Samples:3 ,6 , 13,26 ,27 ,31 ,32 ,49 ,53 ,68 ,79 ,81 ,90 ,109 ,115 ,118 , 124, 126,143 ,145 ,147 ,152 ,154 ,159 ,165 ,171 ,175 ,178 ,190 ,22 6~~~~

~~~~Heteromastusfiliformi s (Claparède) Samples:6 ,11 ,19 ,27 ,47 ,49 ,68 ,69 ,79 ,90 ,92 ,93 ,135 ,140 ,141 , 145,146 ,148 ,153 ,154 ,159 ,166 ,172 ,185 ,191 ,19 2~~~~

~~~~Arenicolidaespec . Samples:10 9~~~~

Euclymeneoersted i (Claparède) Samples:3 ,6 , 11,13 ,14 ,17 ,26 ,28 ,31 ,32 ,36 ,37 ,40 ,47 ,49 ,50 , 52,53 ,54 ,65 ,69 ,73 ,82 ,90 ,93 ,109 ,118 ,135 ,140 ,141 ,145 ,147 , 148,151 ,153 ,154 ,159 ,166 ,170 ,171 ,175 ,176 ,185 ,192 ,194 ,196 , 200,22 6

~~~~Petaloproctusterrlcol a Samples:6 ,11 ,13 ,14 ,17 ,32 ,36 ,40 ,47 ,65 ,73 ,82 ,90 ,140 ,143 , 145,146 ,159 ,191 ,192 ,194 ,196 ,20 0~~~~

~~~~Isoldawhydahaensl s Samples:2 8~~~~

~~~~PIstaspec .cf .crlstat a (O.F.Muller ) Samples:90 ,140 ,151 ,20 0~~~~

~~~~Terebellalapidarl a 11,36 ,59 ,65 ,82 ,90 ,153 ,154 ,194 ,196 ,20 0~~~~

~~~~Polycirrusaurantlacu s(Grube ) Samples:3 ,11 ,59 ,69 ,82 ,89 ,118 ,145 ,19 2~~~~

~~~~Hypslcomusspec . Samples: 11,36 ,14 3~~~~

~~~~217 Sabellidae spec. Beacho fIoui k~~~~

~~~~Bhawaniagoode i Samples: 159~~~~

~~~~Polynolnae spec. Samples:5 9~~~~

~~~~Jasmlnelraelegan s (Saint-Joseph) Samples: 79,15 3~~~~

~~~~Fabricla sabella (Ehrenberg) Samples: 147,17 6~~~~

~~~~Oligochaetaspec . Samples:6 , 13,26 ,27 ,37 ,49 ,68 ,79 ,82 ,109 ,140 ,147 ,152 ,154 ,175 , 196,22 6~~~~

~~~~Pontodriluslltorall s Samples:1 0~~~~

~~~~Polychaetenondetermineerbaa r Samples: 17,19 ,31 ,36 ,47 ,52 ,54 ,59 ,69 ,89 ,90 ,126 ,135 ,141 ,143 , 145, 170,176 ,190 ,194 ,226 .~~~~

~~~~Sipinculldaspec . Samples:6 , 11,26 ,33 ,40 ,90 ,140 ,153 ,159 ,170 ,176 ,194 ,20 0~~~~

~~~~Nemertineaspec . Samples:28 ,44 ,147 ,154 ,18 5~~~~

~~~~Nematodaspec . Samples:73 ,14 7 Other speciesrecorde db yAltenbur g etal .(1982 )are :~~~~

~~~~Ehlersla cornuta ) Spionidaespec . )foun d insample sfro mmudd yZoster a Clymeninaespec . )~~~~

~~~~Perinereisoliveir a ) Scolaricia typica )foun d insample sfro msand ybiotope slik e Scoloplosmadagascariensi s )beache s~~~~

~~~~!10 _•-»«'~~~~

~~~~16. DISTRIBUTION, BIOMASS, RECRUITMENT AND PRODUCTIVITY OF ANADARA SENILIS~~~~

~~~~WimJ .Wolff ,Abo uGueye ,Andr éMeijboom ,Theuni sPiersm a andMamado uAlassan eSai l~~~~

TheWes tAfrica nblood ycockl eAnadar a senilis (L.)(als oknow na sAre a senilis)occur sfro m theforme rRi od eOr oi nth enort h toAngol a inth e south (Nicklès 1950).Littl e isknow nabou t itsecology .Yong e (1955) presentsa shor taccoun t ofit shabits .Yoloy e (1976)give sdat ao n distributionan decolog y ofth especie si nGhan aan dNigeria .Gjangma he t al. (1979)giv esom ephysiologica ldat ao ntoleranc e oflo wsalinities . Altenburg etal .(1982 )encountere d thespecie si nlarg enumber so n thetida lflat so fth eBan cd'Argui n inMauritania .I nthei rsample sfro m different localitieso nth eBan cd'Argui nA .senili sha da naverag e 2 biomasso f4. 7 gash-fre edr yweigh t perm ,thu saccountin g forabou t 60%o fth etota lbiomas s ofal lmacrobenthi sanimal s livingo nth etida l flats. Hencew epai d specialattentio n tothi sspecie sdurin g theprojec t Bancd'Argui n 1985-86. Datao ndistribution ,ecology ,biomass ,recruitment ,growth ,mortalit y andproductivit y ofth eWes tAfrica nblood ycockl eAnadar a seniliswer e collected atth eBan cd'Arguin ,Mauritania ,i nearl y 1985an d1986 . Ash-freedr yweigh tappeare d tob ecorrelate d bestwit hshel lheight .A . seniliswa sabundan t onth etida lflat so flandlocke d coastalbays ,bu t nearlyabsen t onth etida lflat sborderin g theope nsea .Th eaverag e

220 -2 biomassfo rth eentir eare ao ftida lflat swa sestimate d at 5.5g. m ash-freedr yweight .Th eA .senili spopulatio nappeare d toconsis tmainl y of 10t o20-year-ol d individuals,showin ga ver yslo wgrowt han da production :biomas s ratioo fabou t0.0 2y .Recruitmen t appeared negligiblean dmortalit ywa sestimate d tob eabou t 10%pe ryear . Oystercatchers (Haematopusostralegus) ,th egastropo d (Cymbiumcymbium ) andunknow nfis hspecie swer e reponsiblefo ra larg e shareo f this.Th e distinctiono fannua lgrowt hmark spermitte d theassessmen t ofyear-clas s strength,whic happeare d tob ecorrelate d with theaverag e dischargeo f therive rSenegal .Thi sma yb eexplaine d byassumin g thatyear-clas s strengthan d riverdischarg ebot har ecorrelate dwit hrainfal la tth e Bancd'Arguin . Adetaile d accounto fthi sstud y isgive ni nth eNetherland sJourna l ofSe aResearc h 21:243-253 .

~~~~221 17. FISHES AND SHRIMPS ON THE TIDAL FLATS~~~~

~~~~PierreCampredo nan dBe nSchrieke n~~~~

Asstate d inth eintroductio no f this reporti ti spossibl etha tsmal l fishan d invertebratesmigratin gwit h thetide sbetwee nth etida l channelsan d thetida lflat sconstitut ea nadditiona lsourc eo ffoo dfo r waders.T o test thishypothesi sw ehav emad ea fe whaul swit ha smal l trawli nMarc h 1986.Thes edat aar einsufficien t foran yconclusions . However thelatte rautho rha d started aserie so fsimila rhaul si n December 1984,whic hwer econtinue d in198 5b yth eforme rauthor . Togetherw ehav edat aavailabl efro m 20haul sbetwee nDecembe r 1984an d December 1985an d from 5additiona lhaul si nMarc h1986 . Allsample swer etake nwit ha smal l (2m)bea mtraw lwit ha counter . Thefirs t 20haul shav esample d 4578m .I nthes esample sw ecaugh t226 6 fisho f 19differen t speciesan d 9244prawn so f 10differen t species (Table 17.1). 7455Prawn sbelonge d toth especie sPalaemo nelegans . Furthermorew ecaugh t smallnumber so fcrabs ,amphipod san disopods . A smallnumbe r ofspecie shav ebee nfoun dexclusivel y inth eseagras s beds,viz .th efishe sE .guttiferum ,S .spengleri ,T .guineensi s (??),C . baillonian dL .nuchipinni san d theprawn sP .adspersus .S .typhl ean dS . hispidusals opreferre d seagrassbeds ,bu tth eflatfis hspecie sC . stampflii,D .azevi aan dD .cuneat awer ecaugh tove rsan dbottoms . Insumme r thenumber so fsom especie sincrease ,especiall y forth e fishspecie sP .microps/marmoratus ,S .typhle ,E .guttiferu man dS . hispidus,an d forth eprawn sP .kerathurus ,P .adspersus ,an despeciall y

~~~~22: Table 17.1. List of species of fish, prawns and crabs caught.~~~~

Pisces (fishes) Gynglymostoma cirratum (Bonnaterre 1788) Atherlna cf. loperiana Rossignol & Blache 1961 Syngnathus typhle Linnaeus 1758 Syngnathus cf. abaster Risso 1826 Ephinephelus aenaeus (Geoffroy Saint Hllaire 1817) Ephinephelus guaza (Linnaeus 1758) Dicentrarchus punctatus (Bloch 1792) Tilapia guineensis (Bleeker 1862)- identification not certain Dlplodus sargus Linnaeus 1758 Pomadasys incisus (Bowdich 1825) Sparus caeruleostictus (Valenciennes 1830) Crenilabrus bailloni Valenciennes 1839 Labrisomus nuchipinnis (Quoy & Gaimard 1824) 2) Pomatoschistus marmoratus /microp s Gobius niger Linnaeus 1758 Gobius paganellus Linnaeus 1758 Bathygobius casamancus Citharichthys stampflii (Steindachter 1894) Dicologlossa azevia Capello 1867 Dicologlossa cuneata (Moreau 1881) Stephanolepis hispidus (Linnaeus 1766) Ephippion guttiferum (Bennett 1831) Sphaeroides spengleri (Bloch 1782) Lagocephalus laevigatus (Linnaeus 1766)

~~~~Crustacea Decapoda~~~~

~~~~Penaeaidea (prawns) Gennadas spec. Penaeus notialis Perez Farfante 1967 Penaeus kerathurus (Forskal 1775) Sicyonia carlnata (Brünnich 1768)~~~~

Caridea (prawns) Leander tenuicornis (Say 1818) Palaemonadspersu s Rathke Palaemon elegans Rathke Hippolyte longirostris (Czerniavsky) Latreutes fucorum Fabricius 1798 Pontophilus fasciatus (Risso 1816)

~~~~!23 Brachyura (crabs) Callinectes marginatus A. Milne-Edwards 1863 Microcassiope minor Dana 1852 Macropodia spec. Pseudopagurus granulimanus~~~~

~~~~1) Our specimens have not been identified to species level,bu t Sevrin-Reyssac & Richter found this species. 2) Without males in breeding conditions further identification is not possible.~~~~

P.elegans . Shrimpso fth egenu sPanaeu sliv eoffshor ea sadult san d reproducei n Mauritanianwater s fromMa y tillAugust .Th elarva ear efoun d ininshor e waters;the ymigrat e totida lflat sdurin gnightl y high tides.Palaemo n adspersus reproduces offshore insummer ;afterward sadult san dlarva e migrate shoreward.P .elegan si sa nestuarin e specieswhic h isabl et o produce severalbatche so fegg sa year .W efoun d individualswit hegg s betweenMa yan dDecember .I nNovembe r 50%o fth especimen scarrie deggs .

~~~~22^ lit —1 <—1 —' I I I I I — I I I I I I II~~~~

~~~~I I I I I I + I I I I I I III II~~~~

~~~~llll — l + lll—'II I I I I I -.--.~~~~

~~~~I I I I CM I I I I I I I —. I I I I I I —~~~~

~~~~O .O vo m i -< i i i i i i i i i i i I—-ill il •o oo —i c et)~~~~

~~~~I—'I ! o I r-~ —. | —, | — I CM CM~~~~

~~~~3 licMiiimiiii—< co X.~~~~

~~~~-H I CM~~~~

~~~~01 c~~~~

~~~~CO C CO n i m — i I i —. i vc + I CU o CO~~~~

~~~~3 U O i looi I i o -a- I vo I I I I I I o> I II~~~~

~~~~•o e CO oo —• CM i I I loi I en i I i Ills*-» II Cv~~~~

~~~~co I I I I I l m CM i i i i i -cf i I i l il en CM~~~~

~~~~I I I I l l -a- m i —~~~~

~~~~a o cu~~~~

•i E CO 3 •H CO co x Z C 3 3 cr. x a. a. c -u U *H 3 E x CU •*-( CO —I CO 3 CU 3 ^ X x —I cu co x to o. i- t*j co AJ *^ •—' .£ a ki c Li CO -H T3 3 3 -H O »-. PL, -H CO -H 00 i-i v cu co .c c J= —i ce oo x. e m B > cu a. c co x o. oc x •H û. 00 C U CJ iJ Û0 CO CU C X cu l-i U X cu cu ti X c U CO 3 eg T4 4J N 3 ~4 a. CU C "D 'H U CO -rH eu u o co co c e C CO CO U X CO r-l Jd c to cu u JO CO X I- e e CO 4) E-i >> T.

~~~~225 Table 17.3. Numberso fspecimen so ffis han dcrustacean sobtaine d intraw lhaul sove rseagras sbeds .~~~~

~~~~Year 1984 1985 Date 12/8 12/8 6/17 6/17 10/21 10/21 11/22 11/22 11/22 12/8 12/8~~~~

G.cirratur n Atherinasp . 30 S.typhl e 10 7 34 46 35 20 24 20 14 12 Ephinephelussp . 13 8 14 4 3 T.guineensi s(?? ) 21 2 1 10 D.sargu s 1 86 139 C.baillon i 3 11 L.nuchipinni s 3 - - 1 - - - - P.marmoratus/microp s 26 52 282 105 9 - 185 39 12 1 - G.nige r 22 27 30 30 12 18 6 1 12 C.stampfli i : 2 ; D.azevi a ~ S.hispidu s 53 37 7 3 13 7 E.guttlferu m 13 18 - 21 47 1 1 S.spengler i - - - 1 - 2 -

2 3 P.kerathuru s - - - - 25 71 P.nothiali s 3 14 - - 275 260 18 18 ) P.adspersu s 12 13 few - 1288 700 1400 13 873 P.elegan s 13 760 1200 880 - 400 1000 955 37 + L.tenuicorni s 2 ) L.fucoru m 3 _ _ _ _ _ P.fasciatu s 3 H.longirosti s 30 86 176 32

~~~~C.marginatu s M.mino r Macropodia~~~~

~~~~226 Table 17.A. Numericaldensitie so ffis han d shrimpsove r thetida lflat s ofth eBai ed'Aouati f athig htide .~~~~

~~~~Month~~~~

Sand No hauls 2 - 2 2 3 Totallengt hhaul s 392 - 420 413 770 No fish/m 0.43 - 0.430.1 2 0.17 No gobies/in 0.35 - 0.340.1 0 0.10 No shrimps/m 0.09 - 0.220.2 1 0.00 2 No P.elegans/ m 0.08 - 0.11 0.09 0.00

Seagrass No hauls 2 2 3 4 Totallengt hhaul s - 483 420 658102 2 Nofish/m 2 -1.5 8 0.620.6 8 0.24 Nogobies/m 2 -0.8 0 0.020.3 5 0.07 Noshrimps/m 2 -4.5 4 7.785.3 1 1.88 NoP .elegans/m 2 -4.3 6 6.58 5.28 0.89

~~~~227 13. RECOMMENDATIONS FOR THE MANAGEMENT OF'~~~~

~~~~THE PARC NATIONAL DU BANC E>' ARGUIN~~~~

Although theMauritania nauthoritie sar ewel lawar eo fth eimportanc eo f thePar eNationa ld uBan cd'Argui nan dhav edevelope da wel ldesigne dse t ofmanagemen t regulations someo fou robservation smigh tb eusefu lfo r thedail ymanagemen t ofth ePare .

Permanenceo ffoo t printsan dhuma ntrail so nth etida lflat s Ondifferen t occasionsw ehav emad eobservation so nth etim erequire dt o removeb ynatura lprocesse sfoo tprint san dhuma ntrail so nth etida l flats. Onsand y shores theimpac t ofpeopl ewalkin g overth eflat swa sver y slightan d the traceslef tha ddisappeare d afteron eo rtw otides . Onmudd y shoresth eimpac to fwalkin g peoplewa smuc hgreate ran d traceswer evisibl elonger .O nth ever ymudd yshore s (wherepeopl esin k knee-deep inth emu dwhe nthe ytr yt owalk )th etrace slaste da tleas t twomonths .O nth eothe rhan dw erevisite d oneo fou rver ymudd y 1985 sitesi nFebruar y 1986.I nApri l 1985thi ssit eha dbee nmarke d bysmal l sticksan d inorde r tope gou t these stickspeopl eha dwalke d aroundth e entireperimete ro f thesite .A t that timethei r traceswer ever ydeep . OnFebruar y 1986,afte rabou t 10months ,thes etrace scoul dno tb efoun d backi nth efiel dalthoug hth estick swer estil li nplace .A ton espo t onlysmal ldepressions ,2- 3c mdeep ,occurred ,possibl yrepresentin gth e remnantso fa knee-dee phuma ntrai li n1985 . Weconclude d thathuma n trailsfro mth etida lflat swil ldisappea r againdu et oth eaction s ofth etides ;o nsand yflat sthi swil lhappe n withina fe wtides ,bu to nver ymudd y flatsthi sma y takeabou ton eyear .

Protectiono fturtle s Turtlesar ecaugh t regularlyb yth eImraguen .Th eworldwid eendangere d stateo fthes eanimal s leadst oth esuggestio nt oappl yprotectio n measures. Apossibilit ywoul d betha t thePar eNationa lbuy sth eturtle san d setsthe mfre eagain .Thi scoul d befinance db yWWF .

~~~~228 19. REFERENCES~~~~

Altenburg,W. ,M .Engelmoer ,R .Me s& T .Piersm a 1982.Winterin gwader s onth eBan cd'Arguin ,Mauritania .Repor to fth eNetherland s OrnithologicalMauritani aExpeditio n 1980.Comm .nr .6 ,Wadde nSe a Working Group,Stichtin gVet hto tSteu naa nWaddenonderzoek ,Leiden . AltenburgW. ,M .Engelmoer ,R .Me s& T .Piersm a 1983.Recensemen tde s Limicolese tautre soiseau xaquatique sa uBan cd'Arguin ,Mauritanie . Gerfaut 73:243-264 . Bowes,A. ,P.C .Lac k& M.R .Fletche r 1984.Winterin ggull s inBritain , January 1983.Bir dStud y31 :161-170 . Brederode,N.E .van ,M .Kersten ,T .Piersm a& P .Zeger s 1982.Netherland s waderexpeditio n toMorocc o 1982- som epreliminar y results.Wade r StudyBull .36 :12-14 . Brown,L.H. ,E.K .Urba n& K .Newma n 1982.Th eBird so fAfrica ,Vol .1 . Acad.Press ,London . Bub,H . 1969.Vogelfan gun d Vogelberingung.Vol .4 ,Neu eBreh mBücherei , WittenbergLutherstadt . Busse,P .& W .Kani a 1970.Operatio nBalti c 1961-1967workin gmethods . ActaOrn .12 :231-267 . Cramp,S .& K.E.L .Simmon s (eds.)1977 .Th eBird so f theWester n Palearctic,Vol .1 .Oxfor dUniversit yPress ,Oxford . Cramp,S .& K.E.L .Simmon s (eds.)1983 .Th eBird so f theWester n Palearctic,Vol .3 .Oxfor dUniversit yPress ,Oxford . Campredon,P . 1987.L areproductio nde soiseau xd'ea usu rl ePar c Nationald uBan cd'Argui n (Mauritanie)e n 1984-1985.Aland a55 : 187-210. DavidsonN.C .1981 .Seasona lchange si nth enutritiona lconditio no f shorebird sdurin gnon-breedin g seasons.Ph.D .Thesis ,Universit yo f Durham. Davidson,D.C . 1983.Formula e forestimatin g thelea nweight san dfa t reserveso fliv eshorebirds .Ring .& Migr .4 :159-16 6 DavidsonN.C . 1984a.Ho wvali d arefligh t rangeestimate s forwaders . Ring.& Migr .5 :49-64 . Davidson,N.C .1984b .Change s inth econditio no fDunlin san dKnot s duringshort-ter mcaptivity .Com .J .Zool .62 :1724-1731 . Dement'ev,G.P .& N.A .Gladko v 1954.Bird so f theSovie tUnion ,Vol .5 , Moskva.

229 Dick,W.J.A . (ed.)1975 .Oxfor d andCambridg eMauritani a expedition 1973 Report.Unpublishe d report,Cambridge . Dick,W.A. ,M.W .Pienkowski ,M .Walte r& C.D.T .Minto n 1976.Distributio n andgeographica l originso fKno tCalidri scanutu swinterin g inEurop e andAfrica .Arde a 64:22-4 7 Dick,W.J.A. ,T .Piersma ,P .Prokosc h 1987.Sprin gmigratio no fth e SiberianKnot sCalidri scanutu scanutus :result so fa co-operativ e WaderStud yGrou pproject .Orni sScand .18 :5-16 . Djangmah,J.S. ,S.E .Shumwa y& J .Davenpor t 1979.Effect so ffluctuatin g salinity onth ebehaviou r ofth eWes tAfrica nbloo dcla mAnadar a senilisan d onth eosmoti cpressur ean d ionicconcentration s ofth e haemolymph.Mar .Bio l 50:209-213 . Dowsett,R.J . 1971.Suspende dwing-moul ti nmigrants .Bir d Study18 : 53-54. Dowsett,R.J .& C.H .Fr y 1971.Weigh t losseso ftrans-Sahara nmigrants . Ibis 113:531-533 . Dijk,A.J .van ,K .va nDijk ,L.J . Dijksen,T.M . vanSpanj e& E .Wymeng a 1986.Winterin gwader san dwaterfow li nth eGul fo fGabès ,Tunisia , January-March 1984.WlWO-repor t 11,Zeist . Elliott,C.C.H. ,H .Waltner ,L.G .Underhill ,J.S .Pringl e& W.J.A .Dic k 1976.Th emigratio nsyste mo fth eCurle wSandpipe rCalidri sferrugine a inAfrica .Ostric h47 :191-213 . Engelmoer,M . 1982.Th eimportanc eo f theBan cd'Argui n forwinterin g waders.In :W .Altenburg ,M .Engelmoer ,R .Me s& T .Piersma .Winterin g waderso nth eBan cd'Arguin ,Mauritania .Stichtin gVet hto tSteu naa n Waddenonderzoek,Leiden :p .91-100 . Engelmoer,M . 1984.Analyse sva nbiometrisch egegeven sva n 12soorte n holarctischesteltlopers .Report ,Staatsbosbeheer ,Utrecht . Engelmoer,M. ,K .Roselaar ,G.C .Boer ean dE .Nieboe r 1983.Post-morte m changes inmeasurement so fsom ewaders .Ring .& Migr .4 :245-248 . Etchécopar,R.D .& F .Hu e 1964.Le sOiseau xd unor dd el'Afrique ,d el a MerRouge ,au xCanaries .Boubêe ,Paris . Etheridge,B . 1971.Weight san dmeasurement s ofwader swinterin g inth e TrucialStates ,Arabia .Wade r StudyGrou pBull .3 :5-7 . Evans,P.R . 1986.Correc tmeasuremen t ofth ewing-lengt ho fwaders .Wade r StudyGrou pBull .48 :1-1 1 Ferns, P.N. 1980.Th esprin gmigratio no fRinge dPlover sthroug h Britain.Wade r StudyGrou pBull .29 :10-13 .

230 Ferns,P.N .& G.H .Gree n 1979.Observation s onth ebreedin g plumagean d prénuptialmoul t ofDunlin sCalidri salpin acapture d inBritain . Gerfaut 69:287-303 . Glutzvo nBlotzheim ,U.N. ,K.M .Baue r& E .Bezze l 1975.Handbuc hde r VögelMitteleuropas ,Ban d 6.Akademisch eVerlagsgesellschaft , Wiesbaden. Glutzvo nBlotzheim ,U.N. ,K.M .Baue r& E .Bezze l 1977.Handbuc hde r VögelMitteleuropas ,Ban d 7.Akademisch eVerlagsgesellschaft , Wiesbaden. Goede,A.A .& E .Nieboe r 1983.Weigh tvariation s ofDunlin sCalidri s alpinadurin gpost-nuptia lmoult ,afte rapplicatio no fweigh tdat a transformations.Bir d Study 30:157-163 . Green,G.H . 1980.Tota lhea d length.Wade rStud yGrou pBull .29 :1-18 . Griffith,J . 1968.Multi-moda l frequencydistributio ni nbir d populations.Bir d Stduy 15:29-3 2 Hancock,J . 1984.Fiel didentificatio no fWes tPalearcti cwhit eheron s andegrets .Britis hBird s77 :451-457 . Hickling,R.A.0 . 1954.Th ewinterin ggull si nBritain .Bir dStud y1 : 129-148. Hickling,R.A.0 . 1967.Th einlan dwinterin ggull si nEngland .Bir dStud y 14:104-113 . Hickling,R.A.0 . 1977.Inlan dwinterin ggull s inEnglan dan dWales .Bir d Study24 :79-88 . Johnson,C . 1985.Pattern so fseasona lweigh tvariation s inwader so nth e Wash.Ring .& Migr .6 : 19-32. KerstenM .& T .Piersm a 1983.Wade rstudies .In :M .Kersten ,T .Piersma , C.Smi t& P .Zeger s (eds.).Wade rmigratio nalon g theAtlanti ccoas t ofMorocco ,Marc h 1981.RIN-repor t 83/20,Rijksinstituu tvoo r NatuurbeheerTexel :47-117 . Kersten,M .T .Piersma ,C .Smi t& P .Zeger s 1983.Wade rmigratio nalon g theAtlanti c coast ofMorocco ,Marc h 1981.RIN-repor t 83/20, Rijksinstituut voorNatuurbeheer ,Texel . KerstenM .& T .Piersm a 1987.Hig hlevel so fenerg yexpenditur ei n shorebirds;metaboli cadaption s toa nenergeticall y expensivewa yo f life.Arde a 75:175-187 . Knight,P.J . &W.J.A .Dic k 1975.Recensemen t deLimicole sa uBan c d'Arguin (Mauritanie).Aland a 43:363-389 . Lamarche,B .1987 .List ecommenté ede soiseau xd eMauritanie .Unpubl .

231 report,Nouakchott . McNeil,R .& F .Cadieu z 1972.Numerica l formulae toestimat e flightrang e ofsom eNort hAmerica n shorebirds from freshweigh tan dwin glength . Bird Banding 43:107-113 . Moser,M.E . (ed.)1980 .Shorebir d studies inNort hWes tMorocco .Repor t Department ofZoology ,Durham . Nicklès,M . 1950.Mollusque s testacêsmarin sd el acôt eoccidenta l d'Afrique.Manuel souest-africains .Pau lLechevalier ,Paris :1-269 . Nie,N.H. ,C.H .Hull ,J.G .Jenkins ,K .Steinbrenne r& D.H .Ben t1975 . SPSSStatistica lPackag efo rth eSocia lSciences ,secon dedition . McGraw-Hill,Ne wYork . Pearson,D.J . 1984.Th emoul t ofth eLittl e Stint Calidrisminut ai nth e Kenyan riftvalley .Ibi s 126:1-15 . Petterson,J .& D .Hasselquis t 1985.Fa tdepositio nan dmigratio n capacityo fRobin sErithacu s rubeculaan dGoldcres tRegulu s regulusa t Ottenby,Sweden .Ringin g& Migratio n 6:66-76 . Pienkowski,M.W . (ed.)1972 .Universit y ofEas tAngli aExpeditio nt o Morocco 1971Report .Unpublishe d report,Norwich . Pienkowski,M.W . 1980.A ne wWS Gdat afor man dprospect sfo ranalyses . WaderStud yGrou pBull .28 :11-14 . Pienkowski,M.W .& W.J.A .Dic k 1975.Th emigratio nan dwinterin go f DunlinCalidri salpin ai nNort hWes tAfrica .Orni sScand .6 :151-167 . Pienkowski,M.W. ,P.J .Knight ,D.J . Stanyard& F.B .Argyl e 1976.Th e primarymoul to fwader s onth eAtlanti ccoas to fMorocco .Ibi s118 : 347-365. Pienkowski,M.W .& P.R . Evans 1984.Migrator y behaviouro fshorebird si n theWester nPalearctic .In :J .Burge r& B.L .011 a (eds.).Shorebirds , migrationan d foragingbehaviour .Behaviou ro festuarin eanimals ,Vol . 6.Plenu mNe wYork :73-123 . Piersma,T .1982 .Foragin g ofBar-taile dGodwits .In :W .Altenburg ,M . Engelmoer,R .Me s& T .Piersma .Winterin gwader so nth eBan cd'Arguin , Mauritania.Stichtin g Veth totSteu naa nWaddenonderzoek ,Leiden :p . 135-148. Piersma,T . 1984.Estimatin g energy reserveso fGrea tCreste dGrebe s Podicepscristatu so nth ebasi so fbod ydimensions .Arde a 72:119-126 . Piersma,T . 1984.Internationa lwade rmigratio nstudie salon g theEas t AtlanticFlywa y spring 1985.Fina lannouncemen t ofa Wade rStud yGrou p project.Wade r StudyGrou pBull .42 :5-9 .

232 Piersma,T. ,N.C .Davidso n& P.R .Evan s 1984.Estimatio no f theprotei n reserveso fwaders :th eus ean dmisus eo fStandar dMuscl eVolume . WaderStud yGrou pBull .42 :19-22 . PiersmaT. , 1986.Breedin gwader s inEurope .A revie wo fpopulatio nsiz e estimatesan da bibliograph y ofinformatio n sources.Wade r StudyGrou p Bull.48 ,Suppl. : 1-116. Piersma,T. ,A.J .Beintema ,N.C .Davidson ,OA GMunste r& M.W .Pienkowsk i 1987.Wade rmigratio nsystem si nth eEas tAtlantic .Wade r StudyGrou p Bull.49 ,Suppl./IWR BSpecia lPubl .7 :35-56 . Portenko,L.A . 1959.Studie na neinige nseltene nLimicole nau sde m nördlichenun döstliche nSibirien .De rSichelstrandläufe r Erolia ferruginea.J .Orn .100 :141-172 . Prater,A.J. ,J.H .Marchan t& J .Vuorine n 1977.Guid et oth e indentificationan dagein go fholarcti cwaders .BT OGuid e 17,Tring . Rappoldt,C. ,M .Kerste n& C .Smi t 1985.Error si nlarge-scal eshorebir d counts.Arde a 73:13-24 . Reyssac,J . 1977.Hydrologie ,phytoplancto ne tproductio nprimair ed el a Baied uLévrie re td uBan cd'Arguin .Bull .IFA N(Dakar )39A :487-550 . Rosevear,D.R . 1969.Th erodent so fWes tAfrica .Britis hMuseum ,London : 604p . Salomonsen,F . 1955.Th eevolutionar y significance ofbir dmigration . Dan.Biol .Mead .2 2 (6): 1-62. Schick,C.T .1983 .Weigh tlos si nSanderling s Calidrisalb aafte r capture.Wade rStud yGrou pBull .38 :33-34 . Schütz,E. ,P .Berthold ,E .Gwinne r& H .Oelk e 1971.Grundris sde r Vogelzugskunde.Parey ,Berlin :39 0p . Sevrin-Reyssac,J . 1980.Chlorophyll eA e tproductio nprimair edan sle s eauxd el aBai ed uLévrie re td uPar cNationa ld uBan cd'Argui n (septembre-octobre 1980).Bull .Cent .Nat .Rech .Océanogr .Pêches , Nouadhibou 9:56-65 . Sevrin-Reyssac,J . 1981.Caractéristique sd uphytoplancto nd el arégio n del'îl eTidr a (Mauritanie)e nseptembr ee toctobr e 1980.Bull . Nat. Rech.Océanogr .Pêches ,Nouadhibo u (souspresse) . Smet,K .d e& J .va nGompe l 1979.Wade rcount sa t theSenegales ecoas ti n winter 1978-79.Wade r StudyGrou pBull .27 :30 . Smit,H . 1987.Vogeltellinge n opd eEngelsmanplaat .Limos a 60:111-118 . Speakman,J.R . 1987.Apparen t absorptionefficience s forRedshan k (Tringa totanusL. )an dOystercatche r (Haematopusostralegu s L.): implications

233 forth eprediction s ofoptima l foragingmodels .Am .Nat . 130:677-691 . Spencer,R .& R .Hudso n 1978.Repor t onbir d ringing for 1977.Ringin g& Migration 2:57-104 . Stanyard,D.J . 1974.A not eo nth eprimar ymoul t ofCalidri sminut a Little Stint inBotswana .Wade r StudyGrou pBull .12 :13-14 . Summers,R.W. ,L.G .Underhill ,M .Waltne r& D.A .Whitela w1987 . Population,biometric san dmovement so fth eSanderlin gCalidri salb a inSouther nAfrica .Ostric h58 :24-39 . Swennen,C . 1984.Difference si nmea nqualit ybetwee nroostin g flockso f OystercatchersHaematopu sostralegus .In :P.R . Evans,J.D . Goss-Custard &W.J .Hale .Coasta lwader san dwildfow l inwinter . CambridgeUniversit yPress ,Cambridge . Swennen,C , L.L.M.d eBruijn ,P .Duiven ,M.F .Leopol d &E.CL .Martij n 1983.Difference s inbil lfor mo f theOystercatche rHaematopu s ostralegus:a dynami cadaptatio n tospecifi cforagin gtechniques . Neth.J .Se aRes .17 :57-83 . Taylor,R.C .1980 .Migratio no f theRinge d PloverCharadriu shiaticula . OrnisScand .11 :30-42 . Trotignon,J . 1976.L anidificatio nsu rl eBan cd'Argui n(Mauritanie )a u printemps 1974.Alaud a 44:119-133 . Trotignon,E. ,J.M . Bailoon,J.F .Dejonghe ,D .Duhanto s& M .Lecompt e 1980.Recensemen thiverna lde slimicole se tautre soiseau xaquatique s surl eBan cd'Argui n (Mauritanie)(Hive r 1978/1979).L'Oiseau xe t R.F.0.50 :323-343 . Tye,A .& H .Ty e 1987.Th eimportanc eo fSierr aLeon efo rwinterin g waders.Wade rStud yGrou pBull .49 ,Suppl./IWR BSpecia lPubl .7 : 71-75. Urban,E.K. ,C.H .Fr y& S .Keit h 1986.Th ebird so fAfrica ,Vol .II . Acad.Press ,London . Voons,K.H .1973 .Lis to frecen tholarcti cbir d species,non-passerines . Ibis 115:612-638 . Voons,K.H . 1977.Lis t ofrecen tholarcti cbir d species,passerines .Ibi s 119:223-250 ,376-406 . Wilson,J.R. , M.A.Czajkowsk i& M.W .Pienkowsk i 1980.Th emigratio n throughEurop ean dwinterin g inWes tAfric ao fCurle wSandpipers . Wildfowl 31:107-122 . Yoloye,L . 1976.Th eecolog yo f theWes tAfrica nblood ycockl eAnadar a (Senilia)senili s (L.).Bull .Inst .Françai sd'Afriqu e Noire,Daka r

Î34 38:25-56 . Yonge,C.M .1955 .A not eo nAre a (Senilis)senili sLamarck .Proc . malacol.So c London 31:202-208 . Zwarts,L . 1984.Wadin gbird si nGuinea-Bissau ,winte r 1982/83.Wade r StudyGrou pBull .40 :36 . Zwarts,L . 1986.Th ewinte rexploratio n offiddle rcrab sUc atanger ib y waders inGuinea-Bissau .Arde a 73:3-12 . Zwarts,L . 1988.Number san ddistributio no fcoasta lwader s inGuine a Bissau.Ardea ,i nprep .

~~~~235 A F»£ >E ND X X~~~~

~~~~WADER BIOMETRICS~~~~

Piet Duiven 1 Oystercatcher (Haematopus ostralegus) 1.1Catche s 1985. Whenw earrive d inth e 'Pare'mos to fth eOystercatcher sha dlef t thestud yare aan dwer emigratin g towardsthei rbreedin ggrounds ,o rdi d alreadyarriv e there.B yth etim ew eactuall ycoul d startcatching ,onl y smallnumber so fOystercatcher swer estil lusin gth ehig htid eroost si n theBai ed'Aouati fan da tEbel kAizna y (NorthwestBay) .A sobserve d earlier (TheunisPiersma ,pers .comm. )th ebird swer efoun dver yshy .An d theonl ytw obird sw eeventuall y laidhand son ,wer ecaugh t on1 6Apri l 1985an d 29Apri l 1985,a nafte rthir d calendaryea ran da thir dcalenda r yearbir d respectively.

1986.Durin gou rsecon d staynin eOystercatcher swer ecaugh tnea rth e campsit eo nvariou sdate sbetwee nearl yFebruar yan dmi dApril .On eo f thebird swa sretrappe d inth esam eperiod .Mor emeasurement swer e obtained fromth eremain so fdea d Oystercatchers.On ewa sfoun da tEbel k Aiznayan d twoa tTidra .

1.2 Biometrics Allbird sbelonge d toth erac eostralegus .Se xwa sno tdetermined . Measurementsan dweight swer ecombine d intable s 1.1an d 1.2. Onaverag eweight swer elo wi nal lag eclasse si fcompare dwit hth e weightso fOystercatcher s fromth ewester nWadde nSe ai nearl ysprin g (Glutze tal . 1975).Howeve ron eha s tobea ri nmin d that themajorit yo f Oystercatchersha dalread ylef t theare aan dmos to fth estraggler s probablywer eno ti noptima lcondition .O fth esecon dcalenda ryea rbird s witha lo wbod yweigh t twower ei nful lwinte rplumag ea tth een do fth e firstdecad eo fApril .Th eothe ron ewa sjus thal fwa ytoward ssumme r

~~~~236 TOTAL HEAD , HM~~~~

~~~~ao 100 BILL LJENÄTH , MM~~~~

~~~~Figure l.l. The relationship between bill length and total head of Oystercatchers at the Banc d'Arguin, Mauritania. Y » 41.3766 + 1.01383x , r-0.992039.~~~~

plumage.Th eafte rthir d calendaryea rbird ,weighin g 480g ,wa si nful l winter plumagetoo .Anothe rafte rthir dcalenda ryea rbir d onlyweighe d 384g .On eo fth eleg so fthi sbir dwa smissin gfro mth eintertarsa l jointan dbeside s that,i twa sstil li nwinte rplumag ean dtw oo fth e primarieswer eno tmoulted .I twa sfoun dearlie r thatth eenumerate d aberrationsar eindication sfo ra poo rphysica lconditio n (Swennen 1984). Though theavailabl e samplei ssmal l (n=10)a clos erelationshi pha s beenfoun dbetwee nbil llengt han d totalhea d (Fig.1.1) .

~~~~Table 1.1. Weights (in gram) of Oystercatchers at the Banc d'Arguin,~~~~

~~~~Mauritania.~~~~

~~~~February March April 1-14 15-28 1-15 16-31 1-15 16-30~~~~

~~~~2nd c.y. 364 372 370~~~~

~~~~> 2nd c.y. 503 3rd c.y. 513 423 375~~~~

~~~~> 3rd c.y. 480 384 592 550~~~~

~~~~237 Table 1.2. Wing length, bill length, total head (» tohe)an d tarsus + toe (= tato) (in mm) of Oystercatchers at the Banc d'Arguin, Mauritania.~~~~

~~~~2nd c.y. 3rd c.y. > 3rd c.y.~~~~

~~Wing 235 247 252 247 257 258 259 259 259 266 Bill 70.7 76.9 76.9 78.8 68.0 78.7 75.3 88.2 89.0 70.7 Tohe 112.0 119.7 120.5 119.9 111.2 118.9 117.7 131.1 131.5 113.7 Tato 90 95 100 95 97 97 85 99 98 96~~

1.3 Billmorpholog yan dforagin g Sevenbil ltip s(• = 50%o fth etrappe dbird san d theremain so fth edea d ones)wer echise lshaped ,tw oha da pointe d bill,fou rwer eintermediat e betweenpointe dan dchise l shapedan don ewa s intermediatebetwee nchise l andhammer .Th ebil lshape sca nb erelate d toforagin g techniques (Swennene tal . 1983).Oystercatcher swit hchise lshape dbill swer e eatingmolluscs .I nbot hyear sprincipall y thebivalv eAnadar a (Area) seniliswa sfe dupon .I n198 6th eforagin gbehaviou ro fOystercatcher s wasstudie d indetai l (Swennen,chapte r 13).Bird swit hpointe dbill s foraged onworms .O nth etida lflat s theyspeciall ywer efeedin go nth e largerpolychaetes ,probabl yNerei sfals aan dMarphys asanguinea .I n certainarea salon g themainlan d coastlineOystercatcher s (andBar-taile d Godwits)wer eobserve d foragingver yactively .I nbotto msample swa s undersom ec mo fsan da laye ro f5-1 0c mo fZoster awrack .I nth erottin g Zosterahig hdensitie so fth emarin eoligochaet ePontodrilu s litoralis werefound .Afte rhig htid eth eOystercatcher s followed thefallin gtid e andnort ho fEbel kAizna ythe ywer eabl et ocom et oa nestimate dfoo d intakebetwee n 11an d 18g ash-fre edr yweigh twithi non ean da hal f hour.

~~~~238 ^^fL~~~~

TheunisPiersm a 2Avoce t (Becurvlrostaavosetta ) Mucht oou rsurpris ew efoun dAvocet si nou rmis tnet so nth eevenin go f 25Marc h 1985(mor eindividual s thanw eha d seenu ptil lthen!) .Th e measurementsmad eo nthes ebird s (both> secon dcalenda ryea rbirds )ar e listed intabl e2.1 .Tw oAvocet swit hcolou rring swer esighte do n2 9 March1986 .Bot hwer eringe di nMa y 1984nea rHolwerd ,Friesland ,Th e Netherlands,a sbreedin gadults .On ewa ssighte d lateri nsprin g (on1 9 April 1986)i nth eLauwersmeer ,Th eNetherlands ,an d thesecon dwa s resighted on1 5Apri l 1986nea rHolwer d (M.Engelmoer ,pers .comm.) .I t tookthe mtherefor ea maximu mo ftw oweek st ofl yfro mth eBan cd'Argui n toth eDutc hWadde nSea .

~~~~Tabel 2.1. Measurementso ftw oadul tAvocet so n1 5Marc h 1985nea r Iouiko nth eBan cd'Arguin .~~~~

~~~~Bird1 Bird 2 (ringF T92008 ) (rinf; F T92009 )~~~~

~~217 Winglengt h(mm ) 223 Billlengt h(mm ) 84.2 70.9 Totalhea dlengt h(mm ) 127.2 119.1 Tarsus+ to elengt h(mm ) 133 125 Bodyweigh t(g ) 261 275 reddishbrow n Colouro firi s brown (female?) (male?)~~

~~~~239 MJ%K~~~~

3Ringe d Plover CorJ .Smi t 3.1 Introduction Thenumbe ro fwinterin gRinge dPlover so nth eBan cd'Argui namount st o about 100,000(Altenbur ge tal . 1982),whic hi ssomewha tmor e than4 %o f thetota lwade rnumber .Th especie s therefore isranke da t thefift h place,afte rDunlin ,Bar-taile dGodwit ,Kno tan dCurle wSandpiper .Durin g lowtid eRinge dPlover sar emos tnumerou so nbarre nsandflat s (about4 birdspe rhectare) .Number so nmudd yan d sandyseagras sflat san dmudd y Area-flatsar ei nth eorde ro f 1-2birds/h a (Altenburg etal .1982) . RingedPlove rnumber si nth eBai ed'Aouati f on2 4Marc h 1985amounte dt o somewhatove r 4500birds ,whic hwa sles stha nhal f thenumbe rcounte di n January 1980.Thi ssuggest s thatb yth een do fMarc ha considerabl e proportiono fth ewinterin gnumbe ro fRinge d Ploversalread yha sleft . Numbersdeclin efurthe ri nth ecours eo fApril .O n2 5Apri l 1985300 0 RingedPlover swer ecounte d inth eBai ed'Aouatif .Number s inEbel k Aiznaivarie d from 180t o54 0an ddi dno tsho wa systemati ctrend .

3.2 Catches Thetota lnumbe r ofcapture dRinge d Ploversamounte d to78 ,2 4o fthes e being second calendaryea rbirds .On ebir dcoul dno tb eage d successfully.Al lbu t9 bird swer ecapture d inmis tnet sa tvariou s placesi nth eBai ed'Aouatif .Th e9 wer epar to fa canno nne tcatc ho n8 April 1985.Dic k (1975)foun d considerabledifference s inth enumbe ro f juvenileRinge d Plovers inth e 1973catches ,th epercentag eo fjuvenile s gradually dropping fromearl yOctobe r tomid-November ,possibl ydu et o passageo f juveniles towinterin garea sfurthe r south.Recen tcount s (Zwarts 1988)sho wtha tsom e 57,000Ringe dPlover sar ewinterin gi n GuineaBissau ,wherea sanothe r 25,000ma yb eexpecte d towinte ri nSierr a Leone (figurecalculate d fromdat ai nTy e& Ty e 1987). Inou rcatche sth e percentageo fsecon dcalenda ryea rbird sdi tno tchang ei nth ecours eo f

240 theseason ,bein g3 1an d30 %i nMarc han dApril ,respectively .Juvenile s couldno tb esexe d successfully.Amon gth eadult s2 3coul db esexe da s male,3 a sfemale .Anothe r2 7coul dno tb esexe d successfully.I tshoul d bekep ti nmind ,however ,tha tmale sca nmor eeasil yb esexe d (Pratere t al. 1977).Ther ewer e4 retraps ,th ebiometrica ldat ao fthes ear egive n intabl e3.1 .

~~~~Table 3.1. Biometrical data of4 Ringed Plovers captured twice.~~~~

~~~~Ring Date Age Corrected Wing Bill Total Tarsus weight head + toe~~~~

SA 747096 25/3/85 6 51 136 14.1 41.8 47 10/4/85 6 53 137 14.3 41.5 48 SA 747334 10/4/85 6 56 136 15.0 40.6 46 9/3/86 6 51 134 13.9 40.5 46 SA 747336 11/4/85 6 52 131 15.0 42.0 46 9/3/86 6 49 132 14.9 41.9 46 SA 747554 19/4/85 6 62 130 13.8 39.7 44 22/4/85 6 57 131 14.2 40.2 44

3.3Biometric s Bodymeasurement so fRinge dPlover scapture di n198 5an d198 6ar egive n intabl e3.2 .Ther ear esignifican tdifference si nwin glengt h (t= 5.44 , p< 0.001) ,bil llengt h (t= 2.99 ,P < 0.01 )an dtota lhea dlengt h (t= 2.08,P < 0.05 )betwee nsecon d calendaryea ran dadul tbirds .Juvenil e billlength sar esomewha t smallera scompare d tomeasure s takeni n197 3 (t= 2.49 ,P < 0.05) .Adul tbil llength sar eexactl yth esame .Juvenil e winglength si nautum n 1973wer esignificantl ylarge r (t= 3.08 ,P < 0.01)a scompare d towinte r 1985/1986.Thi sma yb ea resul to ffeathe r abrasioni nth ecours eo fautum nan dwinter ,thoug hi tma yals ob edu et o thefac t thatdifferen t populationsar einvolved .Adul twin glength sd o notdiffe rsignificantly . A frequencydistributio no fbill ,win gan dtarsu splu sto elength s (Fig.3.1 )demonstrate stw odistinc tan don emino rpeak si nbil llengths , suggesting thatwithi nth ecatche stw oo rthre epopulation sca nb e distinguished.Thi sma ypartl yb eexplaine d bydifference sbetwee nsexes , butals oindicate s thata tleas ttw opopulation so fdifferen t originar e present.Tabl e3. 3show sthat ,a si nKentis hPlover ,fe wbiometrica l parametersar esignificantl ycorrelated .

~~~~241 1 SECOND CXI_eNDA.R' YEA«. M>UUT~~~~

~~~~FßEQüEWCV~~~~

~~~~126 13o 134 50 iSH 15S MIN~~~~

~~~~12 VJIN6 LENGTH 10 \~~~~

~~~~8 _ 6 - ^^ 2~~~~

~~~~^ • 111 - - 1 12« 126 128 130 132 134 136 133 140U N FREQ^OOCV~~~~

~~~~- TARSUS •*- TOE~~~~

~~~~12 — 10 â 6 n 2 'MM bsi m\ HI m H6 «ô 50 52 5^ S6 58 MIN~~~~

~~~~Figure 3.1. Frequency distribution ofbill ,win g andtarsu s+ to e lengths ofRinge d Plovers capt J it theBan c d'Arguin in 1985/1986.~~~~

~~~~242 Table 3.2. Body measurements (Inmm )o f Ringed Plovers at the Banc d'Arguln in February-April 1985an d 1986.~~~~

~~~~2nd c.y. Adult All birds average + S.D. average+ S.D. average + S.D. range, number range, number range, number~~~~

~~~~Wing length 128.2+ 2.8 132.2+ 3.0 130.9 + 3.4 123-134; n-24 124-138; n-52 123-138; n-77~~~~

~~~~Bill length 14.1+ 0.6 14.6+ 0.7 14.5+ 7.0 12.7-15.3; n-24 12.7-15.9; n-53 12.7-15.9;n-2 8~~~~

~~~~Total head 40.7+ 0.7 41.1+ 0.8 41.0+ 0.8 length 38.8-42.0; n-24 38.9-42.6; n-53 38.8-42.6;n-2 8~~~~

~~~~Tarsus + toe 45.3+ 1.5 46.0+ 1.6 45.8+ 1.6 43-48; n-23 43-51; n-53 43-51; n-77~~~~

Table 3.3. Correlation coefficients of corrected weight and biometrics of Ringed Plovers (allag e classes), n=78. Coefficients significant at the 0.05 level aremarke d with *, those at the 0.01 level with ** and those at the 0.001 level with ***.

~~~~Weight Wing Bill Total head length length length~~~~

~~~~Wing length 0.3007* Bill length 0.0189 0.1448 Total head length 0.0550 0.1459 0.5602*** Tarsus+ toe 0.1911 0.0371 - 0.1641 - 0.0667~~~~

~~~~Table 3.4. Corrected mean weights (grams)o f second calendar yearan d adult Ringed Plovers captured at the Bancd'Argui n in February-April 1985/1986.~~~~

~~~~Month 2nd c.y. Adult average + S.D. average + S.D. range, number range, number~~~~

~~~~February 43 (n-1) 54 (n=l)~~~~

~~~~March 47.1+ 2.2 49.4 + 4.2 43-50;n- 9 43-57; n=20~~~~

~~~~April 49.8+ 4.1 56.9+ 5.1 42-56; n=15 46-70; n=31~~~~

243 3.4 Weights Weightsuse d inthi schapte rhav ebee ncorrecte d forweigh t lossbetwee n catchingan dweighing .Al ltogethe r 25measure swer eavailable ,tim e intervals betweensuccessiv eweighin g ranging from 1.7-13.2hour s(mea n 7.3+ S.D .3.5) .Mea nweigh t lossamounte d to0.4 3g/hou r (+S.D . 0.37). Onaverag eRinge d Ploverswer ekep t 3.50hour s (+S.D .2.03 ,n « 74 ) betweencatchin gan dweighing .Correcte dmea nweight sar epresente di n table3.4 .Th edat asho wa weigh t increasebot hfo rsecon dcalenda ryea r andadul tbirds ,th eincreas ebein gmuc hmor eobviou sfo radults .Weigh t increase isals odepicte d infigur e3.2. ,showin g thesam epattern . Weightsi nMarc har ever ymuc hth esam ea scompare d tothos efoun do nth e Bancd'Argui n inSeptember-Novembe r 1973(Dic k 1975).Th elatte rautho r found juvenilesmeasurin g48. 5g + S.E .1. 5 (n=22),adult s50. 6g + S.E . 0.46 (n=49). Springweight si nMorocc ower e50. 1g ( +S.D .4.5 ;n=29 )fo r juvenilesan d 54.5g (+5.0 ;n=4 )fo radult s (Kerstene tal .1983) .Onc e again,thes eweight sar eextremel y lowa scompare d tosprin gweight so f RingedPlover si nwester nEurope .I nApril/Ma ymea nweight si nth eWas h werearoun d 70g ,th efe wbird scapture d inJun eeve nweighin g 10g mor e

~~~~WEi&HT,a~~~~

~~~~FEÖ H*ß APR.~~~~

Figure3.2 . Weights (grams)o fRinge d Plovers,capture da tth eBan c d'Arguin inFebruary-Apri l 1985/1986.Ope ncircle srefe rt osecon d calendaryea rbirds ,dot st oadults .Weight shav ebee ncorrecte dfo r weightlos sbetwee ncatchin gan dweighing .

244 (Johnson 1985).Figur e 3.2 showstha tweigh tincreas eo fRinge d Plovers at theBan cd'Argui nstart sfro mmid-Marc h onwards.Th esam efigur e suggestsa separatio ni ntw ogroup so fbirds ,accordin g toth edotte d line.A compariso no fwing -an dbil llength so fthos etw ogroup sdoe sno t showan ydifferences .W ema ytherefor eno tconclud etha tdifferen t populationsar einvolved .Neithe rther ei san yindicatio n thatthi s separationi sth eresul to fdifference sbetwee nsexes . Thefac ttha tRinge dPlove rnumber so n2 4Marc halread ywer ehal fo f thosecounte d inJanuar yindicate s thata considerabl e proportiono f thesebird swhic har eleavin g theBan cd'Argui n dos oa trelativel ylo w weights.Assumin g thatth epopulatio no fbird scapture d inou rmis tnet s isa representativ e sampleo fth epopulatio npresen ta tth eBan c d'Arguin,th ebird sleavin g theare ad os oa tweight so fapproximatel y 50g !Th elea nweigh to fa Ringe dPlove rma yb eestimate d at45. 4g (McNeil& Cadieu x 1972).Bird sleavin g inMarc h thereforewoul donl y carryabou t 5g o ffat ,allowin g themt ofl ysomewha t over50 0kilometer s (calculated fromequation si nDavidso n 1984).Thi swoul donl ybrin gthe m asfa ra sth eBa yo fDakhl ao rcoasta larea selsewher e inth eRepubli co f WesternSahara .Th eheavies tbird si nmid-Apri lar eapproximatel y 10g heaviera scompare d tothos ei nMarch .Thi sfa tloa dallow sthe mt ofl y about 1500km ,a sa resul to fwhic h theywoul db eabl e toreac hcentra l Morocco. Therear etw opossibl eexplanation sfo rth eextremel y lowfa tload s foundi nMarch .Firstl yw ema yno thav ecapture d relativelyheav ybird s inMarch .Thi si swel lpossibl esinc eth enumbe ro fRinge d Plovercatche s fromth efirs tpar to fMarch ,i sextremel ylimited .Th esecon d explanationma yb etha tRinge dPlover sleavin g inMarc hd ono tprepar e forlon gdistanc eflight sbu tar ecapabl eo fforagin galon g sandyo r rockycoast salon g theWes tAfrica ncoas tnort ho f theBan cd'Arguin . Quiteconsiderabl enumber shav ebee nfoun do nrock ycoast si nMorocc o indeed (Kerstene tal .1983 )wher ethe yappeare d tob eth emos tnumerou s waderspecies .O n 13Marc h 19847 5Ringe d Ploverswer ecounte d ona stretcho f 10k mbetwee nCa pBlan can dE lJadida .

3.5 Plumage Fromearl yMarc honward sRinge dPlover sstar tcomin g intosumme rplumag e (Fig. 3.3).Especiall yadul tbird sappea rt od oso .Th enumbe r ofsecon d calendar yearbird s inintermediat e orsumme r plumage isextremel ysmall .

~~~~245 Pi.UHA.CnE~~~~

~~~~J -~~~~

~~~~6 - •• • • • •~~~~

~~~~5 - • • t •- k - • t • • M •~~~~

~~~~3 o»« • •• •~~~~

~~~~2 O ••• • o •c ®~~~~

~~~~1 •~~~~

~~~~9 23 PEE» MAR M>«.~~~~

~~~~Figure3.3 . Plumageo fRinge dPlover sa tth eBan cd'Argul nI n February-April 1985/1986.Ope ncircle srefe rt osecon dcalenda ryea r birds,dot s toadults .~~~~

~~~~BODY MOULT WEAV^ 3 • •<~~~~

~~~~IKTTER.H2 • •«~~~~

~~~~LIGHT 1 §••• 8 t~~~~

~~~~fc- dB—8 «»«f tft godtp^ . S FEE. MAR AVR.~~~~

~~~~Figure3.4 . Bodymoul to fRinge dPlover si nth ecours eo fsprin ga tth e Bancd'Arguin .Ope ncircle srefe rt osecon dcalenda ryea rbirds ,dot st o adults.~~~~

246 Onlyon ebir dwa sfoun d tob ei nintermediat eplumage .Adul t birdscom e intoful lsumme rplumag eb yth een do fMarch .B yth een do fApri ladul t Ringed Ploversdispla ya blen do f intermediatean d fullsumme rplumages . Relatively fewbird shav ebee nfoun d tob ei nheav ybod ymoul t (Fig. 3.4).Mos tadul tbird sar ei nintermediat eo rligh tbod ymoul tan dth e numbero fbird sno tmoultin ga tal li srelativel y large,eve ni nth e second parto fMarc han di nApril .Th enumbe ro fjuvenile s foundmoultin g amounted to5 ,whic hequal sabou t 20%o fth etota lnumbe rcaptured .Fo r theadult sn orelatio ncoul db efoun dbetwee nmoultin g stagean dweight . Thisfindin g isi ncontras t todat afro mMorocc o 1981,wher emoultin g birds tended tob eheavie ra scompare d tonon-moultin g individuals (Kerstene tal . 1983).Tw obirds ,bot h juveniles,wer ei nactiv ewin g moult.One ,capture d on1 5Apri l 1985,weighin g 42g showe d following characteristics:5555530000 .Th esecon dbird ,capture d 9Marc h 1986 weighing 46g showe d 5550000000.Non eo fth ebird sshowe d signso ftai l feathermoult .

3.6 Geographicalvariatio nan dmigratio n RingedPlover shav eofte nbee nregarde da son eo fth etypica lspecie s showing leap-frogmigratio n (Salomonsen 1955,Pare ye tal . 1971).Thi s means thatth enorthernmos tbreedin g populationsar ewinterin g farthest south,thos ebreedin g furthersout hprogressivel ymigratin g overshorte r distances.A sa resul t thesouthernmos t breedingpopulatio n (Britain)i s almost residentan d iswinterin g farthestnorth .Breedin g populations fromelsewher e inNorthwes tEurop ehav ebee nfoun dwinterin g southt o NorthAfrica .Thos ebreedin g inIcelan dan dGreenlan d 'probably'winte r inWes tAfric awherea sbird sfro mnorther nScandinavi aan dnorther nUSS R winter inWes tAfric a (Pienkowski& Evan s 1984).Wes tEurop e issituate d ona crossroa d ofmigratio nroute sfro mNearcti can dPalearcti cbreedin g grounds,probabl yendin gu pi nth eGul f ofGuine aan d possiblyeve n furthersouth .Ther ear erecoverie s ofRinge dPlovers ,capture d inth e Washo nth eEnglis heas tcoast ,fro mMorocco ,Sénéga lan dBéni n(Branso n 1987).Nearcti can dNort hPalearcti cpopulation sd omi xi nAfrica nwinte r quarterswherea sconsiderabl enumber s (mainly theNort hPalearcti c 'tundrae'population )winte r inland inAfrica ,sout ho fth e 15thdegre e oflatitude ,alon g largeriver san dlake s (Pienkowski inCram pan d Simmons 1983).A recen tanalysi s ofrin g recoveries (Taylor 1980)show s thatth eleap-fro g conceptdoe sexis tbu t isles sdistinc t thanassume d

~~~~247 1 QR.EEK1V-AJ-ID 3 M. SCANDINAVIE * S\Vè.E«.\P^~~~~

~~~~2 ICELAND + VsJ. EUROPE 4 E.. PALEAR.T1C. BILL LENGTTW~~~~

~~~~15.5~~~~

~~~~o « • •~~~~

~~~~o • Q» • o o o o O o 4> o ;S> » • -ö> i35~~~~

~~~~\3.0~~~~

~~~~I2.S _L 120 122 12« 126 128 130 132 134 136 -13S AHO WINIG, LEMöTH~~~~

Figure 3.5. Wing length-bill length relation of Ringed Plovers captured at the Banc d'Arguin and mean lengths and standard deviations of Ringed Plover populations elsewhere (based onmuseu m skins,correcte d for shrinkage; Engelmoer 1984). Open circles refer to second calendar year birds, dots toadults .

bySalomonse n (1955).Figur e 3.5 showsth eresult so fth ewin g length-bill length relationo fRinge d Ploverscapture da tth eBan c d'Arguin in1985/1986 .Thi sgrap hals oshow sth emea nan dstandar d deviationso ffou rpopulation s ofRinge d Ploversbase do ndat asupplie d byEngelmoe r (1984).Base do nth eresult so fdiscriminan tanalysi sh ei s ablet oseparat eth efollowin gRinge dPlove rpopulations : 1)a lon gwinge dan drelativel y longbille d populationo fbird sfro m Iceland andWes tEurope ; 2)thre e populationswhic har eno tseparatabl eusin gdiscriminan t analysis,breedin g inGreenland ,norther nScandinavi aan dnorther nUSS R and theEas tPalearctic .Thes ethre epopulation sar echaracterize db y shorterwing san d shorterbills ,a scompare d toth efirs tone .

248 Obviously parto f theMauritania nmeasure scoincide swit h themeasure s ofth efou rpopulation sfro mfigur e 3.5.However ,quit ea lo to fmeasure s dono tfi twel lint o thesefou rpopulations .Thes eremainin g birdsar e especiallycharcterize d byrelativel y longbill san d shorter wings.Th e samerelativel ylon gbill san d shortwing shav ebee nfoun db y theOxfor d andCambridg eexpeditio n inautum n 1973(Dic k 1975). Infac t theiradul t billan dwin g lengthsdi dno tdiffe rsignificantl y fromvalue sfoun di n 1985/1986.Ther ear etw orecoverie so fbird sringe da tth eBan cd'Argui n in1985/1986 .Th efirst ,a nadul t ringed on8 Apri l 1985,wa scontrolle d inWale s (52°31'N,04°03'W )o n5 Ma yi nth esam eyear .Th esecond ,a n adultringe do n8 Februar y 1986,wa sfoun ddea do nth eFrenc hchanne l coast (50°59'N,01°56'E )o n1 0Augus t 1986.Th e 1973expeditio nyielde d recoveriesfro mIceland ,th eBalti can dMorocc o (Altenburge tal .1982) . Theserecoverie s strongly suggest (cf.Fern s 1980)tha ta tleas tpar to f thebird swinterin g ino rpassin g throughth eBan cd'Arguin ,i so f Icelandico rNearcti corigin .Th eBalti crecover y suggests thatals o populationsfro mnorther nScandinavi ao rth eUSS Rar einvolved .Th e origino fth elon gbille dbirds ,however ,fo rth emomen t remainsobscure . Evenmor ei suncertai nregardin g the juvenilebirds .Autum ncatche sa t CapTimiri s (Dick 1975)sugges ta nexodu so fRinge d Plovers,particularl y juveniles,t owinterin gquarter sfurthe rsouth .

~~~~.»49 —*a»>^s~~~~

4 KentishPlove r *~^r 'CorJ .Smi t 4.1 Introduction KentishPlover sar e relatively uncommona t theBan cd'Arguin .Altenbur g etal .(1982 )arrive da tsomewha tove r 17,000bird sfo rth ewhol earea , whichi s0.8 %o fth etota lnumbe ro fwader swinterin g inth earea .Thes e birdsar emainl y feedingo nmuddin gan d sandyseagras san dmudd yAre a flats.I nth ebes tarea sdensitie sa tlo wtid ear eu pt o2 bird spe rha . (Altenburge tal . 1982).Number scounte d inth eBal ed'Aouati fshowe da steadydecline ,fro m 1400o n2 4Marc h 1985t o45 0o n2 5April .Number si n EbelkAizna iwer erathe rsmal lan dd ono tallo wan yconclusion s(cf . Rappoldt etal . 1985)o nchange s innumbers .

~~~~Table 4.1. Bodymeasurement s(i nmm )o fKentis hPlover scapture da t theBan cd'Argui ni nFebruary-Apri l 1985an d1986 .~~~~

~~~~2ndc.y . Adult Allbird s average+ S.D . average+ S.D . average+ S.D . range,numbe r range,numbe r range,numbe r~~~~

~~~~Winglengt h 112.5+3.7 111.9+3.4 112.1+4.2 107-119;n=1 3 105-116;n= 9 102-119;n=2 4~~~~

~~~~Billlengt h 15.7+1.0 15.6+0.4 15.8+0.9 14.2-17.3;n=1 3 14.8-16.2;n- 9 14.2-17.3;n=2 4~~~~

~~~~Totalhea dlengt h 42.9+ 1.3 42.4+ 0. 6 42.8+ 1.2 40.8-45.5;n=1 3 41.6-43.3;n- 9 40.8-45.5;n=2 4~~~~

~~~~Tarsus+ to e 48.5+ 1.6 48.1+ 2. 2 48.3+ 1.8 46-51;n=1 3 43-51;n= 9 43-51;n=2 4~~~~

250 4.2Catche s Allbu ton ebir dwer ecapture d inmis tnet so nvariou scatchin gsites . Thetota lnumbe ro fKentis hPlover scapture d in198 5an d 1986amount st o 24birds ,59 %o fthes ebein gsecon dcalenda ryea rbirds .Thi sfigur ei s quiteclos e toth e65 %foun db yDic k (1975)a tth eBan cd'Argui n in197 3 andb yVa nDij ke tal .(1986 )i nth eGul fo fGabès ,Tunisia .Nin ebird s weresexe da smales ,on ea sa femal ebu ti tshoul db ekep t inmin dtha t malesca nb emor eeasil y sexed (Prater etal . 1977).Tw obird scoul dno t beage d successfully.Al lbird swer enewl yringed .N oretrap s (ownbirds ) orcontrol s (foreignbirds )wer eobtained .

~~~~4.3Biometric s Bodymeasurement s ofKentis hPlove rcapture d in198 5an d 1986ar egive n~~~~

Table 4.2. Biometrics (x+ S.D. )o fjuvenil ean d secondcalenda ryea ran d adultKentis hPlover salon gth enort han dwes tAfrica ncoast .Dat awer etake n fromDic k (1975)(5) ,Pienkowsk i (1975)(1) ,Mose r (1981)(2) ,Kerste ne tal . (1983)(3) ,Va nDij ke tal .(1986 )(4 )an dthi sstud y(6) .

~~~~Origin Winglengt h(mm ) Billlengt h(mm )~~~~

~~~~juveniles adults juveniles adults + 2ndc.y . + 2ndc.y .~~~~

~~~~1 Morocco 110.7+ 3.1 109.3+ 2.9 14.9+ 0.8 14.9+ 3.3 autumn 1972 (n-15) (n-34) (n-17) (n-69)~~~~

~~~~2Sid iMoussa ,Morocc o 109.9+3.8 110.4+3.0 14.7+0.6 15.1+1.1 autumn 1980 (n-29) (n»14) (n=35) (n=29)~~~~

~~~~3Sid iMoussa , Morocco 112.0+ 2.5 114.8+ 1.6 15.5+ 0.5 15.4+ 0.7 spring198 1 (n-6) (n=7) (n=6) (n=7)~~~~

~~~~4Gul fo fGabè s ,Tunisi a 113.8+ 2.8 113.8+ 2.5 16.0+ 0.8 15.7+ 0. 6 winter198 4 (n=33) (n-11) (n=33) (n=ll)~~~~

~~~~5Ban cd'Argui n 110.8+ 2.7 110.8+ 0.6 15.5+ 0.8 15.3+ 1.2 autumn197 3 (n=ll) (n=6) (n-11) (n-6)~~~~

~~~~6Ban cd'Argui n 112.5+ 3.7 111.9+ 3.4 15.7+ 1.0 15.6+ 0. 4 spring1985 , 1986 (n=13) (n=9) (n=13) (n=9)~~~~

251 intabl e4.1 .Win gan d billlength so fbot hsecon d calendaryea ran d adult birdsar esomewha t largera scompare d to 1973value s (Table 4.2) butsampl esize sar e smallan dnon eo fthes edifference s isstatisticall y significant.Tabl e4. 3 showstha tonl yfe wbiometrica lparameter sar e significantly correlated.Ther eappear s tob ea stron gcorrelatio n (p<0.001)fo rbil lan d totalhea d length.I ngenera lcorrelation sar e muchlowe ra scompare d toth esurprisingl yhig hone sfoun din ,fo r instance,Sanderlin gan dTurnstone .

4.4Weight s Hardlyn oinformatio nwa scollecte d onweigh tlos sbetwee ncatchin gan d weighing.Therefor eresult so fth eSid iMouss a 1981expeditio n (Kersten etal .1983 )wer euse d showing that theaverag eweigh t losso ffou r (!)

Table 4.3. Correlation coefficients of corrected weight and biometrics of Kentish Plovers (all age classes), n=24. Coefficients significant at the 0.05 level are marked with *, those at the 0.01 level with **an d those at the 0.001 level with ***

~~~~Weight Wing Bill Total head length length length~~~~

~~~~Wing length 0.5149** Bill length 0.0718 0.2618 Total head length 0.2984 0.4355* 0.7459*** Tarsus + toe 0.1004 0.0575 0.2379 0.2337~~~~

~~~~Table 4.4. Corrected meanweight s (grams)o f second calendar year and adult Kentish Plovers captured at the Banc d'Arguin in February-April 1985/86.~~~~

~~~~Month 2nd c.y. Adult average + S.D. average + S.D. range, number range, number~~~~

~~~~February 34 (n=l) 38 (n=l)~~~~

~~~~March 41.4+ 8.0 42.0+ 4.9 35-38; n=7 36-46; n=4~~~~

April 40.8+ 7.5 43.0 + 2.6 33-51; n=4 40-46; n=4 KentishPlover s amounted to0. 3 g/h.Th eresult spresente d herehav ebee n corrected accordingly.O naverag eKentis hPlover swer ekep t 3.22h + S.D . 1.82 (n=23)betwee ncatchin gan dweighing .Th eresult so fou r measurementsar eshow ni ntabl e 4.4.Adul tweight s tend toincreas ever y slightly inth ecours eo fth eseaso nbu tthi sdoe sno tappl yfo ryoun g birds.Th elimite damoun to fdata ,however ,doe sno tallo wan yfurthe r analyses.Bot hsecon dcalenda ryea ran dadul tweight sar eslightl y exceeding thelevel sfoun d byDic k (1975). Thelatte rdat a (September-November 1973)sho wa mea n juvenileweigh t of36. 5g + S.E . 1.2 (n=ll)an da mea nadul tweigh t of38. 7g + S.E .1. 8 (n=6).Secon d calendaryea ran dadul tTunisia ncapture dbird s (January-March 1984) weighed 41.3g o naverag e (VanDij ke tal .1986) ,Morocca nbird s (March 1981)wer elighte r (36.5g an d 37.3g resp. )(Kerste ne tal .1983) .Thi s indicates thatalthoug how nMauritania n springweight swer elow ,ther ei s acertai ntendenc y tofatte nup .Figur e 9.4.1,however ,show stha tn o obviousweigh t increase inth ecours eo fth esprin gca nb edetected .Thi s appliesbot hfo ryoun gan d foradul tbirds .Onl y twobird sou to f2 2use d fordat aanalysis ,weighin g 51g an d 58g respectively ,wer eobviousl y heaviera scompare d toth erest .Assumin ga lea nweigh to f4 0g th e heaviestbir d carried 18g fat .Applyin g theequatio ngive nb yDavidso n (1983)thi sbir dwoul db ecapabl eo fcoverin ga non-sto p flighto f somewhatles s than200 0km . KentishPlover sleav e theirwinterin g quartersrathe rearl y inth e season.Breedin g sitesi nsouther nMorocc oar ereoccupie d from theen do f Februaryonward s (Robini nGlut zvo nBlotzhei met .a l 1975).Furthe r north (Bretagne)Kentis hPlover sarriv e relatively earlya swell ,i.e . fromearl yMarc hon .Th emajorit y ofth epopulatio ni nthi sare aarrive s inth esecon d parto fMarc han d inth ecours eo fApril .Territorie si n countriesborderin g theNort h Seaar ereoccupie d fromth een d ofMarc h untilmid-Apri l (Glutzvo nBlotzhei me tal . 1975).Number salon gth e Moroccancoas t (SidiMoussa )decrease d inth eearl ypar to fMarc han d wererathe rstabl ei nth efollowin gweek s (Kerstene tal . 1983). Considering thesedat aan dkeepin g inmin d that onlyfe wadul tKentis h Ploverswer erelativel yheav yw emus tconclud e thatmos t ofth ecapture d birdsprobabl ywer eno t preparinga lon gdistanc e flight towardsbreedin g areasi nEurop eo rnorther nAfrica .Unfortunatel y onlyver yfe wKentis h Ploverswer ecapture d inth ecours eo fFebruar yan dMarch .Th e fewdat a available forthi sperio d dono tallo wan y speculations ondepartur e weightsan dmigratio nstrategies .

~~~~253 WEöwr, a~~~~

~~~~6o - o 66 -~~~~

~~~~52 o~~~~

~~~~«« - • • • • <* O o • «O o» §• • o J6 o • 0 o i ! 1 1 1 1 1 1CV2 2oa vui KV3 *>* 31/3~~~~

4.5 Plumage Adult Kentish Plovers captured at the Banc d'Arguin tended have an intermediate plumage inMarch . ByApri l all captured birds were in summer plumage but the number of birds this applies for is limited. According to Cramp & Simmons (1983)adul t Kentish Plovers come into breeding plumage from November to early December onwards,o r even earlier than that.Ful l breeding plumage isattaine d by January-early March. Second calendar year Kentish Plovers tend toge t into summer plumage from earlyMarc h onwards but by mid-April,whe n several birds are in full summer plumage, some others still carry almost complete winter plumage. Possibly part of the latter birds remain in the area to spend the summer. There is no obvious correlation between the amount of summer plumage and the presence of body moult.Bird s in full winter plumage could be in moult or show no sign of body moult at all,th e same applied for intermediate plumages.Mos t birds showing body moult,adult s aswel l as younger ones, did so at a rather low level.Non e of themwa s in full body moult or showed primary moult.

~~~~254 piMMAftE-~~~~

~~~~o o o o~~~~

~~~~«M2 2G& 25/2 -IO/3 20/3 ^1/3 iOM 20M~~~~

~~~~Figure .4.2 . Plumage of Kentish Plover at the Banc d'Arguin in February-April 1985/86.Ope n circles refer to second calendar year birds, dots toadults .~~~~

4.6 Geographicalorigi nan dmigratio n Thoughrathe rfe wdat aar eavailable ,th efrequenc ydistributio n ofbil l lengthso fMauritania ncapture d KentishPlover sha sa singl epeake d shape.Mos t billsmeasure d between 15-16mm .Thi si si ncontras twit h datafro mTunisia .Va nDij ke tal .(1986 )foun da bimoda ldistributio n withpeak si nth e 15-16m man d 17-18m mrange .Win g lengthsa tth eBan c d'Arguin showeda tendenc y towards twopeaks ,on ebetwee n 105-110cm ,an d onebetwee n 112-117cm .I nTunisi amor eo rles sth esam edistributio nwa s found.Usin g thePCF-metho d outlined byGriffith s (1968), 60%o fth e Tunisianbird sappeare d tob esmall-winge d (mean 111.7m m+ 1.7),40 %wa s larger-winged (mean 116.3m m+ 0.9).Par to fth eTunisia npopulatio ni s thought tob eresidental ,anothe r parti sbelieve d tooriginat efro m southernFranc ean dpossibl y from Italyan d thecentra lpar t ofEurope . According toCram p& Simmon s (1983)northwes tEuropea nKentis hPlover s havewing so f 113m m (males)t o 114m m (females)(mea ndat acorrecte d for shrinkage,Engelmoe re tal . 1983), thoseo fth eCanar y Islandsan d Maghrebcountrie s beingapproximatel y 1m msmaller .Measurement s ofwing , tailan d toeapparentl ydecreas egraduall y fromwester nt osouther n Europewherea smale so fsouther nbreedin g populationsmor e often tendt o havea brigh tcinnamo ncoloure d crown.Th elatte r phenomenon definitely

255 hasbee nfoun d inou rcatches .Measurement s ofBan cd'Argui ncapture d KentishPlover sar ei nrathe rgoo dagreemen twit h thelonger-winge d bird innorthwes t Europebu td ono tgiv ea nobviou sclu eo nth eorigi no fth e fewshort-winge d birds.Neithe rd oth erelativel y long-winged Tunisian birdsfi tint othi spicture .Short-winge d KentishPlover shav eals obee n found inMorocc o inautum n (Table 4.2).Durin g springmigration ,however , themea nwin g lengthappeare d tob e 4m mlarger .Par to fthi sdifferenc e mayb eexplaine d byfeathe rabrasio no fadul tbird swhic hha dno tmoulte d yet inautumn ,bu ti ti sunlikel y thatthi sexplain sal lo fth e difference.Possibl ydifferen t populations ofdifferen tbreedin garea s areinvolved .Correspondin g toth eMorocca nautum ncatche smea nwin g lengthsa tth eBan cd'Argui n aresomewha t smallera scompare d towester n Europeanbreedin g birds.Par to fth eexplanatio nfo rthi sphenomeno nma y betha tth ebreedin g population,whic h issuppose d towinte ri n Mauritania,largel yconsist so fsouther nEuropea nbirds .Piersm a (1986) estimates theEuropea npopulatio no fKentis hPlover sa t6400-960 0pairs . Most ofthes ear ebreedin g inSpai n(2000-3000 )an dPortuga l (1500-3000). Smallernumber sar efoun d furthernorth ,Franc ean d theWadde nSe a countriesholdin ga populatio no f 2650-3100pairs .Th esiz eo fth e Moroccanbreedin gpopulatio n isno tknown ,th eon efro mth eBan c d'Arguin itself isthough t toamoun t toonl y3 0pair s(Trotigno ni nCram p& Simmons 1983).Th eEuropean/Nort hAfrica nbreedin g populationi sbelieve d todistribut eove r theEas tAtlanti ccoas tan dwester npar to fth e Mediterranean (Cramp& Simmon s 1983,Smi t& Piersma ,i nprep.) .Thes e datalea d toth econclusio n thatMauritania ncapture dKentis hPlover sar e amixtur eo fwestern ,souther nEurop ean d probablyNorthwes tAfrica n breeding places,probabl ymigratin g indistinc twaves .Th eorigi no fth e small (105-110mm )winge d birdsremain sobscure .

256 5 Grey Plover Cor J. Smit 5.1 Introduction Ascompare d tosom eothe rwade r speciesGre yPlover sar erathe r scarcea t theBan cd'Arguin .Altenbur ge tal .(1982 )arrive d at 23,500bird sfo r thewhol earea ,abou t 10%o fthes ewinterin g inth eBai ed'Aouatif .Th e numbero fGre yPlover si nth ewhol eare acorrespond s toabou t 1%o fth e totalnumbe ro fwaders .Gre yPlover sca nb efoun di nsevera lhabita t typesfeedin g indensitie srangin gfro mles stha n 1u pt o3 birds/h a (Altenburge tal .1982) .Number si nth eBai ed'Aouati f in198 5varie d between 1253an d 1921birds ,showin gn oobviou s trend todecreas eo rt o increase.Th esam eapplie d fornumber scounte d inEbel kAiznai .

5.2Catche s Thetota lnumbe ro fGre yPlover scapture d in198 5an d 1986amount s to2 2 birds;fiv ebird swer ecapture d usinga cla pnet ,on eusin ga canno nnet , theremainin g 16i nmis tnet sa tvariou splace si nth eBai ed'Aouatif . Allbird scoul db eage d successfully.Exactl yhal f thenumbe rwer esecon d calendaryea rbirds .Thi si sconsiderabl ymor etha nth e19 %foun db yDic k (1975).I tshoul db ekep ti nmind ,however ,tha tth enumbe ro fbird s captured in197 3wa ssmal lto oan damounte d toonl y2 1birds .Al lbu ton e bird,capture d in 1985/86,wer enewl yringed .On esecon dcalenda ryea r bird,capture d on2 2Marc h 1985,wa sretrappe d asa nadul to n1 Marc h 1986. Biometricso fth elatte rbir dar eshow ni ntabl e5.1 .

~~~~Table 5.1. Blometrical data of aGre y Plover (FT 92002)capture d both in 1985an d 1986.~~~~

~~~~Date Age Corrected Wing Bill Total Tarsus weight head + toe~~~~

~~~~22Marc h 1985 2nd c.y. 203 203 319 691 83 1Marc h 1986 adult 201 209 323 705 82~~~~

257 5.3 Biometrics Bodymeasurement s ofGre yPlover scapture d in198 5an d 1986ar egive ni n table 5.2.Win gan d billlength so f juvenilescanno tb ecompare dwit h results from 1973becaus e inth elatte ryea ronl y 4juvenil ebird swer e captured.Th esam eapplie sfo radul twin g lengths,whic hha d tob e splitted upi n197 3becaus e somebird scarrie d oldan dabrase d primaries whereasother sha dne wones .Bil llength so fadul tGre yPlover si n197 3 were significantlylonge ra scompare d to1985/8 6(t=2.64 ,p<0.01) . Furtherdetail so nthi smatte rca nb efoun di nchapte r5.6 .Tabl e5.3 . showstha tespeciall y totalhea dan dbil llength so fGre yPlover sar e highlycorrelated .Th esam eapplie sfo rcorrelation so ftarsu s+ to ewit h billan dtota lhea dlength .

~~~~Table 5.2. Body measurements (mm)o f Grey Plovers captured at the Banc d'Arguln inFebruary-Apri l 1985an d 1986.~~~~

~~~~2nd c.y. Adult All birds Average + S.D. Average + S.D. Average + S.D. range, number range, number range, number~~~~

~~~~Wing length 197.3+ 3.7 202.4+ 5.1 199.8+ 5.1 192-203,n=l l 195-210,n=l l 192-210,n«2 2~~~~

~~~~Bill length 30.6+0.8 29.8+1.8 30.2+1.4 29.3-31.9,n-1 1 26.7-32.3,n-1 1 26.7-32.3,n=2 2~~~~

~~~~Total head length 68.4+ 0.9 67.8+ 2.2 68.1+ 1.7 67.1-70.5, n-11 64.0-71.0,n=l l 64.0-71.0,n=2 2~~~~

~~~~Tarsus+ toe 82.4+ 1.0 81.1+ 3.6 81.7+ 2.7 81-85,n=l l 75-87,n=l l 75-87, n-22~~~~

Table 5.3. Correlation coefficients of corrected weight and biometrics of Grey Plovers (all age classes), n-22.Coefficient s significant at the 0.05 level aremarke d with *, those at the 0.01 level with **an d those at the 0.001 level with ***.

~~~~Weight Wing Bill Totalhea d length length length~~~~

Wing length 0.4142* Bill length 0.0788 0.3232 Total head length 0.0801 0.4263* 0.8213*** Tarsus + toe -0.0136 0.3238 0.5615** 0.5922**

258 5.4Weight s Noinformatio nwa scollecte d onweigh t lossbetwee n catchingan d weighing.Base d onth eresult so f the 1981Sid iMouss aexpeditio n (Kerstene tal .1983 )weigh t losswa sassume d toamoun t tob e 1.5g/h . Theresult spresente d herehav ebee ncorrecte d foraccordingly .Gre y Ploverswer ekep t 2.77h + S.D .2.2 0 (n=22)o naverag ebetwee ncatchin g

~~~~Table 5.4. Corrected mean weights (grams) of second calendar year and adult Grey Plovers captured at the Banc d'Arguin In February-April 1985 and 1986.~~~~

~~~~Month 2nd c.y. Adult Average + S.D. Average + S.D. range, number range, number~~~~

~~~~February 187 (n-1)~~~~

~~~~March 184.7 + 16.2 202.2 + 12.0 164-207, n-7 188-221, n-5~~~~

~~~~April 185.3 + 12.9 209.8 + 29.3 176-200, n=3 163-238, n=6~~~~

~~~~WE.16UT, <3~~~~

~~~~mo • •~~~~

~~~~• 72X> •~~~~

~~~~• o o 200 o • • • • o J •o 480 o o o o iéo o •~~~~

~~~~i 1 1 8 2S T=ee> MA«. ASO.~~~~

Figure 5.1. Weights (grams) of Grey Plovers captured at the Banc d'Arguin in February-April 1985/86. Open circles refer to second calendar year birds, dots to adults. Weights have been corrected for weight loss between catching and weighing.

259 andweighing .Th eresult so fweigh tmeasurement sar epresente d intabl e 5.4. Theseresult sd ono t showa weigh t increase forjuvenil ebird san da rathersligh ton efo radul tbirds .Figur e 5.1 showstha tfro mmid-Marc h onwards someadult s increasei nweigh twherea sother sd ono t showan y signa tall .Th eheavies tbir dmeasure dha da weigh to f23 8g o n2 3 April,whic hi sver ylo wa scompare d toMa yweight so nth eWas h (mean 316.9g ;Johnso n 1985).Assumin ga lea nweigh to f 196g (calculatedfro m equationsi nDavidso n 1983),a 4 2g fa t loadwoul d carrymigratin gGre y Ploversa sfa ra sove r 2000k m(Davidso n 1984).Thi swoul dbrin g thema s farnort ha sth eMorocca ncoast ,a distanc ecomparabl et oth eon efoun d insom eothe rspecies .

5.5Plumag e Onlyhal f ofth eGre yPlover scapture da t theBan cd'Argui n showedsign s ofsumme rplumage .Fro mearl yMarc honward sespeciall yadul tbird sstar t comingint osumme rplumag e (Fig.5.2) ,thoug hno tal lo fthe mreall yd o so. Funnyenoug hfigur e 5.3show stha tmos tGre yPlover s startthei r activebod ymoul ta slat ea sth een do fMarch .Sinc esom ebird sb ythi s timealread ycarr ya plumag eintermediat e tosumme ran dwinte rplumage , bodymoul tmus thav e started earlier thansuggeste d byfigur e 5.2.Ther e

~~~~KUMA.&E.~~~~

~~~~4.0 - • •~~~~

~~~~3.0 o • • • o~~~~

~~~~2.0 o • ••~~~~

~~~~•i.0 O • o8° o • 1 oo • 1 25 T=EB MAR Mf3~~~~

~~~~Figure 5.2. Plumage of Grey Plovers at the Banc d'Arguin in February-April 1985/86.Ope n circles refer to second calendar year birds, dots toadults .~~~~

260 have beenn o captures of birds inplumag e stages 5-7,i.e . close to complete summer plumage.Fiel d observations,however , showed that some birds apparently do come into full summer plumage at the Banc d'Arguin. By mid-April most Grey Plovers,bot h adult and second calendar year birds,hav e been found in intermediate or heavy bodymoult .Thi s finding suggest that most Grey Plovers continue their body moult while on migration towards the breeding areas. Grey Plovers at the Banc d'Arguin showed no signs of primary or secondary moult.Thi s finding is in strong contrast with observations in Tunesia where inMarc h 1984 9ou t of 40Gre y Plovers showed primary moult and 22ou t of 40showe d secondarymoul t (VanDij k et al. 1986).

~~~~aoDv Moacr HEAVY 3 o •~~~~

~~~~INTERn 1 ••o •o~~~~

~~~~LIGHT \~~~~

5.6 Geographical origin and migration Grey Plovers migrating through Northwest-Europe are believed to originate from theWest-Siberia n population, though a recovery from the Taymyr peninsula indicates that also Central-Siberian birds are present (Cramp & Simmons 1983). Recoveries from Great Britain show that the winter quarters of birds passing through Northwest-Europe are situated as far south as Ghana (Spencer & Hudson 1978). Figure 5.4 shows the results of thewin g length-bill length relation of Grey Plovers captured at the Banc d'Arguin in 1985-86.Thi s graph also shows the means and standard

261 deviations of three populations of Grey Plovers,base d on data supplied by Engelmoer (1984). Using discriminant analyses he concludes that the following populations of Grey Plovers can be distinguished: 1.a short-winged population breeding in the Northeast of Canada,whic h also has been found onmigratio n in Greenland; 2. a short-billed and long-winged population breeding in West-Siberia which also has been found onmigratio n inNorth-Europe ; 3.a long-billed and long-winged population breeding in Central and East-Siberia and Alaska.

According to Engelmoer (1984)al l three populations are present in Northwest-Europe, 76%o f the birds belonging to the Westpalearctic population, 14%t o the Eastpalearctic population and 10%t o the Canadian population. Though the number of captures is small the Mauritanian findings point in the same direction,mos t of the birds having intermediate wing and bill lengths,som e extremes being on the edge of

~~~~1 ME CANA.DA, GteEENUAJvlD (0*33) 3 ALASKA. CEXTRALt E .SI&ER.ÏA. ^=63}~~~~

~~~~2 N. ExiRope, w. SIBEQAA. £n» 13) e>iLL LENGTH~~~~

~~~~34 -~~~~

~~~~• 3X - 0 • • O 0 0 O 0 —0—-• - 0 • —c »— e 30 O I • 0 -CO- 0 t • iY~~~~

~~~~• • 26~~~~

~~~~en i I I i I 190 i<3S 20O 205 210 WINKS i_eNGm~~~~

Figure 5.4. Wing length- bil l length relationo f GreyPlover scapture d at theBan cd'Argui nan dmea n lengthsan d standarddeviation so fGre y Plovers populationselsewher e (based onmuseu m skins, corrected from shrinkage; Engelmoere t al. 1983). Opencircle s refer to secondcalenda r birds, dots to adults.

26: whatha sbee nmeasure d onWestsiberia nbirds .Th elatte rmeasurements , especiallysom ever ylong-winge d andlong-bille d birds,sugges t thata t least somebird sfro measter nPalearcti cpopulation sar epresen ta tth e Bancd'Argui nan dpossibl yals obird sfro mth eNearcti c population(th e presenceo fth elatte rpopulation ,however ,ha sno tye tbee nconfirme d through ringrecoverie s inwester nEurop eo rwester nAfrica) .Th efac t thatautum ncatche s (Dick 1975)yielde deve nlonger-bille d birds (chapter 5.3)suggest stha tthes ebird sar eeve nmor enumerou si nthi sseason .A possibleexplanatio nma yb etha t therelativel yhig hnumbe ro fGre y Ploverswhic hha sbee nfoun d towinte ri nGuine aBissa u (57,000;Zwart s 1988)an dfurthe r southalon gth eGul fo fGuine aconsist so fa relativel y highproportio no feaster nPalearcti cbirds .A nanalyse so fbiometric so f GreyPlover scapture d inGuine aBissa ushow stha ta hig hproportio n actuallydoe sconsis to flarg ebille dEaster nPalearcti c birds (Altenburg etal. ,i nprep.) .

263 TheunisPiersm a 6 Knot (Calidriscanutus ) 6.1 Agerati o Therati obetwee nKnot si nth ecatche sage da sjuvenile so ra sadults , appeared tovar yconsiderably ,bot hwithi nan dbetwee n theyear s 1985an d 1986(Tabl e6.1) .I nbot hyear sther ei sa tren d ofth ejuvenil e percentagesbecomin g smalleri nth ecours eo fth esprin g season.Th e percentageo f juvenileswa sgenerall yhighe ri n 1986tha ni n1985 . Catching studiesi nautum n 1973b yDic k (1975)hav eindicate d that juvenilesar emor elikel y tob ecaugh ti nmis tnet stha nadults ,compare d tocanno nne tcatches .Thi smean stha tth epercentage so f juvenilesi n our (mistnet )catche sma yoverestimat e therea ljuvenil epercentages .

~~~~Table 6.1. Juvenile adult ratios of Knots captured on the Banc d'Arguin in the springs of 1985an d 1986.~~~~

~~~~Period Sprin g season 1985 Sprin g season 1986 n juv. n ad. % juv. n juv. n ad. % juv.~~~~

~~~~8-28 February - - - 36 5 88 1-15 March - - - 23 6 79 16-31 March 12 25 32 - - - 1-14 April 11 106 9 18 2- 43 — 15-25 April 16 116 12 - —~~~~

6.2 Biometrics Table 6.2.show s theaverage so f thebod ymeasurement so fKnots . Juvenileshav e shorterwing san dlowe rbod ymasse s thanadults ,bu tth e otherbod ydimension swer eslightl y largeri njuveniles . Theaverag eadul tbil llengt ho f 35.1m m indicates thatw ear edealin g withbird so fth eSiberia nbreedin g populationCalidri scanutu scanutu s

264 Table J 6.2. Body measurements of Knots captured on the Banc d'Arguin in February-April 1985/86.Bod y mass was corrected for loss after capture. The number of juveniles in the sample is 116,th enumbe r of adults 278 (wing, tarsus + toe),o r 281 (rest).

~~~~Measurements Juveniles Adults Average S.D. Average S.D.~~~~

Wing length (mm) 163.89 4.13 169.71 3.90 Bill length (mm) 35.62 1.82 35.12 1.78 Total head length (mm) 64.32 2.04 64.00 1.96 Tarsus + toe length (mm) 59.36 1.86 58.95 1.81 Body mass (g) 119.20 10.03 144.2 15.42

(Dick,e tal . 1976,1987) .Th elinea rbod ymeasurement s ofKnot scorrelat e strongly (Table6.3) .I tcome sa sn osurpris etha ttota lhea dlengt han d billlengt hsho wth estronges tcorrelatio nwit heac hother .

6.3 Bodymas schange s Bodymas s isa complicate dmeasur ebecaus ei ti ss ovariable .I tdepend s onwate ran dfoo dintak ean dexcretion ,s otha tbird sloos emas safte r capture.W etherefor ehav e totransfor mbod ymasse s takena tvariou s intervalsafte rcaptur e toth etim eo fcapture ,takin g intoaccoun tth e post-capture lossi nbod ymas s (Goede& Nieboe r 1983,Davidso n 1984a). Figure6. 1 showstha tKnot slos to naverag e0. 8g/ h betweenfirs tan d secondweighing ,i.e .afte rth eperio d ofrapi dmas s lossi nth efirs t fewhour safte rcapture .Figur e 6.1 alsoshow stha t 'our'Knot swer e weighedbetwee n 1an d8 hour safte rcapture .I nthi sstud yal lbod ymas s

Table 9-6.3.Pearso n correlation coefficients between different body measurements of adult Knots on the Banc d'Arguin in 1985an d 1986.Al l correlation coefficients are significantly different from zero at the 0.1%level .

~~~~Bill Total head Tarsus + toe~~~~

~~~~Wing 0.334 0.356 0.390 Bill 0.821 0.334 Total head 0.337~~~~

~~~~265 HASS DlfPEREMCE BETWEEN FIRST AMD SGOOND WEK»M»JG,G~~~~

~~~~O 1 L__^^H i 1 1 1 1 1 1 4 2 4 6 S -IO 12 MOOR TINE BETWEEN CAJTUQE. >*4D FlRSf VOElfiwUMÇ,~~~~

Figure 6.1.Mas s loss after capture byKnot s onth eBan c d'Arguini n 1985 and 1986,an dweighe d twice after capture (A).B show s howlon gi t took between capture andfirs t weighing foral lcapture d Knots: black indicates juveniles, white indicates adults (n= 395) . valueshav etherefor ebee ncorrecte dt orepresen tth e(theoretical )bod y massa tth etim eo fcaptur e (adding0. 8 g/h).

6.3.1 Juveniles. Sincether ewer en oobviou sdifference sbetwee nth e bodymasse so fjuvenil ebird scaugh ti n198 5an d1986 ,th edat afro mth e twospring swer etake ntogether .Tabl e 6.4.present sth eaverag ebod y masseso fjuvenile si nth ecours eo fth espring ,a sderive d fromth e completedat aset ,whic hi sshow ni nfigur e6.2 .Th etendenc yo faverag e bodymas st odecreas ei nth ecours eo fsprin gi sdu et oth eabsenc eo f anyheav y (135-160g )juvenile safte r1 0April .Th edecreasin g percentageso fjuvenile sdurin g spring (Table6.1 )an dth eabsenc eo f

~~~~266 KIUMSER OF &~~~~

~~~~6 RW~~~~

~~~~2 O IJ 6 1 — 15 M«C*-< 4 S o f~ —1 1—I~~~~

~~~~A 16- 3\ MBCH 2 o I" ~1~~~~

~~~~4 i-a A*«.~~~~

~~~~2 o I n 6 IO- IM Af>R~~~~

~~~~IO - V5 /M>K ^ - 2 . r~ i > i I i •WO 1 10 iiZ O U JO ^3DY HAß», «~~~~

Figure 6.2.Variatio n inbod y mass of juvenile Knots onth eBan c d'Arguin inFebruary-Apri l 1985/86. juvenilesheavie r than13 0g afte r 10Apri lma yindicat ea nearl y departureo fKnot sfro mth eBan cd'Arguin .Sinc ei ti sclea r thatsecon d calendaryea rbird sd ono tpu to nfa ti nApri lt odepar twit hth eadult s toth enort hi nlat eApril/earl yMay ,i ti spossibl e that therear eearl y leaving juvenileswh og osouthward se.g .t opossibl esummerin garea si n Guinea-Bissau.Thi shypothesi sclearl yneed stesting .

6.3.2 Adults. Bodymasse so fadul tKnot s showa larg evariation ,eve n withinperiod san despeciall y fromApri lonward s (Fig.6.3) .Par to fthi s variationma yb edu et ovariation si nstructura l size,a si sindicate db y thepositiv ecorrelation sbetwee nmas san dvariou sbod ydimensions , especially billan dtota lhea d length (Table 6.5).Ther ewer en o

~~~~267 NUMBER OF ADULT KNOTS 1 28 PEA o! r^i m -15 MRftM i n r^—i j—i m! si- -3\ M«*>i ! m t-* J r-t~~~~

~~~~1'OO-HO 120 130 WO\SO 160f ?0 1ÖO19 0 BODY MAS6, G~~~~

Figure 6.3. Body mass changes of adult Knots on the Banc d'Arguln in the springs of 1985/86.Th e shading refers tobird s presumed to b#long to one 'migratory cohort'. Open areas indicate a group which may include lighter and later arriving birds,an d excludes some early leaving,heav y ones.

Table 6.4. Body mass (g)o f juvenile (second calendar-year)Knot s on the Banc d'Arguin in the springs of 1985an d 1986.Sinc e there were no detectable differences between the two years,th e data were taken together. Bodymas s was corrected for loss after capture.

~~~~Period Average S.D. (n) Minimum Maximum~~~~

8-18 February 120.5 10.4 (36) 102.2 117.0 1-15 March 120.1 11.5 (23) 103.6 150.6 16-31 March 123.0 10.7 (12) 108.2 138.0 1- 9 April 119.8 10.0 (16) 106.1 142.2 10-14 April 112.3 6.1 (13) 98.5 118.8 15-19 April 117.6 6.3 (14) 109.0 129.4 20-25 April 113.5 13.3 ( 2) 104.1 123.0

~~~~Total 119.2 10.0 (116)~~~~

~~~~268 BOOV MASS, CM~~~~

~~~~18»O~~~~

~~~~FEBRUARY MARCH APRIL~~~~

Figure 6.4.Averag e increase inbod y mass of adult Knots on the Banc d'Arguin in the springs of 1985/86.Th e thin line describes the linear 2 2 regression through all data points (r =0.43)an d the thick line (r =0.21) excludes the data from the last period and the birds with low body masses from the period 15-19 April (white area in figure 9.6.3). The dots give averages + 95%confidenc e intervals.

Table 6.5. Pearson correlation coefficients between different structural size variables and body mass of adult Knots on the Banc d'Arguin in different periods in the springs of 1985an d 1986.Singl e underlined values are significant at the 5% level and bold typed values at the 0.5% level. The remaining correlation coefficients are not statistically significantly different from zero.

~~~~8-28 Feb 1-15 Mar 16Mar - 10-19Ap r 20-25 Apr 9 Apr (n-5) (n-6) (n=94-96) (n-131-132) (n=40)~~~~

~~~~Wing 0.378 0.281 0.303 0.457 0.594 Bill -0.491 0.776 0.372 0.512 0.406 Total head -0.525 0.700 0.350 0.519 0.427 Tarsus + toe 0.557 0.537 0.251 0.375 0.323~~~~

~~~~269 KianaER or &Rr>s~~~~

~~~~-3 o 1 2 3~~~~

Figure 6.5. Discriminant scores of adults Knots caught on the Banc d'Arguin in the springs of 1985/86,base d on the discriminant formula derived by M. Engelmoer frommeasurement s of sexed museum skins of Siberian Knots: Discriminant Score = (0.1851333 *WING )+ (0.4909321 * BILL)- 49.21633.Win g and bill inmm .

differencesbetwee nth etw oyears .Averag ebod ymas sincrease d linearly fromFebruar y onwards,bu tshowe da smal ldeclin ei nlat eApril .Thi s declinei slikel y tob edu et oth earriva lo fligh tbird so npassage , probably comingfro mth esouth ,an db ydepartur e ofsom eo fth eheavies t birds.Thi si sindicate d byth e 'new'ligh tbird swhic hsho wu pi nth e overalldiagra mfo rth eperio d 15-19Apri lan dth eobviou slos so fman y ofth eheavies tbird s (Fig.6.3) .Thi scoincide swit ha decreas ei nth e extent ofsumme r plumageo fadult sbird scaugh ti nth elas t twoperiod s (below,Fig .6.8.) .A linea rregressio nlin ethroug hal lavailabl edat a pointsyield sa nestimate d bodymas sincreas eo f0.47 6g/da y (Fig.6.4.) . Ifw eleav eou tth elightes t birdsfro mth eperio d 15-19Apri lan dal l datapoint s from20-2 5Apri l (Fig.6.3 : theunshade d part),w earriv ea t anestimate daverag ebod ymas sincreas eo f0.56 1 g/day (Fig.6.4.) . Thepositiv e correlationsbetwee nbod ymas san dlinea rmeasurement s (Table6.4 )indicate s thatpar to fth ebod ymas svariation sma yb edu et o thesexua ldimorphis m (femalesar elarge rtha nmales) .Figur e 6.5 showsa diagramo fth ediscriminan tvalue so fou rbird sfro ma functio nt o distinguishbetwee nmale san dfemale s (kindlyprovide d byMeint e Engelmoer).Bird swit hdiscriminan t scoressmalle rtha n0 shoul db e males,an dwit hscore slarge r than0 females .Figur e6. 6 showsth ebod y mass increases forth e twosex-groups .Female ssho wa linea rbod ymas s increaseo f0.5 6g/da yan dmale so f0.5 2g/day . Ifw ed oth ecalculation s witha somewha t safersexin gcriteriu m(e.g .discriminan t scoressmalle r

~~~~270 BODV MASS . G, 1?o~~~~

~~~~iSo~~~~

~~~~150~~~~

~~~~"f«0-~~~~

~~~~-JOO~~~~

FEBPUARV MARCH APWL Figure 5 6.6. Body mass increases of adult female and male Siberian Knots caught on the Banc d'Arguin in 1985/86,excludin g the light birds and those from the last catching period (cf.Fig . 9.6.3). The birds were sexed according to the discriminant function presented in figure 9.6.5. The dots give averages + 95%confidenc e intervals. orlarge rtha n0.8) ,th eresult sar eth esame ,althoug h theexplaine d variancesar esomewha tlower . Arrival timesi nWes tEurop e (Piersma,Bredi n& Prokosc hi nprep. ) indicatetha tth eKnot sshoul db eleavin g theBan cd'Argui n duringth e firstfe wday so fMay .A nextrapolatio no f theaverag ebod ymas sincreas e (Fig.6.4) ,suggest stha tth eaverag edepartur emas swoul db eabou t 160g .Thi si s2 0g les stha nth epredicte ddepartur emas so nth eBan c d'Arguin,a sestimate d byDic ke tal . (1987:Fig .9 )fro marriva lmasse s inSchleswig-Holstei n (theinferre dnex t stopoversite )an d thefligh t rangeformul ao fDavidso n (1984a).Note ,however ,tha tth e 'disappearance'o fbird sweighin g 170-190g betwee n 15-19an d 20-25Apri l (Fig.6.3 )indicate s thatsom ebird sma yleav ewit hpredicte dbod y masses.Th eaverag emas sincreas eo f0.5 6g/da yo nth eBan cd'Argui ni s farles stha nth eaverag emas s increaseo f3/da ymeasure d atLangebaa n Lagoon inSout hAfric aan d 4g/da y inth eWadde nSe a (Dicke tal . 1987).

~~~~271 PEßCE>XrAe£ soi~~~~

~~~~âo 100 no laotso-uo iso 160 12 3 CODY MASS ,G SUMMER PLUMAGE SCORE~~~~

Figure 6.7. Summer plumage and body moult scores in relation to body mass of juvenile Knots caught on the Banc d'Arguin in the springs of 1985/86 (A,B)an d the interrelation between the extent of summer plumage and body moult score (C).A plumage score of 1stand s for full winter plumage, 2fo r trace of summer plumage and 3fo r a quarter summer plumage. 6.4 Bodymoul tan dth eacquiremen to fsumme rplumag e 6.4.1 Juveniles. Thegrea tmajorit yo fcapture d juvenileKnot sshowe dn o bodymoul tan dn ochang efro mwinte r tosumme rplumage .Ther ewa sn o obviousrelatio nwit hbod ymas s (Figure6. 7 A,B). Juvenilebird swit h moresumme rplumag eincidentall y showeda highe rintensit yo fbod ymoul t (Fig.6. 7 C). Thegenera llac ko fformatio no fsumme rplumag esupport s theinterpretatio nbase do n(th elac kof )bod ymas schanges ,tha tth e greatmajorit yo f juvenileKnot sremain sa tleas t onesumme ro nthei r winteringgrounds .

6.4.2 Adults. Datao nth eexten to f summerplumag eo fadul tKnot s(Fig . 6.8),sho wtha tth ebird sproduc ea summe rplumag e inth eperio dearl y March-lateApril .Bod ymoul t ismos t intensei nlat eMarch-earl yApril .A comparisonbetwee n thedat acollecte d from 16Marc ht o1 9Apri li nth e twoyears ,give s somesuggestio ntha tth eKnot sma yhav ebee nslightl y moreadvance d in1986 ,o rtha ti n 1985ther ewer emor ebird swhic hlagge d behinda sfa ra sth edevelopmen to fsumme rplumag ewa sconcerned . Although thisi sno tclea rfro ma nexaminatio no f theaverage s (Fig.6.9) ,th esuggestio ni ssupporte d bymeasurement s ofth eexten to f

~~~~272 PEQCENTA.GE •too n=s t=EBOaAßy So : 19«« IBft£ 60 - 40 ,_ -~~~~

~~~~1 1 1 1 1 1 1~~~~

~~~~-1 I u 2 3 4 5 6 ? 1 2 J 4 5 6? SUMMER. qiaM-AGF SCORE~~~~

Figure 6.8. Development of the summer plumage of adult Knots on the Banc d'Arguin in the period February-April in 1985an d 1986,i n relation tobod y moult.Heav y shading refers to birds inmediu m or heavy body moult, light shading to birds in light body moult and no shading to birds without body moult.A summer plumage score of 4 stands for half summer plumage, 5 for 3/A summer plumage, 6fo r trace of winter plumage and 7 for full summer plumage.

273 summerplumag ea tWes tEuropea nstopove rsite s(Piersma ,Bredi n& Prokosch,I nprep.) : theysho wtha ti nth esam etim eo fth eyea rKnot s had amor efull ydevelope dsumme rplumag ei n 1986. Figure6.1 0show stw othings :bird swit ha mor eadvance dsumme r

~~~~AVEßACE SUMMER PlLUMAfiE SCORE~~~~

~~~~^^ +~~~~

~~~~O 1« • 1986 1 -~~~~

~~~~FEBRUARY MARCH APRIL~~~~

~~~~Figure 6.9.Change s inth eaverag e summer plumage scoreo fadul t Knots on theBan c d'Arguin inth ecours e ofsprin g (1985/86).Average s +95 % confidence intervals aregiven .~~~~

~~~~1385 1386 % ns -is 4 2 O p 8o FÜLL SUMME« w PLUMAGE 6, ? 6o wÊÊÊ, 1 40 wËÊÊÊ. 2o o~~~~

~~~~HALF TO THQEE- QOARTER SUMME RLÜMAGE M,S~~~~

~~~~16/3- 9A» -«O- W/u 20-26A4 16/3- 9/y 10-19/Ü~~~~

Figure 6.10.Interrelation s between theexten t ofsumme r plumagean d body moult intensity ofadul t Knots during thespring s of 1985/86o nth e Banc d'Arguin. Heavy shading refers tobird s with medium orheav y body moult, light shading tcbird s with light body moult andn oshadin gt o birds without anytrace s ofgrowin g belly andbreas t feathers.

!74 plumage show smaller body moult intensities,and : later in spring birds with amore ,bu t also with a less advanced summer plumage, show little or no body moult. This strongly suggest that before departing to the north birds stop body moult. This is even the case when the summer plumage is not yet fully completed: the 'decision rule'whethe r to finish summer plumage, or to stop body moult and leave summer plumage incomplete as to be able tomigrate ,appear s to change in the course of the spring season.

~~~~PLUMA& E BODV MOOl-T MOMBER OF ACfclCT VCKOT S~~~~

~~~~100 130 140 H60 4S0200 lOOtiOlOO 16o48 0 Ä» BOCV MASS.GRAH~~~~

~~~~E: d Kl WINTER, 4 MEO.- +4felkVy £.3 A.CE TD OME QU*WrEI^2,S UûUT, -t HALF TO THREE QCJXRTER,<« , HO. O re-m-, 6,?~~~~

~~~~Figure 6.11. The development of summer plumage and the intensity of body moult in relation to body mass and the time of the year in adult Knots on the Banc d'Arguin (1985/86).~~~~

275 7 Sanderling (Calidrlsalba ) CorJ . Smit& To mM .va nSpanj e 7.1 Introduction Ascompare d toothe rwade rspecie sSanderling sar erelativel y uncommono n theBan cd'Arguin .Altenbur ge tal .(1982 )counte dalmos t 34,000,whic h amounts toonl y 1.5%o fth etota lnumbe ro fwader swinterin g inth earea . Numbersi nth eBai ed'Aouati fvarie d from47 9t o938 ,thos ei nEbel k Aiznai (NorthwestBay )range d from3 0t o495 .Thes edat ahowever ,d ono t showa consisten t pattern.Number swen tu pfro m3 0t o49 5fro m2 4Marc h to2 2April ,an ddown ,u pan ddow nagai ndurin g thefollowin gcounts . Thesefluctuation sma yb ea resul to fmigration ,thoug h thepossibilit y ofchangin g populationsusin gEbel kAizna ia sa hig h tideroos tshoul d notb eexcluded . During lowtid eSanderling sar emos tnumerou so nbarre nsandflat s (mean 16birds/ha) . Inlo wdensitie s (1-2birds/ha )the yar eals ofoun d onsand yAre aan dsand yseagras sflat s (Altenburge tal .1982 )a swel la s alongth eedge so fth elarge rchannels .Durin ghig htid ethe yar eals o seenfeedin go ndrie d fishan dhuma nfoo dwast ei nth evillag eo fIouik . Occasionally theywer eals osee nfeedin gi nth ecamp .

7.2Catche s Addingu pth eresult so fbot hstud yyear sa tota lnumbe ro f5 4 Sanderlingswa scaugh ta tth eBan cd'Arguin .On eothe rbir dwa sfoun d alivei nNouadhibou ,caugh tb ychildre ni na snare .I twa sringe dan d released.Mos tSanderling s (28)wer ecapture d duringhig htid ei nth e villageo f Iouik,th egrea tmajorit yo f thesei ncla pnet safte r attracting thebird swit hdrie d fisho rfis hwaste .Anothe r 16bird swer e mist-netted onth eAre aflat so nth eopposit esid eo fth ecam p (site5 , Fig.7.1) .Usin g themethod soutline d byPrate re tal . (1977)2 2bird s wereage da ssecon d calendaryea rbirds ,3 1a sadults .Tw oothe rbird s couldno tb eage d successfully.Ther e isa strikin g difference inag e

276 compositionbetwee ncatches ,th enumbe ro fsecon dcalenda r yearbird s dominating inFebruar y (10secon d calendaryea rbird san d 2adult si n February 1986),th enumbe r ofadult sdominatin g inApri l (5secon d calendaryea rbird san d 26adult si nApri l 1985).Durin g theOxfor dan d CambridgeMauritania n expedition inSeptember-Novembe r 1973(Dic k 1985) 110Sanderling swer ecaught ,29 %o fthes ebein g juvenilebirds .Fo rth e momentsampl esize sstil lar eto osmal l tospeculat e onth ebackgroun do f thesedifferences .

~~~~Table 7.1. Bodymeasurement s (Inmm )o fSanderling scapture da tth eBan c d'Arguini nFebruary-Apri l 1985an d1986 .~~~~

~~~~2ndc.y . Adult Allbird s average ± S.D. average+ S.D . average+ S.D . range,numbe r range,numbe r range,numbe r~~~~

~~~~Winglengt h 123.3+ 2. 9 126.8+ 3. 7 125.4+ 3. 8 117-131;n=2 1 118-133;n=3 1 117-133;n=5 4~~~~

~~~~Billlengt h 24.8+ 1.3 24.6+ 1. 9 24.7+ 1.6 21.7-27.6;n-2 2 20.9-27.9;n-3 1 20.9-27.9;n=5 5~~~~

~~~~Totalhea dlengt h 50.0+ 2. 0 50.0+ 1.8 50.0+ 1. 9 46.8-57.3;n-2 2 45.5-53.1;n-3 1 45.5-57.3;n-5 5~~~~

~~~~Tarsusplu sto e 44.1+ 1.4 45.0+ 1.3 44.6+ 1.4 41-47;n-2 1 43-47;n-3 1 41-47;n-5 4~~~~

~~~~All 1985/86capture d birdswer enewl y ringed.N oretrap s (ownbirds ) orcontrol s (foreignbirds )wer eobtained .Eigh tbird sou to f the198 6 catchwer euse d forcag eexperiments .~~~~

7.3Biometric s Bodymeasurement so fSanderling scapture d in 1985an d 1986ar egive ni n Table 7.1.Adul twin g lengthsar ever ysimila rt ovalue sfoun d byDic ki n 1973(mea n 126.6+ S.E .0.3 1 forne wprimaries) .Win glength so fjuvenil e birdscaugh t byth e 1973expeditio nwer esomewha t longer (mean 124.8+ S.E.0.35) ,bu tthi sdifferenc e isno t significant (p>0.05,t-test) .Th e sameha sbee nfoun d inothe rspecies ,e.g .fo rLittl e Stint,an d couldb e a resulto ffeathe rabrasio ni nautum nan dwinter .Ther ei sn odifferenc e inbil llength sbetwee nsecon d calendaryea rbird san dadul tbirds .Thi s

277 applies both forth e 1973dat aa swel la sfo rthos efro m 1985/86.Mea n billlength so fbot hag eclasses ,however ,wer eabou t0. 5m mshorte ri n 1985/86a scompare d toDick' svalues .Agai n thisdifferenc e isno t significant. Table 7.2 shows thatbiométri eparameter san dweigh tar ehighl y correlated.A ver yhig hcorrelatio nwa s foundfo rbil llengt han dtota l headlength .

Table 7.2. Correlation coefficients of weight and biometrics of Sanderlings (all age classes), n=55. Coefficients significant at the 0.05 level are marked with *, those at the 0.01 level with **an d those at the 0.001 level with ***.

~~~~Weight Wing Bill Total head length length length~~~~

Wing length 0.5826*** Bill length 0.5047*** 0.4417** Total head length 0.4075** 0.4368** 0.7924*** Tarsus plus toe 0.3811** 0.4713*** 0.3148* 0.3556**

7.4Weight s Weightsuse d inthi schapte rhav ebee ncorrecte d forweigh t lossbetwee n catchingan dweighing .Dat ao fonl y6 bird swer eavailabl efo r correction.Assumin gweigh tlos si slinea r thefollowin gequatio nwa s found: corrected weight =uncorrecte dweigh t+ (0.52T -0.41)

whereT,. _= tim ei nhour sbetwee nfirs tan dsecon dweight .Applicatio n alt ofthi sequatio nlead s toa napproximat eweigh tlos so f0. 5g/h .Despit e thesmal lnumbe ro fbird sthi sfigur ei sbase d upon,i ti si nrathe rgoo d agreementwit hearlie r findings.Schic k (1983)foun d thatSanderling s lost 1.2g o fthei r initialweigh t inthei rfirs thou ro fcaptivity .I n thefollowin ghour sweigh t lossdroppe d to0. 4g/h ,agai nlate rt o0. 3 g/h.A tth eBan cd'Argui nSanderling swer ekep t4.0 4hour s+ S.D . 2.47 (n=50)o naverag ebetwee ncatchin gan dweighing . Corrected weights ofsecon dcalenda ran dadul t Sanderlingsar egive n intabl e 7.3.Dic k (1975)foun d 43.9+ S.E .0.5 7 gfo rjuvenile san d45. 4

~~~~278 WEICHT, G~~~~

~~~~• • • 52 -~~~~

~~~~• o o • 46 • • O • • o o o o o o o 44 o • ooo o o AO — o o~~~~

~~~~1 1 -J-- 1CV2 3CV2 WI2 10/3 20/3 Jl/3 10/4 HOM 30/u~~~~

Figure 7.1. Weights (grams)o f Sanderlings, captured at the Banc d'Arguin in February-April 1985/86.OPe n circles refer to second calendar year birds, dots to adults.Weight s have been corrected forweigh t loss between catching and weighing.

+ S.E.0.3 9 foradult si nSeptember-Novembe r 1973.Thoug h thesampl esiz e ofou rFebruar ycatche si ssmall ,weight sma yb econsidere d comparablet o thosefoun di n 1973.Onc eagai n (followingDic k1975 )w ema yconclud e thatSanderlin gweight si nMauritani ai nwinte rar eth elowes tfoun d anywhere. Threebirds ,die ddurin gcaptur eo rdurin g their stayi nth ecages , wereanalyse d onfa tconten tafterwards .Result so fthi sanalysi san d biométriedat aar egive ni ntabl e 7.4.Lea nweigh t figuresar e considerably belowth e5 5g w earriv ea twhe napplyin g thelea nweigh t equationgive nb yMcNei l& Cadieu x (1972). Weights,especiall y ofadul tbirds ,increas ei nth ecours eo ftime . Figure 7.1demonstrate s thatadul tweigh t increase probably startsaroun d midMarch .Becaus ever y littleinformatio n isavailabl e forFebruar yan d March iti simpossibl e tob emor eexplici tabou tth estar to fth e fattening up.Mor eo rles sth esam eapplie s forth efattenin g upo f

~~~~279 Table 7.3. Corrected mean weights (grams)o f second calendar yearan d adult Sanderllngs captured at the Banc d'Arguin in February-April 1985/1986.~~~~

~~~~Month 2nd c.y. Adult average + S.D. average + S.D. range, number range number~~~~

~~~~February 44.1 + 3.1 46.5+ 3.5 40-49; n-10 44-49;n- 2~~~~

~~~~March 44.6+ 2.6 48.5+ 0.7 42-49; n=5 48-49;n» 2~~~~

April 44.7+2.7 54.5+6.0 40-47;n» 6 42-66; n=24 second calendaryea rbirds .Th efe wyoun gbird scapture d inApri ld ono t showa ver yobviou sweigh tincrease ,suggestin g thatthe ysumme ra tth e Bancd'Argui n orleav e latera scompare d toth eadults .A linea r regressiono fadul tweigh tincreas eove rApri lyield s0.3 6g/day ,whic h ishig ha scompare d toRedshan k (sameincreas ebu ta large r bird),bu t somewhat lowera scompare d toDunlin .Migran t individualDunlins , retrappedwhil edepositin g fati nGrea tBritain ,increase d inweigh ta t meanrate so f0.7-1. 0g/day . InSwede nDunlin seve ngaine d 1-3g o f weightpe rda y(Pienkowsk i& Evan s 1984).Maximu mweight s ofSanderling s at theBan cd'Argui n byth een do fApri lamounte d to59-6 6g .Thi si slo w ascompare d tosprin gweight s fromBritai n (meanweight sfro mJun e74. 0 g,n=234 ;Johnso n 1985)an dSout hAfric a (departingweight sestimate da t 95g ;Summer se tal . 1987).Assumin ga fligh tspee do f6 5km/ h (McNeil& Cadieux 1972)an da lea nweigh to f4 6g ,Sanderling so f59-6 6g hav ea

~~~~Table 7.4. Biometrical data (mm)an d weights of three Sanderlinsg analysed on fat content (data by Nelly van Brederode).~~~~

~~~~Date Age Fresh Wing Bill Total Tato Lean weight length length head weight~~~~

~~~~13Apri l 1985 ad. 56 125 25.5 51.5 44 49.7~~~~

~~~~14Feb . 1986 2nd c.•y - 44 120 25.3 49.6 44 39.6 15Feb . 1986 2nd c •y > 47 124 25.3 50.7 46 40.3~~~~

280 potential flight range if 1,500-2,300k m (Davidson 1984). This fat load will bring them to theMorocca n coast,an d itmean s that their flight range is only half the size,o r less,a s compared to Sanderlings from Britain and South Africa. This may implicate that Sanderlings captured at the Banc d'Arguin either were still in the process of fattening up,o r that flight ranges of birds leaving the Banc d'Arguin simply are rather small. According toDic k (1975) Sanderlings are numerous along the Mauritanian mainland coast between Cap Timiris and Nouakchott. The same applies for the Senegalese coast where De Smet & Van Gompel (1979)

~~~~PUiMASE~~~~

~~~~Sé - 5 - 0ttl I« - o« •••~~~~

~~~~3 - m IM.«« 2 - 8o • § o W1 gpo CO «o •~~~~

~~~~I ! I Il I I I I~~~~

~~~~Figure 7.2. Plumage of Sanderlings at the Banc d'Arguini n February-April 1985/86.Ope n circles refer to second calendaryea rbirds , dots toadults .~~~~

~~~~BODY MOULT WEAVy 3-~~~~

~~~~WOWE~~~~

tO/2IOIZ2SJ2 10/32DI331/3 ¥>H2D/(A SOM Figure *7.3 . Body moult of Sanderlings in the course of spring at the Banc d'Arguin.Ope n circles refer to second calendar year birds,dot st o adults. counted over 6,000, being themost numerous wader species. The same may apply for sand beaches further north along the African coast.A possible explanation for the rather lowweight s at the Banc d'Arguin therefore may

281 be that the birds do not migrate over large distances. Since we have no records of visible migration and counts only yielded varying numbers, the first explanation (birds still were in the process of fattening up by the time the expedition left the Banc d'Arguin)stil l remains open. In western Europe high numbers of Sanderlings are recorded in the third May decade (Smit 1987). Thisma y imply that departure from the Banc d'Arguin occurs relatively late.

7.5 Plumage From the end ofMarc h onwards,Sanderling s start coming into summer plumage bymoultin g body feathers (Figures 7.2 and 7.3).Th e start of body moult lags behind about 1-2 weeks after Sanderlings start building up fat reserves for migration. It is striking that by the end of April no birds at all have attained full summer plumage, though they are in heavy bodymoult . This means that Sanderlings either continue their body moult while onmigratio n or do not leave yet until plumage moult has been partly or fully completed. Our findings corresponds with literature

~~~~1 d"klE CAUADA , ru5 A Ç GREENLAND, H= 5^ 1 7 9 INDONESIA, n=? 29 HE CANADA, n^3 5 OEOnOP *JS5>R, riij 3cfußEEMLAND , n= A3 6 cf INDONESIA , Hs9~~~~

~~~~Biu. LEMSTM , MM~~~~

~~~~28 - • 0 • • 0 1 s { • • 1 • 26 • 0 —<2)- 8 • 1 Wv —O—Yt hr • ft —•— 0 ~1 m 1 8 • • 2A 0 —0— —*— 0 0 =•8 • Lh~ 1 O • 0 • • 22 • 0 • 20~~~~

1 1 1 i 1 1 1 1 1 11s 120 122 im 126 128 130 132 434 WING. LEMCnH, MM Figure ?7.4 . Wing length -bil l length relation of Sanderlings captured at the Banc d'Arguin and mean lengths and standard deviations of Sanderlings populations elsewhere (based on museum skins,correcte d from shrinkage). Open circles refer to second calendar birds,dot s toadults . information.Accordin g toCram p& Simmon s (1983)adul t Sanderlingsmoul t parto fthei rbod yfeather s inth esecon d parto fApri lan di nMay ,som e featherseve nbein greplace d aslat ea smid-July .Som esecon dcalenda r yearbird sals osho wbod ymoul tan dals oattai nsom esumme rplumage .The y do,however ,la gbehin d theadults .Agai nthi si si nagreemen twit h literature.Accordin g toCram p& Simmon s (1983)sprin gbod ymoul ti n juveniles ishighl yvariabl ean dmainl y takesplac e inMay-June .On ebir d ofunknow nage ,weighin g 47grams ,capture d on2 8Apri l 1985wa si n activewin gmoul t init soute r twoprimarie s (5555555543).

7.6Geographica lorigi nan dmigratio n Ananalysi so fth ewin glength-bil llengt hrelatio no fbird scaugh ti n Mauritaniai n1985/86 ,togethe rwit hbiométri edat afro mbreedin garea s inth enearcti can dsom estop-ove ran dwinterin gsite si nth ePalearcti c (Fig. 7.4)yield sn oinformatio no nth epossibl eorigi no fth e Mauritanianbirds .Ther ei sa considerabl eoverla pi nsize sbetwee n Nearctican dPalearcti cbreedin gpopulation san dth epatter ni seve nmor e obscuredb y thesiz edifferenc ebetwee nsexes .Bird scaugh ti nMauritani a muchvariation ,bot hi nwin glengt han di nbil llength .I ti sstrikin g thatsom erelativl y small-winged andsmall-bille d birdshav ebee ncaught , both secondyea rbird san dadults .Thes emeasurement s point towardsWes t Siberianbirds .Uspensk i (1969)give swin g lengthso f 115-124m m(mea n 118.6)fo r3 0female s fromSiberi a (exactlocatio nunknown )an d 115-126.5 mm (mean 121.9)fo r3 0females .Bil llength so fthi spopulatio nar e 20.8-26.0fo rmale san d 20.2-27.6fo rfemales .Th elowe rpar to fth e rangeo fmeasurement so fbird sencountere d inMauritani a isbelo wth eon e found inNearcti cbird s (Cramp& Simmon s 1983,Engelmoe r 1984).Thes e measurementshoweve rd ocoincid ewit hsmall-winge d andsmall-bille dbird s captured inSout hAfric a (Summerse tal . 1987).o fth elatte rpopulatio n havebee nrecorde d inSiberia nbreedin gsite san d stop-overarea salon g theBlac kSea ,Caspia nSe aan dMediterranean ,th elatte rarea sals o pointing tomigratio ntoward sSiberia nbreedin gareas .Additionall y there ison eMay-resightin go fa 1985dye dSanderlin gfro mth e Schleswig-Holsteinwes tcoast ,als opointin g towardsmigratio nt o Siberia.O nth eothe rhan d therear ethre esprin g recoverieso f Mauritanianringe d Sanderlings fromth eEnglis hwes tcoast ,bird s probablybelongin g toth eGreenlan d breeding population (Dick 1975). Thesedat aclearl y suggest thatSanderling so fbot hNearcti can d Palearctic originar ewinterin ga t theBan cd'Arguin .

283 MarkR .Fletche r 8 LittleStin t (Calldrisminuta ) 8.1Introductio n Little Stintsar ever ycommo nan d fairlynumerou sove rmoß tpart so fth e areao fth eBan cd'Argui nan d Iouik.Thes ebird swer eobserve d feeding over themudd yare aarea so fth emudflat sa tan ytim ethi swa sexpose d and,t oa lesse rextent ,feedin goccurre da tth ewater sedge .

8.2Ringin gstudie s A totalo f27 4individual swer ecaught ,al li nmis tnets .Th emajorit y werecaugh teithe ra tth elin eo fnet snea rth eairstri p ando nth e mudflats opposite thecam psite .Som ebird swer eeve ncaugh tdurin g daylight.Th ebird swer enette d inth eNorthwes tBay .Fou rbird swer e retrapped,on eo fwhic hwa sretrappe d twice.A singl ebir dwa scontrolle d whichha dbee nringe d inNorwa y (seeTabl e7.8) .Ful lbiometric swer e takeno nal lbird scaught .Th emajorit y ofbird scaugh twer eage da s adult (216,78.8% )an d fiftybird swer eage da sjuveniles .Ther ewer e eightbird s thatwer eno taged .Th eagein gtechniqu euse dwa stha t outlined byPrate re tal . (1977).Th ejuvenile swer ecaugh tthroughou t thestud yperio d (8February-2 2April) ,wit ha large rproportion ,abou t 25%o fth epopulation ,a tth efirs tpar to fth estud y (8February- 5 April).Th eproportio ndroppe d toabou t 7%i nth eremainin g time.Thi s contrastedwit hresult sobtaine d byKnigh t& Dic k (1975)wh ofoun do nth e Bancd'Argui n 86%juvenile sa t thebeginnin go fOctober ,82 %a tth een d ofOctobe ran d 60%i nmid-November .

8.3 Biometrics Themea nwin g lengtho fal lbird scaugh twhic hha dwing s thatcoul db e measured,i.e .oute rprimarie swer eno t inmoult ,wa s97. 9m m (S.E.+ 0.20).Th erang ewa s91-10 6m m (n=231).Juvenil ewin glength sha da mea n of97. 4m m (S.E.+ 0.62),rang e92-10 3 (n=34)an dadult s98. 0m m (S.E.+ 0.22),rang e 91-106 (n=189).Femal eLittl e Stintshav e longerwin g lengthstha nmale san d therang ethroughou tth eperio do fth estud y

28A suggested thatbot hfemal ean dmal ebird swer epresen ta tal ltimes .Th e winglength showeve rwer eo naverag elonge rtha nthos efoun db yEtheridg e (1971)i nth eTrucia lState si nlat eDecembe r (mean95. 5mm ,rang e93-9 9 (n=7)).Th eadul twin glength swer ever ysimila rt othos efoun d byDic k (1975)mea n98. 4m mbu t thejuvenil ewin glength sfoun db yDic kwer eo n averagelonge r 99.7m m (n=46).Win glength sa tth elowe ren do fth erang e inth estud ywer esmalle rtha nthos epublishe d in 'TheBird so fth e WesternPalearctic '(Cram p& Simmon s 1983). Themea nbil llengt ho fal lbird s (n~244)wa s 18.7m m (S.E.+ 0.06) witha rang eo f 15.1-21.1mm .Fo r juvenilebirds ,mea nbil llengt hwa s similart othos eo fadults .Th edistributio no fwin glengt hi sshow ni n figure9.8.1 . Cramp& Simmon s (1982)giv ea rang efo rbil llengt ho f 16.7-19.9m mfo r museumspecimens .Seve nbird swer efoun d tohav ebil llength sshorte r thanthi srange ,wit hon ebir dver ymuc h shorter 15.1mm .I nadditio n

~~~~NUMBER~~~~

~~~~92 9« 96 10D Ktt AOU ^oe^ \*/INÄ LENSTW~~~~

~~~~Figure 8.1. Distribution of wing lengths of Little Stints caught on the Banc d'Arguin in 1985/86.~~~~

285 ninebird sha dbill slonge r thanth equote d rangewit hon ea t21. 1mm .I n general thebil llength swer esimila r tothos efoun db yDic k (1975)i n Mauritaniaan dEtheridg e (1971)i nth eTrucia lStates . Otherbiometric s taken(othe r thanweight ,se ebelow )include d total headmeasurements ,givin ga noveral lmea no f38. 7m m (S.E.+ 0.07 )an da rangeo f32.5-41. 9m m (n=244).Th esmalle rbille d birdsals ogav esmalle r headmeasurement sgivin gconfidenc e thatrecordin g errorswer eprobabl y notmad ewhe nmeasurin g thesesmalle rbills .Ther ewa sn odifferenc ei n thetota lhea dmeasurement s ofadult san d juvenilebirds . Thedifferenc ebetwee nsexe si ssignifican t forbil li nLittl eStints , male 18.1m m (range 16.7-19.2mm) , female 18.5m m (range 17.5-19.9mm )a s outlined byCram p& Simmon s (1983). Alsorecorde dwa sth ecombine d tarsus+ to emeasurement .Th eaverag e ofthi smeasuremen twa s39. 7m m (S.E.+ 0.1),rang e36.0-47. 0m m (n=243). Therewa sn odifferenc e inth etarsu s+ to emeasurement sbetwee n juvenilesan dadults .

8.4Weight s Themea nweigh t foral lLittl eStint swa s23. 8g (S.E .+ 0.2 )wit ha rangeo f 17.0-35.0g (n=241).Juvenil emea nweigh twa s21. 4g (S.E .+ 0.37),rang e 18.0-30.5g (n=3ö)an dadult s24. 3g (S.E .+ 0.23),rang e 17.0-35.0g (n=195).Thes eweight swer etake nthroughou t thestud yfro m8 February to2 2April .Ove r thisperio d themea nweigh tincrease d particularly foradul tbird s(Tabl e8.1).

~~~~Table 8.1. Meanweight s(I ngram )o fLittl eStint si nthre eperiod s between8 Februar yan d 22Apri l(198 5an d 1986).~~~~

~~~~8-13 Feb 1-9Ma r 13-16Ma r~~~~

~~~~Allbird s 20.8g (n=ll) 21.2g (n=20) 21.5g (n«=8 ) Juveniles 23.0g (n=1 ) 20.3g (n-=10) 19.0g (n=2 ) Adults 20.1g (n=9 ) 22.1g (n-10) 22.6g (n-5 )~~~~

~~~~22Mar- 5Ap r 10-16Ap r 17-22Ap r~~~~

~~~~Allbird s 22.4g (n=95) 25.0g (n«122) 25.6g (n=18) Juveniles 20.9g (n=23) 22.4g (n-10 ) 22.3g (n=1 ) Adults 23.1g (n=66) 25.3g (n-112) 25.8g (n=17)~~~~

286 However,ofte nweight swer erecorde d sometim eafte rth ebir dwa s capturedan dweigh t lossesar eknow n tooccu rwit htime .I nsevera lcase s a secondweigh twa s takenafte ra know nperio d oftim ei na nattemp tt o assessthi sweigh t losswit htime . Ifi ti sassume d thatthi sweigh t lossi slinear ,th efollowin g equationca nb eapplied : WDif= - 0.24 9+ 0.34 1 TDif (r2-0.54) whereWDi f= differenc ei ngram sbetwee nfirs tan d secondweight ,an d TDif -tim ei nhour sbetwee nth etw oweights . Thisgive sa weigh tlos so f0. 3g/h .I ti sprobabl etha t theweigh t lossi nth efirs thou ri sgreate r thanthis ,wit ha lowe rdecreas ei n weighta stim eprogresses .Becaus e thetim eo fcaptur ewa sapproximatel y knownan dth etim eo fweighin gwa srecorded ,i ti spossibl e tocorrec t theweight so fth ebird susin g theabov eequation .Thi swa sthe nuse dt o givea mea ncorrecte dweigh t foral lbird so f25. 3g an da rang eo f 17.9-36.5g .Juvenil emea nweigh twa s25. 5g ,rang e 17.9-36.5g . Correctedmea nweight sove rth eth eperio d ofth estud yar eshow ni n table8.2 .

~~~~Table 8.2. Corrected mean weights of Little Stints in time periods between 8 February and 22Apri l (1985 and 1986).~~~~

~~~~8-13 Feb 1-9 Mar 13-16Ma r~~~~

~~~~All birds 21.4g 21.6g 21.8g Juveniles 23.7g 20.7g 19.1g Adults 20.7g 22.5g 22.9g~~~~

~~~~22Mar- 5 Apr 10-16 Apr 17-22Ap r~~~~

~~~~All birds 23.4g 26.9g 27.1g Juveniles 22.0g 23.5g 24.1g Adults 23.9g 26.4g 27.3g~~~~

Theweigh t increasewit htim ei sstil lpresen twit h theadul tbird san d thisma ysho wa pre-migrator y increasea t theBan cd'Argui nprio rt o departurenorthwards .Becaus e thisincreas e isno ts oapparen ti n

287 juvenilebird si ti spossibl e thatsom ema yb epassin gthroug han d feeding furthernort h prior tomigratio no rhav eincrease d theirweight s furthersout han dar eover-flyin g theBai ed'Aouatlf .Howeve rcar emus t be takeni ninterpretin g theweight s ofth ejuvenile sa sth esampl ewa s small. Dowsett& Fr y (1971)showe d springweight so fLittl e Stintsa tLak e Chad in196 7t ohav ea mea no f22. 9g wit ha rang eo f 19.9-27.5g (n=7 ) andi nsprin g 1968 23.3g ,rang e 18.4-30.2g (n=44),value slowe rtha n thosefoun d inApri l1985 . Themea nweight si nthi sstud ywer eals over ymuc hhighe rtha nthos e found byDic k (1975)i nwinte ri nMauritania ;juvenile smea nweigh t 18.8 g (n=52),adult smea nweigh t 22.0g (n=19);an db yEtheridg e (1971)i n lateDecembe r inTh eTrucia lStates ,mea nweigh t 21.0g (n=7).

8.5 Moult Theprimar ymoul to fLittl eStint scaugh tdurin g thestud yi nth eBan c d'Arguinappear s tob ever ycomplex .Moultin g birds,bot hadult san d juvenileswer ecaugh t throughout theperio do fth estudy .I nman ycase s themoul tappeare d tob ecomplet ewit hth eapparen t renewalo fal l primary feathers.Thi sapplie d toth emajorit yo fadult s (94%)an dsom e juveniles (18%).Severa lbird swer ei nth eproces so fmoultin gal lthei r primary featherswit hmoul t scoresbetwee n2 2an d 49.I nthi scategor y wereman yo fth e juveniles (36%)an da smal lnumbe ro fadult s (3.7%)an d threeunage d birds.Th e juvenilesha da lowe rmea nmoul t scoreo f3 5 comparedwit h theadult swhic hha da mea nmoul tscor eo f46 .Sample so f bothjuvenile san dadult smoultin g inthi swa ywer e found throughoutth e studys othe yar eno tbiase db yth etim eo fcatching . Inanothe rgrou po fbird sth emoultin g orremoultin go fsom eo fth e outerprimarie swa sfound .Ther ewer e2 3juvenile s (46%)i nthi s category.Pearso n (1984)suggeste dwhe nh efoun d thisi nhi sstud yo f LittleStint si nth eRif tValley ,Kenya ,tha tthes ebird sma yhav e startedmoultin g late,perhap sJanuary-February .Fiv eadult san dtw o unagedbird swer eals omoultin g theoute rprimarie swit hol dinne r primaries.Pearso n (1984)suggeste d forthes ebird s that theyma yhav e moulted early thepreviou syea ran dwer eremoultin g theseoute r primaries.Stanyar d (1974)suggeste d thatearl ymoultin g LittleStint s inBotswan awer efaile d breeders.Th enumbe ro fothe r feathersbein g

288 moultedvarie d considerably fromver y fewt onearl y all.Ther ewa son e bird (juvenile)whic hshowe darreste dmoul twit ha moul tconfiguratio no f 73 N0 .Arreste dmoul t inLittl eStint sha sbee nrecorde d byDowset t& Fr y (1971)a tLak eChad ,an dPienkowsk ie tal . (1976)o nth eAtlanti ccoas t ofMorocco .I nbot hthes ecase sarreste dmoul twa srecorde d inSeptember . Bodymoul twa srecorde d inth emajorit yo fbird san d therewer ebird s caught showingful lwinte rplumag erigh t throughvariou sstage st oful l summerplumage .

289 NellyE .va nBrederod e 9 CurlewSandpipe r vCalidrisferruginea ) 9.1 Sex-,age-ratio s andmeasurement s Wecapture d 90Curle wSandpipers ,5 4adults ,3 5secon dcalenda ryea r birds (2ndc.y. )an don ebir d ofunknow nage .Accordin g toth e discriminant functiondevelope d foradul tbird sb yEngelmoe r (1984),i n whichbot hbil lan dwin g lengthar e involved (y= 0.074789 4 *winglengt h +0.4863466*bil llengt h -28.52034),ou rsampl eo fadult scomprise d 23 femalesan d 30males .I non eadul tcatchin gcasualt y sexingb ydissectio n confirmes thepredictio n (Table9.1) .Bil llengt hi sth emos t discriminatory feature,s oi nmos tcase si ti spossibl et oseparat emale s andfemale sb yusin ga bil llengt ho f38. 3mm .Sinc ebil lan d totalhea d lengthar elinearl yrelate d (r=0.96;Fig .9.4 )i ti sno tsurprisin gtha t totalhea d lengthi sals oa sexuall ydimorphi c feature (Fig.9.1) .Win g andbil llengt har eno tlinearl y related (Fig.9.5) ,neithe rar ewin gan d totalhea d length (Fig.9.6) .Furthermor e therei sn oclea rbi-modalit y inwin glengt h (Fig.9.2) .Th eonl ystrongl y sexuallydimorphi cfeatur e orCurle wSandpiper si stherefor ebil llengt h (Fig.9.3) . Themea nbil llengt hfo radult s (Table 9.2)doe sno tdiffe r significantlyfro mthos emeasure d duringtw osprin gexpedition st o Morocco (Kerstene tal .1983 ,T-test ,df=55 ,t=0.69 ;Va nBrederod ee t

~~~~KUJMSEft -uT~~~~

~~~~_L 1 L n 58 6o 62 6^ 66 68 TOTAL 4-tEAD LEKK3IH MM~~~~

~~~~Figure 9.1. Frequency distributions of total head length of adult Curlew Sandpipers (n=52)caugh t at Iouik,Mauritani a in 1985an d 1986.~~~~

~~~~290 N^JMBei? ^6~~~~

~~~~12-~~~~

~~~~s - 4 -~~~~

~~~~1 1 r~ï 42*1 1M 132 136 140 WINS LENŒ.TW, V»M~~~~

~~~~Figure 9.2. Frequency distribution of wing length of adult Curlew Sandpipers (n=53)caugh t at Iouik,Mauritani a in 1985 and 1986.~~~~

~~~~NUMBER~~~~

~~~~36 4o 42 44 BILL UENSTM, MM~~~~

Figure 9.3. Frequency distribution of of bill length of adult Curlew Sandpipers (n=53)caugh t at Iouik,Mauritani a in 1985an d 1986. al.,i nprep. ,T-test ,df=70 ,t=0.67) ,bu tdoe ssignificantl ydiffe rfro m meanbil llength smeasure d duringa winte rexpeditio n toMauritani a (Dick etal . 1975,T-test ,df=402 ,t=2.35 )an d twoautum nexpedition st o Morocco (Pienkowskie tal . 1972,T-test ,df=63 ,t=5.10 ;Mose re tal . 1980,T-test ,df=87 ,t=2.00) .Th edifferenc ewit hth eautum nfigure si s probablycause d byth edifferentia ltimin go fautum nmigratio nb ymale s and females,th emale smigratin gearlie ran dleavin g toincubat ean dten d theyoun g (Portenko 1959). Insprin g therei ssimultaneou snorthwar d migration (Elliott etal . 1976)an d simultaneousarriva lo nth ebreedin g grounds (Portenko 1959).Th eautum n figuresfro mMorocc oals o illustrate thispoint :th emea nbil llengt hfo radul tbird scaugh t inJul yan d August issignificantl y lower thantha t foradul t birdscaugh ti n September (Pienkowskie t al. 1972;Mose r etal .1980 ;T-test ,df=44 ,

Ï91 t=l1.24). InMauritani a therei sn osignifican t differencea tth e5 % levelbetwee n thenumbe ro fadul tmale san d femalespresen t inFebruar y 2 comparedwit hMarc h (x=0 ,df=l )an d inFebruar yan dMarc hcompare dwit h April (x2=2.77,df=l) .

~~~~BILL LEHGTTW. MM 44 •~~~~

~~~~42 •: • • •~~~~

~~~~40 . • • • • •• •A 38 I~~~~

~~~~• •~~~~

~~~~36 • • • • • • • • 34 •~~~~

~~~~i i i i i i 56 55 €o 61 6U, 66 6S TCTA4_ MEAD l_eK>«TV*,~~~~

Figure 9.4. Therelationshi pbetwee nbil lan dtota lhea d lengthi n adultCurle wSandpiper s (n=52),y = -20.7 3+ 0.95 x(r-0.96) .Th e horizontallin edivide sth efemale s (top)an dmale s(bottom )accordin gt o thediscriminan t function(se etext) .

~~~~IBU X LENX5TH, MM~~~~

~~~~44 • • • • • «0 f • • * h • • 1 • 1 • 36 : . •• • t • • 32~~~~

i i i i » W 128 132 136 WO WING LEKW3.TM , MM Figure 9.5. Therelationshi pbetwee nbil lan dwin glengt hi nadul t CurlewSandpiper s (n*=52),y = 59.7 2- 0.1 6x (r=-0.20).Th ehorizonta l linedivide sth efemale s(top )an dmale s (bottom)accordin g toth e discriminant function (seetext) .

~~~~292 TOTAJ. -MEAO LENGTH , MM 66~~~~

~~~~64_ ::•«. •• ••~~~~

~~~~60 L !•'. «*.. • •~~~~

~~~~56f -~~~~

~~~~_l_ 12*4 129 132 136 440 iOa WIN& UEMG.TM, HM~~~~

Figure 9.6. The relationship between total head and wing length in adult Curlew Sandpipers (n>=51),y - 82.55 - 0.15x (r=-0.18). The horizontal line divides the females (top)an d males (bottom)accordin g to the discriminant function (see text).

Inou rdat aneithe rbil llengt h (r=-0.08)no rwin glengt h (r=-0.04) correlateswel lwit hweigh tdurin gth esprin gperio dwhe nther ei sn o increasei nweigh tye t (before 15March) ,s othes emeasure scanno tb e useda sa nindicatio nfo rstructura lsize . Inorde rt ose eho wmuc hweigh tbird smigh tloos ebetwee ntim eo f capturean d timeo fmeasurement ,w emeasure d rateso fweigh t lossi na smallsampl eo fbirds .On ebir dreweighe d afteron ehou rha d lost 1.7g , threebird sreweighe dafte r4- 5hour slos to naverag e0. 8+ 0. 4g/h , eightbird sreweighe dafte r 10-12hour slos to naverag e0. 6+ 0.0 6g/h . Thegreates t rateso fweigh t losstherefor eoccu ri nth efirs thour so f captivity.Th eaverag eweigh t losso fal l 12bird s is0.7+0. 4g/h .I n practice thetim ebetwee ncaptur ean d firstweigh ti so naverag e4. 4+ 1.7h (n=87).S oou rcorrectio nwit h0. 7g/ hi sconsidere d aminimum .

~~~~Table 9.1. The fresh and fat-free fresh weights and the sexing data (see text)o f three Curlew Sandpipers caught and dissected at louik, Mauritania, in spring 1985an d 1986.~~~~

~~~~Age Fresh weight fff-Weight Sexing by Sexing by (in gram) (in gram) dissection discriminant function~~~~

~~~~Adult 67.8 52.6 male male Adult 60.1 51.1 unknown male 2nd c.y. 56.8 48.1 male -~~~~

~~~~203 COBÄBCTBO WEIGHT;~~~~

TA • • • TO • • • • •• • €é t • • • •• 61 ;•• • • • • t • 56 • • • • • •• • • X 54 t * f •• -* * • *** • - • • • so • AM • 46

42 . 1 i i i i i i i 1 1 1 i I i i i a/2 XV2 WL2* 22atl S/& 1Qtt16/ 32Q32S/3*>34A 4S MM/ M -»/«SK*

~~~~~~Figure 9.7. The connected weights of Curlew Sandpipers (n*=87)caugh t at Iouik,Mauritani a in 1985an d 1986( • adult,* 2nd c.y.).~~~~~~

Theserate so fweigh t lossar elarge rtha ntha to f0. 4g/ h foundi n Morocco (Kerstene tal . 1983), possiblybecaus eth ehighe rai r temperatures inMauritani a resulti nhighe rrespirator ywate rloss . Theweight so fadul tbird svar ybetwee n 47.8g an d 63.3g i nFebruar y and thefirs thal f ofMarc h (Fig.9.7) .I nth esecon dhal fo fMarc han d inApri lth eweigh tgenerall y increases,u pt oa maximu mo f76. 8g .I n thisgrou p (n=40)ther ei sa linea rrelatio nbetwee nweigh tan d timefo r birdswhic hweig hmor e thanth eaverag efat-fre efres hweigh t (fff-weight)fo rCurle wSandpiper s (seefligh trange ;r=71 ,y = 55.7 6+ 0.48 x).Thi sma yindicat etha tbird sar epreparin g formigration , gaining0.4 8g/day ,an dindee d ourhig htid ecount ssho wtha t therei sa largeris ean da nequall ylarg edro pi nnumber so fbird si nApril .Th e increasei nweigh t inthi sgrou p isalmos t 1%o fth efff-weigh t perday . Thetw oadul t birdswhic hhav ebee nexclude d fromthi sgrou pbecaus ethe y weighles stha nth eaverag efff-weigh tma yhav e justarrive d fromth e south.Furthe r studiesma ysho wtha tther ei sindee ddifferen t timingo f migrationan d thereforedifferen t timingo fincreas ei nweight .

194 Theweight so fsecon dcalenda ryea rbird svar ybetwee n42. 8g an d57. 1 g inFebruar yan d thefirs thal fo fMarc h (Fig.9.7) .I nth esecon dhal f ofMarc han d inApri l theweigh t increasesbu tno ta smuc ha sfo rth e adults.Th emaximu mi s63. 2g .Thi smigh tindicat e theyeithe rmigrat e later inth eseaso no rtha tthe yd ono tmigrat ea tall .Fo r thebird s caughtbefor e 15Marc h therei sn osignifican tdifferenc ei nweigh t betweenadult san d juveniles (T-test,df-36 ,t-1.81) ,fo r thebird s caughtafte r 15Marc h therei sa significan tdifferenc e (T-test,df=48 ,

Table 9.2.Measurement so fCurle wSandpipe rcaugh ta tIoulk , Mauritania,i nsprin g 1985an d 1986.Ther ei sn obir do funknow nag ean d oneadul twhic hcoul dno tb esexe db ydiscriminan t function (seetext) .

~~~~~~2ndc.y . (35) Adultmale s(30 ) Adultfemale s(23 )~~~~~~

Winglengt h(mm ) 128.5+3.5 132.6+3.1 132.1+2.8(22) Billlengt h (mm) 37.0+2.2 36.5+1.0 40.6+1.3 Totalhea d1 .(mm ) 60.6+ 2. 1 60.4+ 1.0(29 ) 64.6+ 1. 4 Tarsus+ to e(mm ) 53.7+ 2. 0 53.5+ 1.4 54.7+ 1.8 Weight (g), uncorr. 49.7+ 4. 1 (34) 58.4+ 6. 8 55.8+ 7. 7 Weight (g),corr . 51.8+4.7(34) 61.7+6.8 58.3+7.6

~~~~~~Alladult s(54 ) Allbird s(90 )~~~~~~

Winglengt h(mm ) 132.4+ 2. 9 (53) 130.8+ 3. 7(89 ) Billlengt h 38.3+2.3(53) 37.8+2.4(89) Totalhea d1 .(mm ) 62.3+ 2. 4(52 ) 61.6+ 2. 4(88 ) Tarsus+ to e(mm ) 54.0+ 1.7 53.9+ 1.8 Weight (g),uncorr . 57.2+ 7. 2 54.3+ 7. 2(89 ) Weight (g),corr . 60.2+ 7.2(53 ) 56.9+ 7. 5(88 ) t=4.92). Twobird swer erecaptured ,on eadul tcaugh to n2 Apri l 1985(57. 5g ) andrecapture d on3 Apri l 1985ha dlos t3. 0g .On esecon d calendaryea r birdcaugh to n8 Februar y 1986(52. 0g )an drecapture d on6 Marc h 1986 had,eve nafte rthi slon gperio dlos t 1.6g .

9.2 Flight rangeestimate s Toestimat efligh t rangew ehav euse d theformul ao fDavidso n (1984):R = 95.447* S * (T 0,302 -M 0,302), where S= spee dkm/h ,T = tota lweigh ta t departure,M = fff-weigh to rtota lweigh ta tarrival .M (fff-weight)wa s

~~~~~~295 Bcoy MociLr~~~~~~

~~~~~~3 - • R f» o« •~~~~~~

~~~~~~2^ §•8°° o«|* o~~~~~~

~~~~~~1- 8 I * 8* • O • '•~~~~~~

~~~~~~o Ér* 1* O • 8 Î i II 1 1 1111~~~~~~

~~~~~~PLUMAÄE~~~~~~

~~~~~~S o . ..| • I » • M * «•• ° 1 êf - 8 g g o o • • w 1* o t * o8* o * I 1 1 Fl 1 1 . ... 1. i i i r i T i i 5/2 15/2 i8HSQ2a/Z 5Ö«*31*ff 2Q02S&2&S 4A <*fl\ WH*MHZt*M~~~~~~

Figure 9.8. The plumagean d bodymoul t ofCurle wSandpipe rcaugh ta t Iouik,Mauritani ai n 1985an d 1986(n=89 ,o adul t female, .adul t male,* 2nd c.y.).Th e birdsar eprovisionall y sexedwit hdiscriminan tfunctio n (see text). estimated fromdat ao nbird scollecte d inwinte ran dsprin g inMauritani a (Table9.1) ,Morocc o (Kerstene tal .1983 ,Va nBrederod ee tal .i nprep. ) andTunisi a (VanDij ke tal .1986) .Dat afro mbird sclearl ypreparin gfo r migration (thosewit hcorrecte dweight s> 60. 0g )ar eexclude d inthi s estimationbecaus esuc hbird sar eincreasin g thelea ncomponen to fthei r bodyweigh ta tthi stim e(Davidso n 1983).Th eaverag elea nweigh to f thesebird si s50. 8+2. 5 g (n=5).T oestimat e thetota lweigh ta t departurew eus eth emea nweigh t of 10%o fbird spreparin gfo rmigration : 73.7g (n=4).W eus eth efligh t speedgive nb yMcNei l (1972)fo r Sandpipers:8 0km/h .Thi swoul dgiv ea fligh trang eo f290 2k man dwoul d bring themfro mMauritani a toth enorther nhal fo fth eAtlanti ccoas to f Spain,t oth eMediterranea ncoas to fSoutheas t Spaino rthre equarter s thewa yacros s theSahar at oth eGul f ofGabès ,Tunisia .A non-sto p flightacros sth eSahar aha sbee nsuggeste d byWilso ne tal . (1980).A

296 colour-markedbir d caughti nMarc ho rApri l 1985a tIoui kwa ssee no n1 9 May 1985i nMalta .Th edepartur eweigh t fora non-sto p flight,380 0km , would predict tob e81. 7g .I tshoul db ementione d thatVa nBrederod ee t al. (1982)counte d 4000Curle wSandpiper s inth eMerj aZerga ,Morocco ,o n 30Apri l 1982,whil enon ewer epresen t on1 8Marc h 1982.I fbird sfirs t flyt oth eMerj aZerg a (2000km )an d thenfurthe rnort h (toth e Mediterranean)th edepartur eweight swoul db e65. 8g .Severa lbird shav e aweigh twel labov ethi sfigur ean dwil lprobabl yno tg othere .I ti s alsounknow ni fbird sfro mth eBan cd'Argui ng ot oth eMerj aZerg aa t all, theyma ycom efro mfurthe r souththa nth eBan cd'Arguin .

~~~~~~9.3 Plumagean dmoul t Upt o2 0Marc hmos tbird sar estil li nful lwinte rplumag ean dver yfe w birdssho wbod ymoul t (Fig.9.8) .Fro m theen do fMarc honwards ,an dwit h~~~~~~

~~~~~~&OOV MOULT 3- Ok~~~~~~

~~~~~~2- *• • ao•• »~~~~~~

~~~~~~1- • • o ooei • ••~~~~~~

** **tt«°* |**$f|e>*** ° •• _l L. -I I I 1 I L 1 1 1 1 I 1 U.

~~~~~~PUJM^ÄE s • o« • o«»~~~~~~

~~~~~~• •• •• •~~~~~~

~~~~~~W o * • o~~~~~~

~~~~~~o* «o • O» • •~~~~~~

~~~~~~• • oo o • •• •~~~~~~

W * *

~~~~~~1 1— i i i i i i i i i i i i i 1 1 1 <# 46 CO 54 5« 62 66 TO 7U. CORRECTE-O WEKiMT ,G~~~~~~

Figure 9.9. The relationship between plumage resp. body moult and corrected weight in Curlew Sandpipers caught at Iouik,Mauritani a in 1985 and 1986 (n=89, oadul t female, .adul t male,* 2nd c.y.). The birds are provisionally sexed with discriminant function (see text).

~~~~~~297 Table 9.3. Body moult of Curlew Sandpipers caught at Iouik, Mauritania, in spring 1985an d 1986.~~~~~~

~~~~~~Body moult 2nd c.y. Adult males Adult females All adults All birds~~~~~~

~~~~~~None (0) 29 5 10 15 44 Light (1) 4 8 4 12 16 Moderate (2) 1 8 7 15 17 Heavy (3) 1 9 2 12 13~~~~~~

~~~~~~Total 35 30 23 54 90~~~~~~

~~~~~~Table 9.9.4. Plumage of Curlew Sandpipers caught at Iouik,Mauritania , in spring 1985an d 1986.~~~~~~

~~~~~~Plumage (score) 2nd c.y. Adult males Adult females All adu Its All birds~~~~~~

~~~~~~Fullwinte r (1) 34 5 11 16 51 <50% summer (2/3) - 12 8 21 21 50% summer (4) 1 3 2 5 6 >50% summer (5/6) - 10 2 12 12 Full summer (7) - - - - -~~~~~~

~~~~~~Total 35 30 23 54 90~~~~~~

increasingweigh t (Fig.9.9) ,th eadul tbird sstar tthei rbod ymoul tan d changeint osumme rplumage .Non eo fth ebirds ,however ,reac hwha tw e considera complet e summerplumag e (score 7).Accordin g toou rhig htid e countsther ei sstron gemigratio ni nApril ,s obird sma ydepar twithou t havingreache d fullsumme rplumage . Toexamin eth erelatio nbetwee nplumage ,bod ymoul tan dweigh t independently oftime ,w edivide d theadul tbird scaugh t inApri lint oa low-weightgrou pan da high-weigh tgrou p (Fig.9.10) .Neithe rgrou p incorporatesnon-moultin g birds.Th elow-weigh t groupo fadul tbird s includesa hig hproportio no fbird si n(almost )ful lwinte rplumag e (scores 1an d 2)an dn obird si nnear-complet e summerplumag e (score6 , Fig.9.10) .Som ebird si n(almost )ful lwinte rplumag ehav ea bod ymoul t scoreo fone ,indicatin g that theyhav e juststarte d theirmoult .Th e highweigh tgrou po fadul tbird sinclude sa hig hproportio no fbird s

~~~~~~298 WEKSMT < 60& WEW5WT > 60 & BODV MOOLT~~~~~~

~~~~~~La *a« ^ J.4,5~~~~~~

Figure 9.10. The relationship between plumage and body moult in April for adult Curlew Sandpipers witha low weight,< 6 0g , (n-6)an d a high weight, > 60g , (n=22), expressed as relative surface over a body moult vs. plumage plot (BM 1= blank ,B M 2= vertica l stripes,B M 3= vertical plus horizontal stripes). whichar ehalfwa yint osumme rplumag e (scores3 ,4 an d 5). Someo fth e birdsi nalmos t fullsumme rplumag e (score 6)als ohav ea bod ymoul t scoreo fone ,indicatin g thatthe yar efinishin g theirmoult .Thi sagai n suggeststha tadul tCurle wSandpiper scomplet ethei rmoul t intoful l summerplumag efurthe rnorth .Ther ei sn oapparen tdifferenc ebetwee n adultmale san dadul tfemale si nth etimin go fth eacquisitio no fsumme r plumage (Fig.9.8) . Withon eexceptio nal lsecon dcalenda ryea rbird sstaye d inful l winterplumag e (Table9.4) .O fth esi xbird swhic hshowe d light,moderat e orheav ybod ymoul t (scores1 ,2 an d 3)fiv ewer estil li nful lwinte r plumage.I ti spossible ,therefore ,tha tsecon dcalenda ryea rbird si n Mauritaniad ono tchang e intosumme rplumag eunti la tleas t theen do f April (Fig.9.8) .

~~~~~~299 TT f~~~~~~

MarcelKerste n 10 Dunlin (Calidrisalpina ) 10.1Number san dmigratio n 10.1.1High-tid ecount s Thedat arefe r to 1985onl ysinc en ocount swer eperforme d in1986 .I n theBai ed'Aouati f 56085Dunlin swer ecounte d on2 3March .Thi si seve n moretha nth e4342 7bird scounte d inJanuar y 1980(Altenbur ge tal . 1981),suggestin g thata tmos tsmal lnumber so fDunlin sha dlef t theare a beforeou rarrival .Number sdecrease d throughoutApril ,bu t theactua l courseo fsprin gmigratio ndepartur ei sobscure db yth eirregula rpatter n of roost-siteoccupatio ni nth eeaster npar to fth eBai ed'Aouati f

~~~~~~24-3 19Ä5 )?-H i9S6 r>= 56 OÖ5 n« 22.163~~~~~~

~~~~~~• .£1000 • 1000 - 2000~~~~~~

~~~~~~• 2O00 - 4000 Q 4000 - sooo w > Sooo~~~~~~

~~~~~~Figure 10.1. Numbersan d distribution of Dunlin in the Baie d'Aouatif during high tide on three days in spring 1985.~~~~~~

~~~~~~300 NUM&ER.~~~~~~

~~~~~~4OO0-~~~~~~

~~~~~~JOOO~~~~~~

~~~~~~2000-~~~~~~

~~~~~~-1000-~~~~~~

~~~~~~2C/3 Xa 10/4 ÜOH 3QA \ots~~~~~~

Figure 10.2. Numberso fDunlin s during high tide inth eNorthwes tBa y in spring1985 . (Fig. 10.1).A serie so fregula rcount si nth eNorthwes tBa ygive sa betterpictur eo fth etimin go fsprin gmigratio ndepartur e (Fig.10.2) . Theresult ssugges t thatnumber sdecline d steadilyove rth estud yperio d

~~~~~~10OO- 2000~~~~~~

~~~~~~500- -»OO O 2000-4000~~~~~~

~~~~~~Figure 10.3. a_.Number so fDunlin s marked atdifferen t locationsi n the Baie d'Aouatif. b^.Proportio n ofmarke d Dunlin inth epopulatio na t different sites.~~~~~~

301 witha ninterruptio ndurin g thesecon dhal f ofApril .B yth een do fApri l 41%an d 44%o f theorigina lnumber si nth eNorthwes t Bayan d theBai e d'Aouatif respectivelyha d left thearea .Eve no n7 May ,38 %o fth e supposedwinterin gpopulatio ni nth eNorthwes tBa ywa sstil lpresent . Considering thever y longdistanc ebetwee n theBan cd'Argui nan dth e arcticbreedin g grounds (+550 0k mt oIceland) ,i tseem sunlikel ytha t thesebird sar eabl e toarriv e intim ei nth ebreedin garea .Thi swoul d meantha ta surprisingl y largeproportio no fth eDunlin swinterin go nth e Bancd'Argui nwil lno tparticipat e inreproductio ndurin g thenex t breedingseason .

~~~~~~Table 10.1. The age of Dunlins captured~~~~~~

~~~~~~Period Adults Juv«enile s Total % juveniles~~~~~~

~~~~~~1985 22-27 March 87 41 128 32 30March- 6 April 63 37 100 3T 10-18 April 113 66 179 37 21-23 April 10 15 25 6C~~~~~~

~~~~~~site 1 site 5 Period n Juv. % Juv. n Juv. 7- Juv.~~~~~~

~~~~~~1986 8 Feb.-14 March 153 74 48 72 19 26 2-12 April 18 11 61 122 47 39~~~~~~

~~~~~~Table 10.2. The proportion of juveniles in resightings of marked Dunlins in 1985.~~~~~~

~~~~~~Marked Observed~~~~~~

~~~~~~Period 22March- 4 April 10-19 April 20-29 April~~~~~~

~~~~~~Number 200 40 23 % Juveniles 37 50 70~~~~~~

302 10.1.2 Catches 1985 There were strong indications that more adults than juveniles left the area during the study period. First, the proportion of juveniles in the catches increased from 33%a t the end of March to 60%b y the end of April (Table 10.1). Further, the proportion of juveniles in resightings of Dunlins marked with plastic tape between 22Marc h and 4Apri l increased during the season (Table 10.2). This indicates that the majority of Dunlins that stayed on the Banc d'Arguin until late in the season are

~~~~~~Table 10.3. Numberso fadult san d juvenilestha tlef tth eBal ed'Aouati f between2 4Marc han d 25Apri li n1985 .* averag eo ftw oestimate s (18985 and 22152), seetext .~~~~~~

~~~~~~Adults Juveniles Total~~~~~~

~~~~~~1)N presen t2 4Marc h 35334 20751 56085 2)N presen t2 5Apri l 11076 20569* 31645~~~~~~

~~~~~~3)N departe d (1-2) 24258 182 24440 4) Zdeparte d (3/1) 69Z 1% 44%~~~~~~

~~~~~~Table 10.4. Concentrationo fbird smarke dbetwee n2 2Marc han d 4Apri l withinth epopulatio nclos et oth ecatchin garea sthroughou tApril .~~~~~~

~~~~~~Period samplesiz e numbermarke d %marke d~~~~~~

~~~~~~8-13Apri l 1822 26 1.4 15-20Apri l 448 9 2.0 22-27Apri l 1043 12 1.2~~~~~~

~~~~~~Table 10.5a. Biometriedat afo rDunlins ,1985 .~~~~~~

~~~~~~Adults(n-273 ) Juveniles (n=159) mean S.D. mean S.D.~~~~~~

~~~~~~Winglengt h (mm) 114.6 3.2 114.3 3.3 Billlengt h (mm) 30.9 2.7 30.4 2.6 Totalhea d (mm) 53.2 2.8 53.4 2.7 Tarsus+ to e (mm) 46.3 2.0 46.3 1.8~~~~~~

303 juveniles. It is even possible that hardly any juvenile Dunlin had left the area before the end of April. The estimated number of juveniles in the Baie d'Aouatif on 24Marc h is 0.37 x 56085 = 20751 birds.B y the end of April the proportion of juveniles had increased to 60-70% (Tables 10.1-2). Thus their number on 25Apri l was somewhere between 0.6 x 31645

~~~~~~FREQOEKJCy~~~~~~

~~~~~~25 2>2 9 315 35 5 3?3 3 S£ 27 » 31 S33 5 37 BILL LEMSTPH ,M M~~~~~~

~~~~~~Figure 10.4. Percentage Cumulative Frequency diagram of the bill length of a_.adul t Dunlin in 1985,t> .juvenil e Dunlin in 1985, c. adult Dunlin in 1986,d . juvenile Dunlin in 1986.~~~~~~

~~~~~~304 Table 10.5b. Biometrie data for Dunlins, 1986.~~~~~~

~~~~~~Adults (n=215) Juveniles (n=151) mean S.D. mean S.D.~~~~~~

~~~~~~Wing length (nun) IIA.4 3.2 113.9 3.7 Bill length (mn) 29.9 2.5 30.6 2.7 Total head (mm) 52.5 2.6 53.1 2.9 Tarsus + toe (mm) A6.6 2.0 46.6 1.8~~~~~~

- 18985an d 0.7x 3164 5- 2215 2birds .Base d onthi sinformation ,th e proportiono fadul tDunlin s thatlef tth estud yare aunti l 25Apri lca n beestimate d at 69%(Tabl e 10.3). Therewa sprobabl yn oimmigratio no fDunlin s intoth estud yarea . Arrivalo fne wbird swoul dhav eresulte d ina decreas eo fth eproportio n ofmarke dbird so fth epopulation .Ther ei sn osig no fsuc ha drop ,bu t thesituatio ni sa littl ecomplicate d sinceth emarke d Dunlinsdi dno t dispersefreel yove rth estud yarea .Instead ,th emarke d birdswer e concentrated closet oth esite swher e theywer ecapture d (Fig. 10.3). Whenw eus eth eresighting sclos et oth ecatchin g siteso f the20 0 Dunlinsmarke d between2 2Marc han d 4Apri li tca nb eshow ntha tthei r concentrationremaine dmor eo rles sconstan t throughout thestud yperio d (Table 10.4).

10.1.3Catche s198 6 NoDunlin swer emarke d in1986 ,bu t thedat ao nth eproportio no f juvenilesamon g thecapture d birdsshowe d thesam eincreas ea si n1985 . Thesituatio nwas ,however ,a littl emor ecomplicate d sinceth e proportiono f juvenilesdiffere d considerablybetwee n thetw osite swher e Dunlinswer ecapture d in198 6(Tabl e 10.1).

10.2Biometric s Tables 10.5aan d bprovid ea summar yo f thebiométri edata .I nal l measurements theMauritania nDunlin swer eappreciabl e smaller thanthos e caught inMorocc o inMarc h 1981(Kerste ne tal . 1983). Thisi sno t surprising sinceth eMorocca nDunlin sbelonge d forabou t 50%t oth e biggest subspecies C.a .alpina ,wherea s thevas tmajorit y ofDunlin si n Mauritaniawer efro m themuc hsmalle r subspeciesC .a .schinzi i (Table 10.6).

Î05 Table 10.6. Subspecific origin of Dunlins captured on the 3anc d'Arguin in 1985accordin g to plumage characteristics (Ferns iGree n 1979). Determination of subspecies vas only possible in bird= with summer plumage (n=2b7).

~~~~~~Adults Juveniles Subspecies number Z nunber %~~~~~~

~~~~~~C.a. alpina 2 1 - C.a. schinzii 206 87 21 68 C.a. arctica 4 2 - Arctica or sch inzii 24 10 10 32~~~~~~

Thefrequenc ydistributio no fbill-lengt h isclearl ybimodal ,a si s exemplified byth ePercentag eCumulativ eFrequenc y (PCF)diagram s(Fig . 10.4). Thisbimodalit yarise sfro mth efac ttha t femaleshav eo naverag e longerbill stha nmales .Fro mth epoin to finflexio ni nth ePC Fdiagra m itca nb ededuce d thatmale soutnumbere d females.I n198 5th eestimate d sexrati oi s6 8: 3 2i nadult san d 57 :4 3i njuveniles .I n198 6th e ratioswer e 70: 3 0an d 68 :3 2respectively . Theaverag ebill-lengt ho fmale san d femalesestimate d fromth ePC F diagram,ar ever yclos et opublishe dvalue so fth eIcelandi cbreedin g

~~~~Table 10.7. Average bill lengths of male and female Dunlins captured inMauritani a compared with those of C. a. schinzii breeding in Iceland (Morrison &Wilso n in Pienkowski & Dick 1975).~~~~

~~~~~~Origin Bill length (mm)~~~~~~

~~~~~~males females mean S.D. mean S.D.~~~~~~

~~~~~~Iceland adults 28.4 1.3 32.8 1.1~~~~~~

~~~~~~Mauritania adults 1985 28.5 1.6 33.1 1.7 1986 28.6 1.8 32.8 1.6~~~~~~

~~~~~~juveniles 1985 28.4 1.6 32.9 1.2 1986 28.9 1.6 34.0 1.4~~~~~~

30b populationo fC .a .schinzt l(Tabl e 10.7). Iti sver yconvenien t that therei slittl eoverla pbetwee nth ebill-length s ofmale san d females.B y allocatingbill-length s_ <30. 5m m tomale san dbill-length s^ >31. 5m mt o females,mor etha n80 %o fth ebird scapture dcoul db eassigne d asex , withonl ya fe werror s (Table 10.8). Femalesd ono tonl yhav elonge rbill stha nmales ;the yar egenerall y biggeri nal lmeasurement stake n(Tabl e 10.9).

~~~~~~Table 10.8.Proportio n of male and female Dunlins with 'short'an d 'long'bills .~~~~~~

~~~~~~1985 1986 Age and sex bill length (mm) bill length (mm) _<30. 5 231 -5 <30 -5 131 -5~~~~~~

~~~~~~Adults males 89% 3% 85% 5% females 5% 85% 5% 83%~~~~~~

~~~~~~Juveniles males 90% 3% 84% 5% females 3% 86% 0.5% 97%~~~~~~

~~~~~~Table 10.9.Averag e measurements of male (bill length < 30.5mm )an d female (bill length_ >31. 5mm )Dunlins .~~~~~~

~~~~~~Adults Juveniles~~~~~~

~~~~~~males females males females mean S.D. mean S. D. mean S.D. -ean S. D.~~~~~~

~~~~1985 (n) (165) (90) (87) (64) Wing length 113.1 2.8 117.0 2. ,6 112.7 2.5 116.4 3. ,0 Total head 1. 51.3 1.5 56.4 1, .5 51.4 1.4 56.1 1. ,3 Tarsus + toe 45.4 1.6 47.8 1, .6 45.4 1.2 <-".5~~~~

~~~~1986 (n) (142) (57) (87) (48) Wing length 113.2 2.7 117.2 2 .7 112.6 3.2 ::?.6 3. ,2 Total head 1. 51.0 1.4 56.0 1 .8 51.1 1.3 56.6 1 .9 Tarsus + toe 46.0 1.9 47.9 1 .6 45.8 1.5 -3.0 1. .6~~~~

307 10.3 Preparation for spring departure 10.3.1. Moult of body feathers Many Dunlins were actively moulting their body feathers during the study period. By the second half of April 1985 87%o f the adults and 27%o f the juveniles were in full summer plumage (Fig. 10.5). This indicates that the spring moult of juveniles lays behind that of adults. In fact the first juveniles and the last adults started tomoul t the samemoment , i.e. the end ofMarch . In 1985,3 7ou t of 41 juveniles captured between 22an d 27Marc h were still inwinte r plumage. The other 4 juveniles had some 25%summe r plumage. Some 20day s later, i.e. between 10an d 15April ,th e very first juveniles in full summer plumage appeared in the population.Amon g the adults captured between 22an d 27March , 7ou t of 87bird s (8%)wer e still inwinte r plumage.Al l but one of these birdsha d just started to moult. Between 16an d 22April , 13%( 7ou t of 53 birds)ha d not yet completed their moult,althoug h theywer e all in the final phase. Combining the information on adults and juveniles it can be deduced that themoul t from winter plumage into summer plumage takes about one month in both age classes. There was also a difference in the timing of the prénuptialmoult

Table 10.10. The occurrence ofmale s (bill length < 30.5mm )an d females (bill length_ >31. 5mm )amon g 87adul t Dunlins captured between 22an d 27March , according to their plumage.Th e majority of the birds (n=64)ha d an intermediate plumage. *Assumin g a sex-ratio of 68 :3 2 (see figure 9.10.4).

~~~~~~Winter plumage Males Females~~~~~~

~~~~~~n observed 1 5 n expected * 4.08 1.92~~~~~~

~~~~~~x = 7.26, p > 0.01~~~~~~

~~~~~~Summer plumage~~~~~~

~~~~~~n observed 14 1 n expected * 10.20 4.80~~~~~~

~~~~~~x" = 4.42, p < 0.05~~~~~~

~~~~~~308 FREQUENCY ADMITS 1Mtf JUVENILIS 1M6 22- 2*/J~~~~~~

~~~~~~,n , 3b/S-£* DrJS X~~~~~~

~~~~~~H ^ a~~~~~~

~~~~~~r-^iIM . iê/n -22A i n=4 2~~~~~~

4o 50 6o 70 30 40 50 60 BODV WEIGHT, 6 betweenadul tmale san d females.Amon g theadult scapture d between 22an d 27March ,female sdominate d thebird stha twer estil li nwinte rplumage , whereas theywer eunderrepresente d among thebird s thatwer ealread yi n fullsumme rplumag e (Table 10.10).Thi sindicate s thatfemale s startedt o moult later thanmales .

~~~~~~309 FREQUENCY ADULTS \ô86 JUV/EKHLES 1386~~~~~~

~~~~~~S- 13/2 «-13/2~~~~~~

~~~~~~-\o - hrL. 6-1^4/3 6-ia/3~~~~~~

~~~~~~2o JT-,~~~~~~

~~~~~~"KD rL 4- 12/4 0=. S? 20~~~~~~

~~~~~~,-T 1 in 50 JO 40 5o A) «OCV WE1ÛMT , CS~~~~~~

Figure 10.5. Frequency distribution of body weight for different periods for a_.adul t Dunlin in 1985,_b . juvenile Dunlin in 1985, £. adult Dunlin in 1986,d_ .juvenil e Dunlin in 1986.Shade d areas denote birds in full summer plumage.

10.3.2 Bodyweigh t Figure 10.5a t od ,sho wth efrequenc ydistributio n ofbod yweight .I n bothadult san d juveniles theaverag ebod yweigh t increased,bu tth e increase inadult swa smuc h larger (Table 10.11).Thi sweigh t increasei s

~~~~~~310 Table 10.11. Average body weights of adult and juvenile Dunlins in the course of spring.~~~~~~

~~~~~~Body weight (g)~~~~~~

~~~~~~adults juveni les mean + S.D. (n) mean + S.D. (n)~~~~~~

~~~~~~1985 22-27 March 44.8 -.3 (87) 39.3 4.2 (41) 30March -6 April 48.8 6.7 (62) 40.8 5.4 (38) 10-15 April 53.9 5.3 (70) 42.3 6.2 (37) 16-22 April 53.8 7.1 (52) 43.1 7.2 (42)~~~~~~

~~~~~~1986 8-13 Feb. 38.9 3.4 (34) 36.7 6.3 (49) 6-14 March 42.3 3.9 (99) 39.1 3.7 (44) 4-12 April 47.4 5.3 (82) 38.6 4.6 (58)~~~~~~

mainlydu et ofa tdepositio n (seechapte r 8)an dillustrate s thatthes e birdsar epreparin g themselvesfo ra lon gmigrator yflight .Th e differencebetwee nadult san d juvenilesmus tb erelate d toth efac ttha t thejuvenile sdi dno tleav eth estud yare abefor eth een do fApril , whereasman yo f theadult sdeparte d (Table 10.3).

10.3.3 Adults Adultswhic hhav ecomplete d theirmoul tar egenerall yheavie r thanthos e whichwer estil lmoultin g (Table 10.12), butthi sdoe sno tmea n thateac h birddelaye d premigratory fatteningunti lmoul twa sfinished .Th ebod y weighto fbird swit hmoul tstil li nprogres sincrease d aswel love rth e studyperiod . Dunlinshav ea ver ylo wweigh tbefor eth eonse t ofmoul tan d therei s a strongpositiv ecorrelatio nbetwee nbod yweigh tan dbill-lengt h (Table 10.13). Aroug hestimat e forth eamoun t offa ttha ti sdeposite dbefor e thestar to fth esprin gmigratio nmigh tb ederive d fromth edifferenc ei n bodyweigh tbetwee nsumme ran dwinte r plumagebirds .Thi sweigh t difference isi norde ro f 10-14grams ,an d therei sa tendenc y forbi g birds toaccumulat emor ereserve s thansmal lbirds . Oneimportan t point remains tob emade .I ti sno t only theaverag e bodyweigh t ofadul tDunlin stha tincrease s inth ecours e ofth eseason ,

~~~~~~;l1 Table 10.12. Body weights of adult Dunlins according to their stage of moult.~~~~~~

~~~~~~Body weight (g)~~~~~~

~~~~~~winter intermediate summer plumage plumage plumagt mean S. .D. (n) mean S.D. (n) mean S.D. (n)~~~~~~

~~~~~~1985 22-27 March 44.9 4.3 (70) 45.4 3.9 (16) 30March- 6 April 46.1 5.6 (35) 52.5 6.5 (26) 10-15 April 52.9 6.7 (27) 53.8 3.5 (36) 16-22 April 53.0 6.5 ( 6) 54.0 7.1 (44)~~~~~~

~~~~~~1986 8-13 Feb. 38.9 3. ,4 (34) 6-14Marc h 41.2 4. ,1 (22) 42.6 3.8 (77) 4-12 April 45.8 5.2 (48) 50.3 4.9 (28)~~~~~~

but themaximu mbod yweight swer emuc hhighe rb yth een do fApri ltha n theywer eb y theen do fMarc h 1985(Fig . 10.5).Thi simplie s that,i f adultDunlin sdepar tfro m theare ab yth een do fMarc h (asi sa tleas t suggested byfigur e 10.2,the yd os owit ha muc hlowe rbod yweigh ttha n theirconspecific swhic hsta yunti l theen do fApril .I fthi sweigh t difference,whic hamount st osom e 10g ,i sentirel ydu e tofat ,th e potentialfligh trang eo fbird stha t stayedunti lth een do fApri li si n theorde r of 1000k mlonger .Consequently ,thes elat ebird shav e tous e fewerstopove rarea sdurin g their springmigration .T osom eexten tthe y maycompensat e thiswa yfo rth etim ela gbetwee n theman d theearl y departingbirds .

10.3.4 Juveniles Thefirs t juvenileDunlin scomplete d theirmoul tafte rApril . Incontras t toth eadults ,wher emale sstarte d tomoul tearlie rtha n females,thi ssequenc ewa sreverse damon g juveniles (Table 10.14).Ove r 50% ofth ejuvenil emale sha dno teve nstarte d tomoul tb yApril .I n

31; Table 10.13. Linear regression equations for the relation between body weight (g)an d bill length (mm)i nadul t Dunlins. In summer plumage birds the slope of the regression equation is significantly steeper than in winter plumage birds (p<0.5,Studen t t-test). Only one adult with winter plumage was captured in 1985.

~~~~~~Plumage year Bodyweigh t *= r S.E. of a a (bill length)+ b~~~~~~

~~~~~~Winter 1986 1.05 BL+ 7.84 0.62 55 0.11~~~~~~

~~~~~~Summer 1986 1.51 BL+ 5.76 0.60 28 0.24 1985 1.61 BL+ 4.19 0.39 122 0.18~~~~~~

~~~~~~Table 10.14. Proportions of male and female juvenile Dunlins captured between 10an d 22Apri l at different stages ofmoult . 3 birds could not be sexed according to their bill length.~~~~~~

~~~~~~Plumage Males Females n % n %~~~~~~

~~~~~~Winter plumage 22 51 7 21 Intermediate 15 35 20 58 Summer plumage 6 14 7 21~~~~~~

~~~~~~Total 43 34~~~~~~

~~~~~~Table 10.15. Body weights of adult and juvenile Dunlins that had completed their bodymoult . a) Juveniles captured between 10an d 22April . b) Adults captured between 16an d 22April .~~~~~~

~~~~~~Males Females mean + S.D. (n) mean + S.D. (n)~~~~~~

~~~~~~Juveniles a) 45.9 + 4.8 (6 ) 54.8 + 7.6 (6 ) Adults b) 49.7 + 5.3 (25) 59.6 + 5.1 (18)~~~~~~

313 females this figure was only 21%.Moreover , the proportion of females that had completed their moult between 10an d 22Apri l was higher in females than inmales . The body weights of juveniles with completed moult was on average some 5 g below that of adults (Table 10.15). This indicates that these birds may leave the Banc d'Arguin together with the last adult females.I f there really is a surplus of males in theadul t population (as is suggested by the sex-ratio in our catches), the juvenile females will have a fair chance to breed during their first summer.

10.4 Conclusions 1.Th emajorit y of Dunlins that had spent the winter on the Banc d'Arguin were still present by the end ofMarch .Abou t one third of these birds were juveniles, the restadults . 2. By the end of April,n o juveniles and some 70%o f the adults had left the study area. 3.Accordin g to theirmeasurement s and plumage characteristics, the vast majority of Dunlins on the Banc d'Arguin belonged to the subspecies Calidris alpina schinzii. 4.Male s outnumbered females inbot h adults and juveniles; sex ratios were 68 :3 2an d 57 :4 3 respectively. 5.Moul t into summer plumage took about onemont h inadult s and juveniles,bu t juveniles lag about onemont h behind theadults . 6. Among adults,male s started tomoul t earlier than females. In juveniles, this pattern is reversed. 7. The body weights of both adults and juveniles increased over the study period, but the increase in adults was much larger. 8. Juvenile females are more likely to participate in reproduction than juvenilemales . 9. Adult Dunlins that leave the Banc d'Arguin early in spring (end of March-beginning of April)depar t with a lower bodyweigh t than birds that leave by the end of April.B y using fewer stopover areas during their spring migration these late birds may compensate to some extent for the time lag between them and the early departing birds.

314 TheunisPiersm a 11Bar-taile d Godwit (Limosalapponica ) 11.1 Biometry Bar-tailed Godwitsar ea sexuall yver ydimorphi cwade r specieswit h femalesbein glarge r thanmale s (Green 1973).Thi si sals oapparen ti n ourdat ao nbil llength sfo rbird scapture d onth eBan cd'Argui n(Fig . 11.1).W ecapture d farles sfemale s thanmal eBar-taile d Godwits (27%vs . 73%),whic hi si naccordanc ewit ha nunequa lse xrati oo f 1:2recorde di n January/February 1980b yvisua lobservation s (Piersma 1982).Tabl e11. 1 showstha tals oi nothe rmeasurement smale sar esmalle r thanfemales . Juvenilemale sar esomewha tsmalle r thanadul tmale san dmuc hlighter . Thelatte rindicate s thatjuvenil ebird sd ono tgenerall ydeposi tfa t reservesfo rsprin gmigratio nan dma ytherefor eb eexpecte d tospen d their secondcalenda ryear' ssumme ro nth eBan cd'Arguin .A si sapparen t fromtabl e 11.2,al lmeasurement sar estrongl yan dpositivel ycorrelate d

Table 11.1.Bod ymeasurement so fBar-taile dGodwit so nth eBna c d'Arguin inFebruary-Apri l1985/86 .Male sar ebird swit hbill s smallertha n8 9am .Bod ymas svalue swer ecorrecte d formas slos s aftercapture .Linea rmeasurement si nmm ,masse si ngram .

~~~~~~Males Males Females Juveniles (n=23) Adults(n=61 ) Adults~~~~~~

Vinglengt h 205.0 5.2 214.2 6.3 230.7 4.0 Billlengt h 78.2 3.9 78. 1 3.6 99.8 4. 1 Totalhea d length 114.1 3.7 115.2 5.0 137.9 4.7 Tarsusplu sto e 87.3 2.6 87.2 3.0 95.0 2.6 Bodymas s 204.9 22.8 294.4 41.6 355.4 45.6

~~~~~~315 PlSES^JMED MALES PRESUMED *=HMALES~~~~~~

~~~~~~ÓO 66 9o 96 9o 96 eo 96 lOO 405 -MO MS "B4LL LENÖW.MM~~~~~~

~~~~~~Figure 11.1. Frequency distribution ofbil l lengths ofBar-taile d Godwits captured onth eBan c d'Arguin in 1985/86 (adult birds only).~~~~~~

~~~~~~BAR-TAILED «SCOWITS~~~~~~

235 &*0 WING LENGTH, MM Figure 11.2. Frequency distribution ofwin g lengths ofadul t Bar-tailed Godwits captured onth eBan c d'Arguin. Birds indicated with hatched bars have been categorized asfemale s onth ebasi s ofbil l length (bill >89 ,Fig .9.11.1) .

~~~~~~KttJMB^R & BttR-TAILED «SCCWlTS~~~~~~

~~~~~~9o 85 SO 96 A00 TARSUS "PLUS TOE LENGTH,M M~~~~~~

Figure 11.3. Frequency distribution ofth elength s oftarsu s+ to eo f Bar-tailed Godwits captured onth eBan c d'Arguin. Birds indicated with hatching were categorized asfemale s since their bills were larger than 89m m(Fig .9.11.1) .

31.6 Table 11.2. Pearson correlation coefficients between different body measurements ofBar-taile d Godwits captured inMarc h andApri l 1985 (sex and ageclasse s combined)n=85 .Al lcoefficient s aresignifican t atth e 0.001 level.

~~~~~~Wing Bill Total head Tarsus+ to e~~~~~~

~~~~~~Weight 0.748 0.599 0.362 0.339 Wing 0.753 0.493 0.560 Bill 0.520 0.645 Total head 0.350~~~~~~

~~~~~~MASS LOSS ftETVJEBü WEIcSKlNöTS /< s JO o 2?- *4 -~~~~~~

~~~~~~11 - o |o/ 18 °r°jr 15 O O & 13 o .f- 3 ° ? o~~~~~~

~~~~~~- o 6 'o o o/ 08 3 - o o o O i I i 1 1 1 1 1 1 1 1 1 O 1 2J*4ff6?094o MOOR TIME BETWEEN FIRST AND SCGOWO VIEI6UIN6 PERCENTAGE~~~~~~

~~~~~~2 3 4 5 6 1 S9 10 HOUR TIME "BETWEEN CAPTURE AMD F\Rsr VJEJGO-dNUS~~~~~~

~~~~~~Figure 11.4. Mass loss after capture (top)an dth etin e between capture andfirs t weighing (bottom)o fBar-taile d Godwits onth eBan c d'Arguin. Sexan dag eclasse s combined.~~~~~~

~~317 witheac hother .Despit e thegoo dcorrelations ,th esiz efrequenc y distributions ofwin g lengths (Fig. 11.2)an dtarsu s+ to elength s(Fig . 11.3)o fpresume d malesan d females showa goo doverlap .~~

11.2 Bodymas schange s Masslosse safte rcaptur ear eshow ni nfigur e 11.4.Bar-taile d Godwits losto naverag e 1.9g/ hafte rcapture ,an dwer eweighe d onaverag e 3.3 hoursafte rcaptur e (i.e.a naverag emas slos so f6. 3 g). Figure 11.5 shows thetransforme d bodymasse so fth ecapture d Bar-tailed Godwitsi n relation todate .Ther ei sa gradua l increase inbod ymas sove rth e entire studyperiod ,bu tsom ever yligh tbird swer ecapture d after 15 April.Thes ebird scoul dpossibl y represent immigrants frommor esouther n winteringareas ,suc ha sGuinea-Bissa uwher e some 150,000Bar-taile d Godwitsar eno wknow nt ospen d thewinte r (Zwarts 1984).Ove ral lbird s (alsotakin g thelat eligh tone sint oaccount) ,th eaverag eincreas ei n 2 2 bodymas si s1.8 4g/da y (r=0.20 )fo rmale san donl y0.6 7g/da y( r=0.01 )

~~~~~~BOOYMASS ,~~~~~~

~~~~~~O • , O , D « 9 4co •,»,•. a* o • ' r!0 36o - X' '~~~~~~

~~~~~~310~~~~~~

~~~~~~' * O 260 -~~~~~~

~~~~~~• • 24o - • •~~~~~~

~~~~~~200 ^ • •~~~~~~

~~~~~~160 - • i i FEBÏ*-!A«.y MARCH APRtL~~~~~~

Figure 11.5. Body masses of adult Bar-tailed Godwits on the Banc d'Arguin in relation to date.Male s are birds with bills < 89mm . Dots and circles are birds caught in 1985, triangles are data excluding the birds with very low body niasses captured after 15Apri l and indicated with small sumbols.

~~~~~~318 PEftCEKtTAÄE Dr 10 28 AOO su WINTER PlXiMAfiE 80 1 C^JAOTE« SOMMER 60~~~~~~

~~~~~~TMKEE--QUARTER ::::::: ••»•••• 20 •••••*• B*•••••• FUU_ STUMMER VLUMM3E o -too MEDIUM aooy MO£iLT~~~~~~

~~~~~~80 uest^r aocy MOULT 60 40 NO BOOV MOULT 10 o 11111111111111niniiii i 11111111m i 11111 MII1111 1i n 30/3-4/U 9-H5/M 16--<ÔA4~~~~~~

Figure 11.6. Development of summer plumagean d bodymoul t ofmal e Bar-tailed Godwits on the Banc d'Arguin in thecours e ofApri l1985 . forfemales ,bu tbot hvalue smus tb eunderestimates .I fw eexclud eth e datafo rth eligh tan dpossibl y immigrantbird s (seebelow) ,male s increased bodymas sb y2. 5g/da yan d femalesb y2. 6g/da y (asindicate d by thefitte d linear regressions infigur e 11.5).Bot hvalue sar emuc h smallertha nth erat eo fbod ymas sincreas eo f6- 8g/da yi nth esam e godwit populationi nFriesland ,Th eNetherland s inMa y 1985-86 (Piersma& Jukema,i nprep.) .

11.3 Plumagean dmoul t Figure 11.6show sth etempora lchange si nth eexten t ofsumme rplumag e and theintensit y ofbod ymoul t inmal eBar-taile d Godwits insprin g 1985. Inth ethir dperio d theproportio no fbird si nful lsumme rplumag e hasdecline dan d theproportio no fbird si nwinte rplumag eincreased . Thissupport s thesuggestio n thatsom eunmoulte d birdsarrive dand/o r thatbird si nful lsumme rplumag edeparte d fromth earea .Th epercentag e ofBar-taile d Godwitswithou t bodymoul t steadily increased overth e spring season.Th edat a suggest that (male)Bar-taile d Godwits leaveth e Bancd'Argui nwit ha three-quarte r orfull ycomplete d summerplumag ean d nobod ymoult .

319 Piet Duiven 12 Whlmbrel (Numenius phaeopus) 12.1 Catches 1985. In total we caught twenty-seven Whimbrels. Twenty-one birds were cannon-netted inth eNorthwes t Bayo n9 April 1985.Th eothe r six were caught inmis t nets at locations onth emudflat s near theai rstri pan d opposite thecam p site on different dates inMarc h andApril . Twenty of the Whimbrels were after second calendar year birds, and seven were in their second calendar year.

~~~~~~1986. Four Whimbrels were caught near thecam p site on various dates in March andApril . Theag eo f thebird s wasafte r second calendar year.~~~~~~

12.2 Biometrics The twoag eclasse s were separated forcalculation s of mean, s.d.an d range of thevariou s measurements andweight s (Table 12.1). Because of the overlap inth edat a thecatchin g were combined.

~~~~~~Table 12.1. «himbrel,Ban cd'Arguin ,Mauritania .Weigh ti ng .Win g length,bil llength ,tota lhea d (=tohe)an d tarsus+ to e(=tato )i nmm .~~~~~~

~~~~~~2ndcalenda ryea r >2n dcalenda ryea r Mean S.D. (n) Range Mean S.D. (n) Range~~~~~~

Weight 407.C 25.56 (7) 380 -440 528.9 45.95(20 ) 445 -610 Wing 253.4 6.40 (7) 245 -264 263.3 7.65(24 ) 251 -283 Bill 83.96 5.23 (7) 73.8-90. 0 84.29 5.08(24 ) 75.5-93. 0 Tohe 124.1 4.54 (7) 114.7-129.0 124.4 5.97(24) 114.9-135.8 Tato 105.C 2.16 (7) 101 -108 105.5 4.46 (24) 97 -114

32 0 Forcomparin g theweight so fth etw oag eclasse sonl y thecatche so f198 5 wereused .Bird safte r theirsecon d calendaryea rha d significantlyhighe r weights thanth esecon d calendaryea rbird s (Analysiso fvariance ,F«=43.78 , P<0.001). Theweight so f theWhimbrel scaugh ti n198 6wer e369 ,406 ,45 9 and 630g .Fo rcompariso nonl yfe wdat ao nweight sfro mwinte rquarter sar e available.I nSout hAfric ai nlat eMarch/earl yApri l twoadult sweighe d 627

~~~~~~TOTAL WCAD , MM •140~~~~~~

~~~~~~- *yS ^^~~~~~~

~~~~~~IJO~~~~~~

~~~~~~0 A A O O 120 SA A o iMD CAL.yp ~^^°^"^ A >awo CAL. yfl.~~~~~~

~~~~~~110 ' l — J . .. L I I I 9o Sü SO 1O0 »ILL. l_EH«TH ,M M~~~~~~

Figure 12.1. Relationship between bill length and total head of Whimbrels at the Banc d'Arguin (Mauritania). ForWhimre l 2nd c.y.: y = 58.5879 + 0.779964 x, r=0.898683; forWhimbre l > 2nd c.y.: y = 29.2278 + 1.12869 x, r=0.960326. and 600+g an da juvenil e 370g (Glutzvo nBlotzhei me tal . 1977).Fou r adultsbird safte rcompletio no fwin gmoul tweighe d between 480an d 600g at theBan cd'Argui n inNovembe r (Dick 1975). Themea nwin glengt ho fth ebird safte rsecon d calendaryea ri slarge r thantha to fsecon dcalenda ryea rbirds .Th edifferenc ei ssignifican t (Analysiso fvariance ,F=8.58 ,P<0.001) . Birdsi nbot hag eclasse shav e longerwing s thanha sbee ndescribe d inliteratur e (Glutzvo nBlotzhei me t al. 1977,Prate re tal .1977 ,Cram p& Simmon s 1983).Howeve rmeasurement s inthes ereference sar emostl y obtained frommuseu mspecimens ,an dbecaus e ofpost-mortu m shrinkagewin g lengthi ndrie dmuseu m skins issignificantl y shorter thani nfreshl ykille d orlivin g birds (Pratere tal .1977 , Engelmoere tal . 1983).Afte rtransformatio nth edat afo rshrinkage ,th e estimated winglength s inou rWhimbrel sar estil l longer.Th ewin glength s ofadult scaugh ta t theBan cd'Argui n inNovembe rwer eals osmalle r thani n

32] our birds (Dick.1975) . Although wing moult was complete, the primaries possibly still were not full grown at that moment. Though the differences are not statistically significant, bill, total head and tarus + toe tend to be larger in the birds after second calendar year. A fairly close relationship has been found between bill length and total head.Whe n only one of these measurements isavailabl e the second one can be estimated by comparison with figure 12.1.A s we only have measurements of tarsus + toe,w e unfortunately can not calculate the relationship with the single tarsus for the same purpose. The geographical origin of theWhimbrel s at the Banc d'Arguin is not clear. As far asw e know the birds belonged to the nominate phaeopus,th e breeding birds of Iceland -Wes t USSR. The Islandic population of this race on average has the longest wings and may be considered for the wintering Whimbrels at the Banc d'Arguin, although there isn ohar d evidence yet. Greater samples and more comparative biométrie data from different breeding and wintering areas will be essential for statictical analysis.Moreove r ring recoveries or sightings of colour marked birds will help to clarify which breeding population is represented on the Banc d'Arguin.

322 TheunisPiersm a 13 Redshank.(Tring atotanus ) Thesprin gmigratio n (departure)o fRedshank swa salread y inful lswin g byth etim ew estarte dou rcatchin gactivitie so nth eBan cd'Argui ni n 1985.Fro m2 4Marc ht o1 7Apri l 1985Redshank ,number saroun dIoui k droppedwit h6 8% fro m287 8t o96 5birds .Thei rrelativel yearl y departurema yhav ebee non eo fth ereason stha tw ecapture d onlyfe w(29 ) Redshanksdurin g thisexpedition .I n198 6catchin gactivitie salread y started inearl yFebruar yan ds oa smal lsampl eo fbird swa sobtaine d frombefor eth etim eo fmas sdeparture .Th eaverag emeasurement so f Redshanksar epresente d intabl e13.1 .Apar tfro mbod ymass ,th e biométrievalue s (bothaverage san dstandar ddeviations )closel yresembl e thoseo fbird scaugh t inMorocc odurin gsprin gmigratio n (Table 13.2), suggesting thatw ear edealin gwit hth esam epopulation .Thi si sprobabl y thepopulatio nbreedin g inNorthwes tEurop e (TheNetherlands ,Wes t Germany,Denmark) ,a si ssupporte d byth esightin go fa colou rmarke d

~~Table 13.1. Bodymeasurement so fRedshan ko nth eBan cd'Argui ni n February-April 1985an d 1986.Bod ymas svalue sar eno tcorrecte d forlos s aftercapture .Linea rmeasurement s inmm ,bod ymas si ng .~~

~~~~~~Juveniles (n=12) Adults (n=32) Allbird s(n=45 ) average+ S.D . average+ S.D . average+ S.D . (min.-max.) (min.-max.)~~~~~~

Winglengt h 157.1 3.9 161.3 3.5 160.2 4.0 (150-164) (154-168) Billlengt h 43.2 1.8 43.7 1.5 43.5 1.6 (40.1-45.7) (40.2-47.5) Totalhea d length 74.9 2.5 75.6 1.7 75.4 1.9 (71.0-79.2) (71.9-79.4) Tarsus+ to e 84.8 2.8 85.1 2.7 85.0 2.7 (80-89) (79-92) Bodymas s 100.8 18.4 129.7 18.3 122.0 22.1 (86-150) (95-174)

32 Table 13.2. Comparison between the measurement of adult Redshanks on the the Banc d'Arguin and at Sidi Moussa,Morocco ,durin g spring migration (February-April vs.March) . The latter data were taken from Kersten & Piersma (1983).

~~~~~~Banc d'Arguin Sidi Moussa Mauritania Morocco average + S.D. average +_ S.D.~~~~~~

~~~~~~Wing length (mm) 161.3 3.5 162.0 3.9 Bill length (mm) 43.7 1.5 43.5 1.7 Total head length (mm) 75.6 1.7 75.5 1.8~~~~~~

~~~~~~Body mass 129.7 18.3 110.2 13.7~~~~~~

Table 13.3. Pearson correlation coefficients between different body measurements of Redshanks (all age classes), n=30. Coefficients significant at the 0.05 level are underlined and those significant at the 0.001 level bold typed.

~~~~~~Wing Bill Total head Tarsus + toe~~~~~~

~~~~~~Body mass 0.571 0.182 0.304 0. .222 Wing 0.181 0.345 0. ,307 Bill 0.856 0. .512 Total head 0. ,609~~~~~~

~~~~~~Table 13.4. Incidence of body moult in juvenile (J)an d adult(A) . Redshanks on the Banc d'Arguin in February-April 1985 and 1986.~~~~~~

~~~~~~February March April~~~~~~

~~~~~~No moult J 80% 100% 75% A 50% 76% 100% Light body moult J 20% 25% A 50% 19% Medium body moult J A 5%~~~~~~

~~~~~~Number of birds J 3 examined A 21~~~~~~

~~~~~~32 4 BODY MASS , G~~~~~~

~~~~~~440~~~~~~

~~~~~~•IAO ADULTS •~~~~~~

•

~~~~~~• •~~~~~~

~~~~~~• • • • !f * —» • • •~~~~~~

no • » m • • 400 \ 1 TG&ZOM& 1 MAQC« 1 *PfctL Figure 13.1. Changes in body mass of juvenile and adult Redshanks on the Banc d'Arguin in 1985an d 1986.Thi n lines connect successive weighings of individual birds. The linear regression of first taken body masses against data is given for adult birds.Fo r juveniles the positive slope (0.25 g/day)wa s significantly different from zero.

Redshanko nth eislan do fPellwor m(Wadde nSe ao fSchleswig-Holstein) , wherei twa sspotte da sa breedin gbird ! Bodymas scorrelate d bestwit hwin glength ,bu thardl y sowit hth e otherlinea rdimension s (Table 13.3).Bill ,tota lhea dan d tarsus+ to e lengthar estrongl ycorrelate dwit heac hother ,bu tmuc hles ss owit h winglengt han dbod ymass .Thi sma yindicat etha tonl ywin g lengthi sa measureo fstructura l size,th eothe rdimension s probablybein g expressions ofrace ,se xan dage . Wemad eonl ya fe wmeasurement s ofmas slos safte rcapture ,an dfo r thisreaso nbod ymas swa sno tcorrecte d forth etim ebetwee ncaptur ean d firstweighing .Th eaverag e timebetwee ncaptur ean dfirs tweighin gwa s

325 3.26 h (S.D.=1.53; extremes 0.6-7.3). Juveniles were on average much lighter than adults suggesting that large numbers of second calendar year birds summer on the Banc d'Arguin. However, figure 13.1 shows that some juvenile birds do reach higher body masses in April, and might therefore leave the area for the north. The adults show a continuous increase in average body mass over the study period. A linear regression suggests an average body mass increase of 0.37 g/day. This estimate is not affected by (e.g. very low) body masses of birds remaining or arriving after the mass departure in early April. One individual bird recaptured after two days in the first week of April showed a 4 g increase in body mass. Another bird recaptured after four days in early February lost 10 g. Juvenile birds showed very little body moult throughout spring (Table 13.4). Adults showed some body moult in February and March, but not in April. This indicates that the birds migrate without growing body feathers.

32 6 Bruno J.En s 14 Turnstone (Arenaria interpres) 14.1 Materials and methods The large majority of Turnstones were caught at high water with clap nets in the little village of Iouik, while they were feeding on drying fish and litter left onth ebeach . Some were caught with a cannon neti n Iouik and a fewint o mist nets placed on themudfla t nearby. Separating theTurnstone s in adults and juveniles, using the criteria of Prater et al. (1977), wasgenerall y easy except fora few individuals. In some measurements these individuals tended more to adults, in others more to juveniles (Table 14.1), indicating they might well be immatures in their third calendar year. Itwa s decided to restrict theanalysi s to the adults and juveniles. A fewtime s birds were reweighed after a certain time lagt o estimate the weight loss incurred. Despite a large scatter (after 8 hours individuals lost from 1t o 5g in weight), a significant non-linear

Table 14.1. Comparisono fbiométri edat ao nbird so fthre edifferen t ageclasses .Mean san dstandar ddeviation s (inbrackets )ar eprovided , exceptfo rbod ymoul tan dsumme rplumag escor ewher eth emedia nvalu ean d therang e(i nbrackets )ar epresented .Dat afo r198 5an d 1986ar e combined.

~~~~~~Juvenile Ageuncertai n Adult (n-113) (n=13) (n=287)~~~~~~

Wing length (mm) 150.9 (4.4) 156.1 (5.2) 157.6 (5.0) Billlengt h(mm ) 23.2 (0.9) 23.5 (1.5) 23.4 (2.0) Totalhea d length(mm ) 51.2 (1.1) 51.5 (1.0) 51.4 (2.0) Tarsus+ to e(mm ) 52.5 (1.6) 52.9 (1.5) 52.8 (1.9) Bodyweigh t (g) 89.3 (7.0) 96.5 (9.0) 109.4(14.5 ) Bodymoul t 0 (0-3) 0 (0-2) 1 (0-3) Summerplumag e 1.5 (1-3) 2 (1-5) 4 (1-7)

~~~~~~327 % MOULTING "*O0~~~~~~

~~~~~~• AD IS45~~~~~~

~~~~~~• AD. Ifttó~~~~~~

~~~~~~D Jov. 1905~~~~~~

~~~~~~O JUM. »86~~~~~~

~~~~~~FEBR. MABCW APRtL-~~~~~~

Figure 14.1. a_.Proportio n of adult and juvenile Turnstones caught showing body moult for five different periods in 1985an d 1986.b . Proportion of adult and juvenile Turnstones caught insumme r plumage (i.e. summer plumage three quarters ormore )fo r five different periods in 1985an d 1986). relationshipwa sobtaine d betweenweigh tlos s (dw)an d timela g(dt) : In(dw )= 0.33 9I n(dt )+ 0.330 ,r 2=0.41,p<0.001 ,n=20 . Weight losswa sno tcorrecte d forthough ,sinc emos tbird swer eweighe d within 1t o5 hour safte r capture,whic hwoul dlea d toa maxima l difference inth ecorrectio n termbetwee nindividual so fonl y 1g .

~~~~~~14.2 Moultingan dgainin gweigh t AdultTurnstone s startedmoultin g tosumme rplumag ei nth efirs tweek so f March (Fig. 14.1).A t theen do fApri lmos tadult sha dacquire d three~~~~~~

~~~~~~BODY MOtilX AOUCT jaV£kllL_E 3 5 6 7 7 1 1 2~~~~~~

~~~~~~2 3 9 12 15 17 3~~~~~~

~~~~~~-1 6 14 16 9 22 15 13 6 1~~~~~~

~~~~~~O 32 9 6 4 18 36 8 65 17 4 2 â 5 6 9 2 3 a S 6 •?• SUMME«. PCUMAOE'~~~~~~

~~~~~~Figure 14.2. Body moult in relation to theexten t of summer plumage for a. adult and b. juvenile Turnstones (data of 1985an d 1986 combined).~~~~~~

~~~~~~328 BODV WEKiMT. a,~~~~~~

~~~~~~4JO-~~~~~~

~~~~~~A20-~~~~~~

~~~~~~•12 3 4 5 6 -«-WINTER .SUMMER EXTENT OF SUMME« PLUMAGE~~~~~~

~~~~~~Figure 14.3. Bodyweigh to fadult si nrelatio nt oth eexten to fsumme r plumage,separate d fordifferen t bodymoul tscore s(dat ao f198 5an d198 6 combined).~~~~~~

~~~~~~BODV WE.IG.MT, ~~. I98S KI6L.D • AD lasé 15D D juj. «es~~~~~~~~

~~~~~~(J JU/ q66 12S-~~~~~~

~~~~~~1O0~~~~~~

~~~~~~?S FEBR. MA.RCH APRW- MAV~~~~~~

Figure 14.A. Average weight of adult and juvenile Turnstones caught in five different periods in 1985 and 1986. Bars represent 95% confidence limits. For comparison average weights of adults in South Africa (Summers & Waltner 1979). Morecambe Bay (Clapham 19"9) and the Wadden Sea (Engelmoer in prep.) are also presented.

329 quarters or more of their summer plumage and fewwer e still actively moulting. Surprisingly, several non-moulting adults had progressed only halfway towards completion (Fig. 14.2). Non-moulting individuals were heavier thanmoultin g individuals when they had attained one quarter summer plumage or more (Fig. 14.3). This suggests that at least some adults temporarily suspended moulting tomigrat e from the Banc d'Arguin. They were caught in the first and last weeks ofApril . Contrary to adults,onl y aminorit y of juveniles was caught moulting (Fig. 14.1)an d no juvenile had progressed beyond one quarter summer

~~~~~~WEHOMT DIFFERENCE, Q 40~~~~~~

~~~~~~-10~~~~~~

~~~~~~• EXRLV 1385 , LATE IM VMt -30 • EAACV lôfié , LA.TE. IM 138$ D wtrwiM »~~~~~~

Figure 14.5. Weight difference (in g) inrelatio n to the interval (days)betwee n first and second capture. Each dot represents one individual (only adults). Open dots and squares refer to birds recaptured within the same year: dw = 13.55 In (dt + 1)- 44.61 ,r 2=0.19,p=0.06 , n=14 , where dw is weight difference in grar:an d dt is interval in days. Closed dots and squares refer tobird s caught in both 1985an d 1986:d w= 12.85 In (dt + 1)- 23.26, r2=0.57,p^O.001 ,n=16 .

330 plumage (Fig. 14.2). Inadditio n theweigh to f juveniles showedn o tendency toincreas e intim e (Fig. 14.4). Inever yperio d theweight so f juvenilesan dadult swer ehighe ri n 1985tha ni n198 6(Fig . 14.4). Several lineso fevidenc e indicate thatdepartur ecommence sa t theen d ofApril .Th epatter no fth eaverag eweigh tgai ndepicte d infigur e14. 4 maywel lcorrespon d toth epatter n forindividual su pt otha tperiod . Surprisinglyonl y 5ou to f 14adult srecapture d within thesam eyea r showeda positiv eweigh t change (Fig. 14.5). Iti spossibl e thatdu et o theextrem eenvironmenta lcondition s theeffect so fcatchin gan dhandlin g birdsar emor edetrimenta l thanthe yappea r tob ei ntemperat ezone s (Davidson 1984).Larg eweigh tdecrease swer eassociate d withshor ttim e intervals,suggestin g thatth ebird sneede d sometim et orecove rfro mth e negativeeffect s ofbein gcaugh t (Fig. 14.5). Assuming thatindividual sfollo wmor eo rles sth esam emigratio n programfro mon eyea r toth enex t (Metcalfe& Furnes s 1985),w eca n meaningfullyanalys e theweigh t differenceso findividual scaugh ti n different years.I fth edifferenc e inweigh tgai nbetwee n 1985an d 1986 isreal ,w eexpec t thatbird scaugh tearl yi n198 6an dlat ei n198 5sho w largerweigh tgain s thanbird scaugh tearl yi n198 5an dlat e in1986 . Thisma yb etrue ,bu tther ei sto omuc hscatte ri nth edat at omak eth e differences significant (Fig. 14.5).B ylumpin g thedat aw ehop etha t under-an doverestimate sar ecancelle d out.Th efac t thatweight s 'gained'betwee nyear swer emuc hlarge rtha nweight sgaine dwithi na yea r isadditiona levidenc eo fa negativ eeffec to fhandling .Th efac ttha t thecurv elevel sof fa tlon ginterval sma yb ecause d bylon ginterval s beingdu et obird scaugh ti nFebruary .Fig .14. 4show stha tweight sstar t toincreas efro mMarc honwards .Th erat eo fweigh tgai nca nb e meaningfully calculated onlywhe n thetim einterva li ssufficientl ylong , sointerval so fles stha na wee kwer erejected . Table 14.2suggest stha tbird sgaine dweigh ta ta faste rrat ea tth e endo fApril ,bu ti ti sno tsignificant .Eve nso ,th ecalculate d average rateo f0.9 1g/da yfo rindividua lbird si smuc hhighe rtha nth eaverag e rateo f0. 5 forth epopulatio n (Fig. 14.4).Thi sindicate s thatsom e heavyindividual sdeparted ,thereb ydepressin g theweigh tgai no fth e population.Th esam econclusio nfollow sfro mfigur e 14.6:th eweigh t distributiono f theindividual s 'readyt ogo ' (nobod ymoul tan dthre e quarters summerplumag e ormore )di dno tchang e from themiddl eo fApri l towards theen do fApril .

~~~~~~3U 14.3 Discussion The rate of weight gain of adults departing from the Banc d'Arguin is low compared to adults departing from South Africa or from Europe (Fig. 14.4,~~~~~~

Table 14.2. Rate of 'weight gain' (g/day) for birds caught in a period in 1985 different from their capture period in 1986 (i.e. an interval of more than 7 days). Birds are grouped according to the latest capture date. A one-way analysis of variance showed the groups to be not significantly different (p-0.13).

~~~~~~Date of 2nd capture Mean weight gain (g/day) S.D. (n)~~~~~~

~~~~~~26 March- 6 April 0.51 0.05 3 7 April-20 April 0.63 0.28 4 21 April-28 April 1.47 0.97 4~~~~~~

~~~~~~Ungrouped data 0.71 0.22 11~~~~~~

Table 14.2). Thechang e inth e population mean probably misrepresents the pattern forth eindividua l duet oheav y individuals 'continuously' leaving tomigrat e and light individuals arriving after migration.Th e first problem applies toal ldat a sets. Thesecon d problem applies to Europe and perhaps toth eBan c d'Arguin. Indeed the rate of weight gain estimated from between-year recaptures was twice thevalu e estimated from changes inth epopulatio n mean. However, even at this rate it would take the birds weighing 120g at theen do f April more than a month to reach weights of 160g or more as observed in South Africa and Europe. Could itb e that thelo wweight s measured on theBan c d'Arguin aredu e to ourcatchin g method biasing towards hungry birds in poor conditions?

~~~~Table 14.3. Average weight (sample size in brackets)fo r Turnstones caught with different catching devices.Dat a refer to 1985 only, since nearly all birds were caught with clap nets in 1986.~~~~

~~~~~~Age class Period Mist nets Clap nets Cannon nets Results ANOVA~~~~~~

~~~~~~Juveniles 7-20 Apr 95.0 ( 5) 99.5 ( 2) 93.3 (4 ) p=0.623 Adults 25Mar- 6 Apr 111.6 ( 5) 107.3 (56) p=0.406 Adults 7-20 Apr 107.1 (15) 118.0 (6 ) 125.5 (13) p=0.001~~~~~~

332 Table 14.3 shows that there is only one period in which the catching method had a significant effect on body weight.However , this isdu e to mist net birds being extremely light. Birds caught with the clap net did

~~~~~~KUJMBER OFQK2JDS — 20 13-2 /24-S •25-3/6-^~~~~~~

~~~~~~SO - 10 -JÊM is s *o - 0 f NlllHIIMOlini 15 XS-3 l6-t\~~~~~~

~~~~~~10 10~~~~~~

~~~~~~ÏÏIÏÏÏÏI O 0~~~~~~

~~~~~~1S " ?-4/2o-A~~~~~~

~~~~~~•to lo~~~~~~

~~~~~~go10 O-H O 120H O -MO~~~~~~

~~~~~~2i-M/2^-*t WINTER tt_UM*GE 15~~~~~~

~~~~~~MOULTING~~~~~~

~~~~~~StASPEHOED MOULT 5~~~~~~

~~~~~~SOMME« PLXJMA«E 0 ill 90 100 HO 120 13omoIS O 160 BOOY VvJEVGWT , G~~~~~~

Figure 14.6. Frequency distribution of weights of adult Turnstones in four different periods in 1985an d 1986.Difference s inhatchin g indicate: birds in winter plumage (plumage score 1o r 2),showin g no body moult, all birds showing body moult,bird s in suramerplumag e (score 5,6 or 7)showin g no body moult. not differ much from birds caught with the cannon net.Ver y few birds were caught in mist nets outside the middle ofApri l 1985. Excluding the mist net samples from the analysis would virtually eliminate the positive weight change from the middle of April towards the end of April 1985. Inal l it seems safe toconclud e that the birds leaving in early April did sowit h low body weights of around 130g .A crude estimate yields a maximum flight distance of 2000k m (Davidson 1984), indicating Morrocco as thenex t stopover site.

~~~~~~334 APPENDIX XX~~~~~~

~~~~~~Cap H lune~~~~~~

~~~~~~Agadir \~~~~~~

~~~~~~ILE D'ARCUIN \~~~~~~

~~~~~~HA \C D'ARi.ll\~~~~~~

~~~~~~Tanoudert /~~~~~~

~~~~~~Ebi'lk Aitnav~~~~~~

~~~~~~liaic d'Auuotif\s\~~~~~~

~~~~~~N,ROUMI ^ ^^RA X •~~~~~~

~~~~~~Cop I imiris f~-\-^'^Z . • >*^^ Aougu » Namghar~~~~~~

~~~~~~0 10 20 30 40 km~~~~~~

~~~~~~5 10 km WlWO-reportsavailable :~~~~~~

Altenburg,W.,M.Engelmoer ,R.Me s& T.Piersm a 1982.Winterin gwader so n theBan cd'Arguin-Mauritania .Repor to fth eNetherland s Ornithological MauritanianExpeditio n1980 .Communicatio nNo .6 Wadde nSe aWorkin g Group,Stichtin gVet hto tSteu naa nWaddenonderzoek ,Texel .28 4pp . (WlWO-report1 )Sol dout . Altenburg,W.1987 .Waterfow l inWes tAfrica ncoasta lwetlands :a summar y ofcurren tknowledge .WlWO-repor t 15,Zeist ,Th eNetherlands .Df1 . 10,-. Bennet,CA.,R.G.Bijlsm a& R.Stouthame r1982 .Surve yo fwaterbird so n Egyptianwetlands ,autum n1981 .WlWO-repor t 16,Zeist ,Th e Netherlands.Dfl .7,50 . Berg,A.B.vande n1988 .Morocca nSlender-bille dCurle wsurvey ,winte r 1987-88.Join trepor to fWIW Oan dICB Pnr .29 ,Zeist ,Th eNetherland s andCambridge ,England .Dfl .15,- . Berk,V.vanden ,R.G.Bijlsm a& F.E.d eRode r1985 .Th eimportanc eo fsom e wetlands inTurke yfo rtransien tan dwinterin gbird s inTurkey . WlWO-report 6,Zeist ,Th eNetherlands .Dfl .10,- . Berk,V.vanden ,D.va nDorp ,O.va nHoor n& R.Vo s 1986.Crane san d waterfowlcount so fsom eTurkis hwetlands .WlWO-repor t 10,Zeist ,Th e Netherlands.Dfl .12,50 . Berk,V.vanden ,J.P.Cronau ,T.M.va n derHav e& J.P.W.Letscher t(eds. ) 1988.Wader san dwaterfow l inth eGukurov aDelta ,Souther nTurkey . spring1987 .WlWO-repor t 22,Zeist ,Th eNetherlands .Pric eno tye t known. Bijlsma.R.G.& F.E.d eRode r1985 .Wader salon gth ecoas to fThailan d duringNovembe r andDecembe r 1984.WlWO-repor t4 ,Zeist ,Th e Netherlands.Dfl .10,- . Bijlsma.R.G.& F.E.d eRode r1986 .Note so nth ebird so fsom ewetland si n Turkey.WlWO-repor t 12,Zeist ,Th eNetherlands .Sol dout . Chalabi.B.,J.Harriso n &G.va nDij k1985 .Le szone shumide sd uNord-Es t Algeriene n1984 .WlWO-repor t 8,Zeist ,Th eNetherlands .Dfl .10,- . Chalabi.B.& G.va nDij k1988 .Le szone shumide sdan sl aregio nd eAnab a etE lKal ae nMa i1987 .WlWO-repor t 24,Zeist ,Th eNetherlands .Dfl . 7,50. Dijk,A.J.van,K.va nDijk ,L.Dijksen ,T.va nSpanj e& E.Wymeng a1986 . Winteringwader san dwaterfow l inth eGul fo fGabes ,Tunisia , January-March 1984.WlWO-repor t 11,Zeist , The Netherlands. Df1.30,- . Dijksen.L.J. & F.J.Koning 1986.Mid-winte r waterfowl census,Turke y 1986. WlWO-report 13,Zeist , The Netherlands. Df1.10,- . Dijksen.L.J. & P.vande r Wolf 1987.Mid-winte r waterfowl census Turkey January 1987.WlWO-repor t 18,Zeist , The Netherlands. Dfl. 7,50. Dijksen,L.J. &A-M.Chr.Blomer t 1988.Mid-winte r waterfowl census Turkey January 1988.WlWO-repor t 21,Zeist ,Th e Netherlands. Dfl. 7,50. Ens,B. 1985. Tussen Sahara en Siberië.WlWO-repor t 9-N, Ewijk, The Netherlands. Dfl. 7,50. Ens,B. 1985. Entre Sahara et Siberië.WlWO-repor t 9-F, Ewijk, The Netherlands. Dfl. 5,-. Ens.B.J., T.Piersma,W.J.Wolff , L.Zwarts (eds.) 1989.Repor t of the Dutch-Mauritanianprojec t Banc d'Arguin 85/86. Joint report ofWIW O andRI N nr. 25,Zeist ,Th e Netherlands. Dfl.35,- . Kersten,M., T.Piersma, C.Smit & P.Zegers 1983.Wade r migration along the Atlantic coast ofMorocco ,Marc h 1981.WlWO-repor t 2,Texel ,Th e Netherlands. Dfl. 25,-. Lensink,R. 1987.Note s on thebird s of somewetland s inNorth-Eas t Greece and Turkey. WlWO-report 19,Zeist ,Th e Netherlands. Dfl. 7,50. Marteijn,E.C.L. & P.L.Meininger (eds.) inprep .Waterbird s in Nort-East Greece spring 1987.WlWO-repor t 20,Zeist ,Th e Netherlands. Price not yet known. Philippona,J. 1985.Waterbird s at somewetland s inTurke y andGreece . WlWO-report 3, Zeist,Th e Netherlands. Dfl.4,- . Piersma.T. 1985.Wade r studies andwaterbird s in the Nakdong Estuary, South Korea, in September 1984.WlWO-repor t 7, Zeist,Th eNetherlands . Dfl. 12,50. Roder,F.E.de 1985.Waterbird s on some Turkish wetlands, October/November 1983. WlWO-report 5, Zeist,Th e Netherlands. Dfl. 8,-. Schekkerman.H. &J.C.J.va nWette n 1987.A n ornithological winter survey of Lake Turkana, Kenya.WlWO-repor t 17,Zeist ,Th e Netherlands.Dfl . 7,50.

Reports canb e ordered by paying toposta l giro account 2.666.009 or to ABN bank account 57.02.16.613 of Stichting WIWO, Ewijk, The Netherlands. Postage is included in theprice . Devolgend eRIN-rapporte nkunne nbestel dworde ndoo roverschrijvin gva nhe t verschuldigdebedra go pgir o51 60 64 8va nhe tRI Nt eLeersu monde rvermeldin g vanhe trapportnummer .U wgiro-overschrijvin g geldtal sbestelformulier ; toezending geschiedtfranco .Gebrui kgee nverzamelgir o omdathe tadre sva nd e bestellernie to ponz egiro-bijschrijvin gword tvermel dzoda the tbesteld enie t kanworde ntoegezonden .

86/7 M.Nooren,Inventarisati eva nd ehoutwalle n inhe tnational epar kd e HogeVeluwe .4 9p . f8,- 86/8 M.Nooren,Ove rhe tverlede nva nd eHog eVeluwe .8 9p .f 13,5 0 86/9 K.Stoker,D everspreidin gva nd erod ebosmiere no pd eHog eVeluwe . 110p .f 15,6 0 86/19B.va nNoorden ,Dynamie ke ndichthei dva nbosvogel se ngeïsoleerd e loofbosfragmenten.5 8p .f 8,5 0 86/21G.P.Gonggrij p (red.),Gea-objecte nva nLimburg .28 7p .f 34, - 87/1 W.O.vande rKnaa p& H.F.va nDobben ,Veranderinge n ind eepifytenflor ava n Rijnmondsind s1972 .3 6p . f6,- 87/2 A.vanWinde ne tal. ,Ruimtelijk erelatie svi avogel si nhe tStrijper-Aa - gebiedgedurend ebroedtij de nzomer .9 7p .f 14,5 0 87/3 F.J.J.Niewold,D ekorhoender sva nonz eheideterreinen :verleden , hedene ntoekomst .3 2p . f5,- 87/4 H.Koop,He tRIN-bosecologisc hinformatiesysteem ; achtergrondene n methoden.4 7p .f 7,5 0 87/5 K.Kersting,Zuurstofhuishoudin gva ntwe epolderslote ni nd epolde r Demmerik.6 3p .f 11, - 87/6 G.F.Willemsen,Bijzonder eplantesoorte ni nhe tnational epar kd e HogeVeluwe ;voorkome ne nveranderingen .9 2p .f 13,5 0 87/7 M.J.Nooren,He tverlede nva nd ehoutwalle n inhe tnational epar k deHog eVeluwe .2 3p . f5,- 87/8 G.GrootBruinderink ,D.Kloe g& J.Wolkers ,He tbehee rva nd ewild e zwijneni nhe tMeinweggebie d (Limburg).9 6p .f 14,5 0 87/9 K.S.Dijkema,Selectio no fsalt-mars hsite sfo rth eEuropea nnetwor ko f biogenetic reserves.3 0p .f 5,5 0 87/11G.J.Baaijens ,Effecte nva nontwateringswerke n ind eruilverkavelin g Ruinerwold-Koekange.6 4p . f9,- 87/13J.Weinreic h& J.Oud eVoshaar ,Populatieontwikkelin gva noverwinterend e vleermuizeni nd emergelgroeve nva nZuid-Lintbur g (1943-1987).6 2p . f8,- 87/14N.Dankers ,K.S.Dijkema ,G.Lond o &P.A.Slim ,D eecologisch eeffecte nva n bodemdalingo pAmeland .9 0p .f 13,5 0 87/15F.Fahne r &J.Wiertz ,Handleidin gbi jhe tWAFLO-model .9 9p .f 14,5 0 87/16J.Wiertz ,Modelvormin gbi jd eprojecte nva nWAFL Oe nSWNBL .3 4p . f6,- 87/17W.H.Diemon t& J.T.d eSmid t (eds.),Heathlan dmanagemen t inTh eNether lands.11 0p .f 15,5 0 87/18Effecte nva nd ekokkelvisseri j ind eWaddenzee .2 3p .f 3.7 5 87/19H.va nDam ,Monitorin go fchemistry ,macrophytes ,an ddiatom si n acidifyingmoorlan dpools .11 3p .f 16, - 87/20R.Torenbeek ,P.F.M.Verdonscho t &L.W.G.Higler ,Biologisch e gevolgenva n vergrotingva nwaterinlaa t ind eprovinci eDrenthe .17 8p .f 23, - 87/21J.E.Winkelma n& L.M.J.va n denBergh ,Voorkome nva neenden ,ganze ne n zwanennabi jUr k (NOP)i njanuari-apri l1987 .5 2p .f 7,5 0 87/22B.va nDessel ,T everwachte necologisch eeffecte nva npekellozin g inhe t Eems-Dollardgebied.7 1p .f 10, - 87/23W.D.Dennema n& R.Torenbeek ,Nitraatemissi e enNederlands eecosystemen : eenglobal erisico-analyse .16 4p .f 21, - 87/24M.Buil ,Begrazin gva nheidevegetatie s dooredelher te nmoeflon ;ee n HogeVeluwe .4 9p .f 7,5 0 87/26H.A.T.M.va nWezel ,Heidefaun a inhe tnational e parkd eHog eVeluwe . 54p .f 8, - 87/28G.M.Dirkse ,D enatuu rva nhe tNederlands e bos.21 7p .f 27,5 0 87/29H.Siepe l etal. ,Behee rva ngraslande n inrelati e totd eongewerveld e fauna:ontwikkelin g vanee nmonitorsysteem . 127p .f 17.9 5 88/30P.F.M.Verdonscho t& R.Torenbeek ,Lettercoderin g vand eNederlands e aquatischemacrofaun a voormathematisch e verwerking.7 5p .f 10, - 88/31P.F.M.Verdonschot , G.Schmidt,P.H.J.va nLeeuwe n& J.A.Schot ,Steek - muggen (Culicidae)i nd eEngbertsdijkvenen .10 9p .f 15,5 0 88/33H.Eijsackers ,C.F.va nd eBund ,P.Doelma n& Wei-chu nMa ,Fluctuerend e aantallene nactiviteite nva nbodemorganismen .8 5p .f 13, - 88/34Tok ed eWit ,D eeffecte nva nozo no pnatuurlijk e ecosystemen;ee n literatuuronderzoek.2 7p .f 5,2 0 88/35A.J.d eBakke r& H.F.va nDobben ,Effecte nva nammoniakemissi eo pepify - tischekorstmossen ;ee ncorrelatie f onderzoek ind ePeel .4 8p .f 7,5 0 88/36B.v.Dessel ,Ecologisch e inventarisatie vanhe tIJsselmeer .8 2p .f 12,7 5 88/37A.Schotman ,Tusse nbo se nhoutwal ;broedvogel s inee nTwent scultuur landschap.8 7p .f 13,2 5 88/38P.Opda m& H.va nde nBijtel ,Vogelgemeenschappe nva nhe tlandgoe d Noordhout.6 6p .f 10, - 88/39P.Doelman ,H.Loone n &A.Vos ,Ecotoxicologisc honderzoe k inme tEndosulfa n verontreinigde grond:toxicitei t ensanering .3 4p .f 6, - 88/40G.P.Gonggrijp ,Voorste lvoo rd eafwerkin g vand egroev eBelveder eal s archeologisch-geologisch element.1 3p .f 3, - 88/41J.L.Mulde r (red.), Devo si nhe tNoordholland sDuinreservaat .Dee l1 : Organisatie ensamenvatting .3 2p . 88/42J.L.Mulder ,idem .Dee l2 :He tvoedse lva nd evos .7 8p . 88/43J.L.Mulder ,idem .Dee l3 :D evossenpopulatie .12 9p . 88/44J.L.Mulder ,idem .Dee l4 :D efazantenpopulatie .5 9p . 88/45J.L.Mulde r &A.H.Swaan ,idem .Dee l5 :D ewulpenpopulatie .7 6p . Derapporte n41-4 5worde nnie t losverkoch tmaa ral sseri eva nvij fvoo r f25 .

88/46J.E.Winkelman ,Methodologisch easpecte nvogelonderzoe k SEP-proefwind- centraleOosterbieru m (Fr.).Dee l1 .14 5p .f 20, - 88/47T.A.Renssen ,D eherintroducti e vand eraa f (Coraxcorax )i nNederland : eenoverzicht .3 0p .f 5,5 0 88/48J.J.Smit ,He tEemlan d end epolde rArkemhee nron dhe tbegi nva nd e twintigsteeeuw .6 4p .f 9, - 88/49G.W.Gerritsen ,M.de nBoe r& F.J.J.Niewold ,Voedselecologi eva nd evo si n Nederland.9 6p .f 14,2 5 88/50G.P.Gonggrijp ,Permanent egeologisch eontsluitinge ni nd etalud sva n RijkswegA 1bi jOldenzaal .1 8p .f 3,5 0 88/51P.Spaak ,Ee nmodelmatig ebenaderin g vand eeffecte nva ngraslandbehee ro p hetpopulatieverloo p vanweidevogels .4 2p .f 7.5 0 88/53L.W.G.Higle r &F.F.Repko ,Analys eva nd emacrofaun ava nd eHierdens e Beek.9 7p .f 14,2 5 88/54H.W.d eNi e& A.E.Jansen ,D eachteruitgan g vand eoevervegetati e vanhe t Tjeukemeertusse nOosterze e (Buren)e nEchten .1 8p .f 4,5 0 88/55R.Torenbeek ,Hydrobiologi e enwaterhuishouding :ee nbeleidsvoorbereidend e studie.14 8p .f 20,5 0 88/56P.A.J.Frigg e &CM.va nKessel ,Adde re nzandhagedi so pd eHog eVeluwe : biotopene nbeheer .1 6p .f 3,5 0 88/57A.J.d eBakker ,Monitorin g vanepifytisch ekorstmosse n inNederlan di n 1987. 35p .f 6, - 88/59F.J.J.Niewol d5 eH.Nijland ,D eSallands eHeuvelru g alsreservaa tvoo rhe t Westeuropese heidekorhoen.10 2p .f 14,5 0 88/63S.E.va nWiere n& J.J.Borgesius ,Evaluati eva nbosbegrazingsobjecte n in Nederland.13 3p .f 19, - 88/64G.P.Gonggrij p (red.),Gea-objecte nva nGelderland .34 2p .f 40, - 88/68R.Noordhuis ,Maatregele n tervoorkomin g enbeperkin gva nschad edoo r zilvermeeuwen.4 8p .f 7,5 0

~~~~~~89/6B.J.Ens ,T.Piersma ,W.J.Wolf f &L.Zwart s1989 .Repor to fth e Dutch-MauritanianProjec t Bancd'Argui n1985-1986 .WlWO-rappor t25 .f 35, - Ecologie van kleine landschapselementen~~~~~~

Kleine landschapselementen vormen voor veel soorten planten en dierenva n het cultuurlandschap biotoop en ecologische infrastructuur. In 1986 wijdde het RIN een studiedag aan dit thema. Inhe t verslaghierva n werd een overzicht gegevenva n de stand vanhe t onderzoek en er is ruime aandacht besteed aan praktijkproblemen van de landinrichting.

~~~~~~88pagina's , geïllustreerd prijs ƒ20, - bestelcode: KLE~~~~~~

~~~~~~Ecologie van kleine landschapselementen~~~~~~

~~~~~~RsikMîiMtUitti voor N;iU!urtx."iK'e!'~~~~~~

~~~~~~Biologische waterbeoordeling: instrument voor waterbeheer?~~~~~~

~~~~~~DeWerkgroe p Biologische Waterbeoorde ling organiseerde in 1987 in samenwer king met het RIN een symposium waarvan debijdrage n gebundeld zijn in ditboek .~~~~~~

~~~~"Dewerkgroe p heeft een rijk enplezie rig geïllustreerd kader uitputtend op poten gezet. Latenw e voortaan spreken van deblauw e gids enwi e hem onverhoopt nog niet heeft: aanschaffen!"~~~~

~~~~~~Jaap Dorgelo inHydrobiologica l Bulletin 22,2: 209.~~~~~~

~~~~~~184 pagina's prijs ƒ 35,- bestelcode: BW~~~~~~

Beide boeken zijn tebestelle n door overschrijving vanhe t verschuldigde bedrag op giro 516 06 48va nhe t RIN te Leersum onder vermelding van de bestelcode. Uw giro-overschrijving geldt alsbestelformulier ; toezending geschiedt franco.