Migrant and Resident Waders in the Cape Verde Islands

Home , Green sandpiper

(range62.9%-82.4%), with that of maleslarger (64.9%- seasonsfrom 1.6 to 2.6, on average2.0 of the hatched,and 83.0%,average 78.2%) than females (57.2%-86.3%, average on average1.1 (0.9-1.2)of fledgedbirds per nesting pair. 67.5%). Mostnesting birds (over 60.0%) are of localorigin, malesconsiderably predominate over females (among CONCLUSIONS individualsof oneto sevenyears in age- by 1.6 times).The numberof immigratingfemales is muchgreater than that of Largelocal colonies of Redshanksin the southof the Ukraine males.The reproductive nucleus comprises birds of two to are, inthis way, essentially autonomous. They are character- fiveyears in age. Whena colonyis declining, the role of birds izedby mechanismsregulating their numbers and colony of localorigin increases, while with an expandingpopulation, structuresboth at the levelof nestlingsand at an olderage. this role decreases. The mechanismswhich regulate population size are productivity,adult and nestling survival, and the degreeof natal In differentyears, the numberof hatchednestlings in the local philoparryshown by nesting birds. Malesrepresent a more colonywas more stable (the maximum difference was 28.5%) conservativegroup in such colonies, which is mainlyrespon- thannumbersof nestingbirds (the maximumdifference was siblefor the isolationof colonies,and, most likely, for their 32.5%).The number of fledgingbirds is stillmore stable; the geneticand phenotypical peculiarity. The lessphilopatric nestlingmortality varying from 36.3% to 69.6%,on average femalespromote stabilization of characterswithin wider 52.1%. Overallaverage productivity fluctuates in different territorial limits.

Migrantand residentwaders in the Cape Verde Islands

C.J. Hazevoet

Hazevoet,C.J. 1992. Migrantand resident waders in the Cape Verde Islands. Wader Study Group Bull., 64:46 - 50

C.J.Hazevoet, Institute of TaxonomicZoology, University of Amsterdam, P.O. Box4766, 1009A T Amsterdam, The Netherlands.

INTRODUCTION observationsup to the mid-1960s,and were first to comment on fluctuationsof wadernumbers as observedduring their During1986-90, I visitedthe CapeVerde Islands (officially the stayon S•.oVicente between January-March 1966. Frade RepSblicade CaboVerde) in connectionwith the National (1976)reported on birdscollected by Jaime Vieira dos Santos Parksand ProtectedAreas Program, developed under the in 1969,1970 and 1972,while annotated lists of species auspicesof theInternational Council for BirdPreservation observedduring short visits were published by Lambert (NetherlandsSection) and the InstitutoNacional de (1980),Nerrevang & Hartog(1984), Summers-Smith (1984) Investiga½oAgr•ria (Cabo Verde). Prior to threeprolonged andHartog (1990). Furthermore, much unpublished data from staysin 1988-90,I was in the islandson two fortnight visits as variousobservers who have visited the islandsduring the last a tour-leaderfor groups of naturalistsin 1986-88.Altogether, I decadewere collected while preparing a forthcomingCheckl- spenteight months in the islands,covering all monthsexcept istof theBirds of theCape Verde Islands (Hazevoet in prep.). Julyand mostof August.As partof a generalcollection of I herereport on myobservations ofwaders during 1986-90. ornithologicaldata throughout the archipelagoduring all visits, counts of waders were made at a few selected sites. THE ENVIRONMENT

Littlehas been published on migrantwaders in the Cape TheCape Verde Islands are situatedin the easternAtlantic, VerdeIslands. Bannerman & Bannerman(1968) summarized 500-600km west of S•n6gal.There are nineinhabited main

46 Table1. Waderscounted at thePedra Lume salt-pans, Sal. 1 23øW 30Aug 30 Oct 23 Dec 28 Apr 1988 1988 1987 1990

Black-wingedStilt H. himantopus 75 75 75 75 RingedPlover C. hiaticula 1 2 5 10 KentishPlover C. alexandrinus 25 25 50 25 GreyPlover P. squatarola 1 3 3 LapwingV. vanellus - 2 SanderlingC. alba 40 40 150 50 LittleStint C. minuta 5 2 10 10 CurlewSandpiper C. ferruginea 12 16 100 25 RuffP. pugnax 2 - - Black-tailedGodwit L. limosa 2 2 Bar-tailedGodwit L. lapponica 2 WhimbrelN. phaeopus 2 - Redshank T. totanus 2 2 4 1 Greenshank T. nebularia 4 4 6 1 CommonSandpiper A. hypoleucos 1 - TurnstoneA. interpres 100 100 75 20

islands and several smaller uninhabited islands and islets (Figure1 ). Figure1. Mapof the Cape Verde Islands. 1. PedraLume salt-pans; 2. Santa Mariasalt-pans; 3. Rabil Lagoon; 4. PortoFerreira Lagoon; 5. PedraBadejo Lagoon;6. Baiades Gatas, The three easternmostislands - Sal, Boavistaand Maio - are ratherflat and have considerable stretches of sandybeach as Table2. Waderscounted at theMindelo sewage-farm, S•io Vicente. wellas salt-pansand lagoons. The island of Santiagois mountainousand has mainly rocky shores but there are some 27 Mar 14 Jun 1990 1989 sandybeaches and a largelagoon. S•.o Vicente has mainly rockyshores but there are sandybeaches, reefs and a RingedPlover C. hiaticula 10 - KentishPlover C. alexandrinus 15 50 lagoon,and alsoa sewage-farmwhere waders can be found Uttle Stint C. minuta 1 - innumbers. The uninhabited island of SantaLuzia has rocky SanderlingC. alba 30 - shoreswith some sandy beaches, but was visited by meonly Greenshank T. nebularia 25 4 once for a few hours when few waders were observed. WoodSandpiper T. glareola 3 CommonSandpiper A. hypoleucos 3 - WhimbrelN. phaeopus 3 8 The islandsof Fogo,Brava, Santo Ant•.o and Sao Nicolauare TumstoneA. interpres 50 3 highlymountainous and generally have steep rocky coasts withoutlagoons and only small stretches of sandybeach, and Table 3.Waderscounted at Baia das Gatas, S•o Vicente. thereforesupport only few waders.The uninhabitedislets of 6 Oct 26 Mar Rombos,Branco and Raso are rocky,with small sandy 1988 1990 beacheson Cima (Rombos) and Branco, and few waders RingedPlover C. hiaticula 2 1 were found here. Kentish Plover C. alexandrinus 2 2 GreyPlover P. squatarola 3 1 BREEDING RESIDENTS WhimbrelN. phaeopus 2 1 Greenshank T. nebularia 1 - TurnstoneA. interpres 10 8 Threewader species breed in the Cape Verde Islands: Cream-colouredCourser Cursorius cursor, Black-winged Stilt Himantopushimantopus, and KentishPlover Charadrius TheBlack-winged Stilt only breeds in the salt-pans at Pedra alexandrinus. Lumeon the islandof Sal.The breeding population is c. 30 pairs.Naurois & Bonnaffoux(1969) suggested that these are Thedesert-dwelling Cream-coloured Courser is a widespread regularlyaugmented by migrantsfrom abroad. However, andrather common resident on Sal, Boavista, Maio, Santiago numberscounted in four different months (Table 1 ), suggest andSao Vicente, which has also been recorded (but not that the birds are resident and there is no indicationof provedbreeding) on SantoAntao, Santa Luzia, Raso and Sao migrantsvisiting the island. Occasionally, a few (1-5) stilts are Nicolau(Hazevoet in prep.).It is notfurther considered here. seenat lagoonson Boavista,Maio and Santiago, as wellas in

47 Table4. Waderscounted at RabilLagoon, Boavista. in numbersas shownin Tables1 and2 wereprobably due to 18 Sep 14 Nov 19 Mar 22 May 1988 1988 1990 1989 localmovements of roostingbirds.

Black-wingedStilt H. himantopus 3 NON-BREEDING VISITORS RingedPlover C. hiaticula 5 10 10 3 Kentish Plove C. alexandrinus 20 25 25 25 GreyPlover P. squatarola 1 10 1 In contrastto thesituation along the coastsof theWest SanderlingC. alba 14 15 50 20 Uttle Stint C. minuta 1 Africanmainland, numbers of winteringwaders in the Cape CurlewSandpiper C. ferruginea 8 12 Verde Islands are small. Bar-tailedGodwit L. lappon/ca 2 2 WhimbrelN. phaeopus 24 4 4 Redshank T. totanus 2 Thethree eastern islands (Sal, Boavista, Maio) support the Greenshank T. nebularia 3 1 highestnumbers of migrantwaders to befound in the CommonSandpiper A. hypoleucos 2 1 archipelago,as theyhave the mostsuitable habitats, and TurnstoneA. interpres 55 + 60 30 perhapsalso because they are nearestto the Africanmain- land.Here, and on Santiago,S•.o Vicente and probably also thesalt-pans at SantaMaria on Sal,but these are likelyto be SantaLuzia, Ringed Plover Charadrius hiaticula, Grey Plover wanderersfrom the PedraLume colony. Pluvialissquatarola, Sanderling Calidris aiba, Whimbrel Numeniusphaeopus and Greenshank Tringa nebularia are The KentishPlover is widespread and common on Sal, widespreadin small numbers, while Turnstones Arenaria Boavistaand Maio,and locallycommon on Santiagoand Sao interpresfrequent the rockyparts of the shore,as wellas salt- Vicente.It occursalong the shores and at salt-padsand pans,lagoons and waste dumps near coastal villages. lagoons,as wellas on drycoastal plains. Because of lackof suitablehabitat, it is onlyfound in smallnumbers on the On Fogo,Brava, Santo Ant•.o and S•.o Vicente, Ringed remainingislands, and so far breedinghas not been estab- Plover,Grey Plover, Whimbrel, Greenshank and Common lishedthere. The localpopulation appears to be resident. SandpiperActitis hypoleucos are encounteredoccasionally, Bannerman& Bannerman(1968) thought that groups of butmostly singles, rarely more than two individuals of a migrantswere passing through Sao Vicente in February- speciesat a time.Sanderling and Turnstone are moreoften March1966. However, no significant numbers of migrantsare metwith- the formeron the few beaches(of blackvolcanic thoughtto visitthe CapeVerde Islands. The only observa- rock),the latteralong the rockyshores and nearcoastal tionspossibly indicating migration were of a looseparty of villages- buteven these seldom number more than 10 birds c.100 birdsat the lagoonand salt-pans north of Vilado Maio, in a group. Maio,on 26 May 1989 (whichseems to be ratherlate for passagemigrants), and a groupof 18 onthe drycoastal plain The onlywaders encountered on the uninhabitedislets of southof Tarrafal,Santiago, on 12 April1990. The fluctuations Rombos,Branco and Raso, were single Whimbrels and Greenshanksand smallparties of Turnstones. Table5. Waderscounted at PedraBadejo Lagoon, Santiago. Results of wader counts at five sites on four islands are 21 Oct 9Nov 2Mar 10Apr 14May 1988 1988 1990 1990 1989 presentedin Tables 1-5. In general,numbers at thevarious sitesappear to remainrather stable from late August until Black-wingedStilt H. himantopus 5 2 little RingedPlover C. dubius 1 3 2 1 April.Numbers decrease in May,and the count at the Mindelo RingedPlover C. hiaticula 6 1 0 13 14 sewage-farmin June (Table 2) showsthat only few birds Kentish Plove C. alexandrinus 15 + 16 16 + remainthat late in the season.Judging from my own sightings GreyPlover P. squatarola 2 2 SanderlingC. alba 6 + 3 10 5 andboth published and unpublished data, small numbers of Little Stint C. minuta 2 wadersseem to oversummer.There are Juneand August CurlewSandpiper C. ferruginea 17 25 recordsof nearlyall waders that occur regularly in the Cape KnotC. canutus .- 1 1 RuffP. pugnax 6 4 VerdeIslands (Hazevoet in prep.). July records are rare, WhimbrelN. phaeopus 1 1 probablyreflecting a lack of observersduring that month SpottedRedshank T. erythropus 1 ratherthan a genuineabsence of birds.Very few observers Redshank T. totanus 3 GreenshankT.nebularia 2 6 1 3. 5 appearto havevisited the islandsin July. WoodSandpiper T. glareola 1 3 4 10 ' CommonSandpiper A. hypoleucos 2 12 1 3 1 The peak,both in numbersand in species,at PedraBadejo TumstoneA. interpres 10 15 12 25 13 Lagoonon 9 November(Table 5), occurredafter heavy rains

48 whichfilled the lagoonwith water and deposited plenty of mud DISCUSSION andplant material in it,offering ideal feeding opportunities for waders.This was attractiveto specieswhich apparently are Dueto the scarcityof suitablehabitat, only limited numbers of presentin the islands in small numbers but usually remain migrantwaders winter in the CapeVerde Islands. The undetected.The highnumbers of CurlewSandpiper C. extremerarity of Knotand Dunlin,among the mostnumerous ferrugineaand Sanderling at thePedra Lume salt-pans on 23 winteringwaders along the WestAfrican shores, is remark- December(Table 1) are noteworthy,probably not being due able.Most probably, the absenceof mudflatsis the limiting to roostingmovements only, and possibly representing a factorfor these species. On the WestAfrican mainland, distinct influx. Dunlinsate abundanton the Bancd'Arguin, Mauritania, but muchscarcer further south (Smit & Piersma1989). Whimbrel Apartfrom the locationsincluded in Tables1-5, only few sites andGreenshank occur in lowdensities along coasts through- werefound where more than a fewwaders occurred together. outthe archipelago,both on rockyand sandy shores. Small Thesewere the salt-pans at SantaMaria on Sal (25 Novem- partiesof Sanderlingscan be foundwherever there are sandy ber1988: Black-winged Stilt 4, RingedPlover 2, Kentish beaches,which also support the occasionalRinged Plover Plover20, LittleStint ½. minuta 1, CurlewSandpiper 2, Dunlin andGrey Plover, although these two are foundon reefsas C. a/pina1, Bar-tailedGodwit Limosa/apponica 1, Turnstone well.Species exclusively observed at salt-pans,lagoons or at 10);the lagoon north of PortoFerreira on Boavista (20 May thesewage farm included, Little Stint, Curlew Sandpiper, 1989:Kentish Plover 2, Sanderling30, Greenshank1, Redshankand Wood Sandpiper. In viewof the manyrocky Turnstone10); and the reefs south of Mindelo,S•.o Vicente shoresin the CapeVerde Islands, it is notsurprising that the (26 March1990: Ringed Plover 25, KentishPlover 10, Ruff Turnstoneshould be thecommonest wintering wader. Also, Philornachuspugnax 1, Whimbrel5, Turnstone15). The the speciesis a scavengeraround coastal human settle- Dunlinat SantaMaria was the onlyone seen in the islands ments,a nichenot exploited by the otherwaders. during1986-90. In the Cape Verde Islands the species is a raremigrant of whichthere are only c. 10 records(Hazevoet Notwithstandingthe smallnumbers, nearly all waderspecies inprep.). The Bar-tailed Godwit, first recorded only in 1969 thatcommonly winter in WestAfrica have now been shown to (Frade1976) and formerly considered a vagrant, has now reach- at leastoccasionally- the Cape Verde Islands. One beenshown to be a regularwinter visitor in smallnumbers, notableexception is the CurlewN. arquata,the onlyrecord of withrecords from October to February(Hazevoet 1990). The whichis an unsubstantiatedclaim by Alexander (1898). The partyof 25 RingedPlovers near Mindelo was unusual and onlyexclusively Nearctic wader recorded is the Lesser constitutesthe largestflock observed. GoldenPlover P. dominica(cf. Appendix 1), butit is likelythat more will be found as field work continues. Turnstones,by far the mostcommon wader in the Cape VerdeIslands, were often found around coastal villages ACKNOWLEDGEMENTS foragingat rubbishdumps and on fish offal. For instance, aroundSal Rei,the mainvillage on Boavista,c. 100 Myfirst two journeys to the CapeVerdes were made aboard Turnstoneswere present on various dates from September to the SV Siriusand MV Planciusrespectively. During 1988-90, May. mywork with the NationalParks and Protected Areas Pro- gramwas supported by the InternationalCouncil for Bird Detailsof the rarerspecies included here have already been Preservation(Netherlands Section), the Netherlands Founda- publishedelsewhere (Hazevoet 1988, 1990). These are tionfor InternationalNature Protection (van Tienhoven LapwingVane#us vane#us (first record), Spotted Redshank T. Stichting),The J.C. van der HuchtFonds, the Martinade erythropus(first record), and Knot C. canutus(second BeukelaarStichting, the NetherlandsSociety for the Protec- record).Another Knot (third record), on 2 March1990 (Table tionof Birds(Vogelbescherming), and the Ministryof 5), wasinadvertedly omitted from the earlier publication. Agriculture,Nature Management and Fisheries of the Nether- lands.In theCape Verde Islands, working facilities were Theonly other species observed and not mentioned above or providedby the Instituto Nacional de Investiga•oAgr•ria listedin Tables1-5, was a CollaredPratincole Glareola andthe Ministryof RuralDevelopment and Fisheries. Lynn pratincolaat Calheta,Maio, on 27 May1989: the third record Millerprovided good company in the field. I shouldlike to forthe Cape Verde Islands (Hazevoet 1990). thank Marc van Roomen and Jan Wattel for their comments on a draftof thispaper.

49 REFERENCES APPENDIX1. Waderspecies recorded in the Cape Verde Islandsbut not observed by the presentauthor. Data from Alexander,B. 1898.An ornithologicalexpedition to the Cape Hazevoet(in prep.). VerdeIslands. Ibis Ser. 7(4): 74-118 OystercatcherHaematopus ostralegus (6 records) Bannerman,D.A. & Bannerman,W.M. 1968.History of the birdsof theCape VerdeIslands. Birds of theAtlantic islands. AvocetRecurvirostra avosetta (2 records) Vol.4. Oliver& Boyd,Edinburgh. LesserGolden Plover Pluvialis dominica (3 records) Frade,F. 1976.Aves do arquipelagode CaboVerde (Collec•;aodo Centro de Zoologiade J.I.C.U.).Garcia de Orta JackSnipe Lymnocryptes minimus (one record) (S(•r.Zool.) 5: 47-57. MarshSandpiper Tringa stagnat#is (2 records) Hartog,J.C. den. 1990. Birds of the CapeVerde Islands. Noteson species observed (9 August-10 September1986), GreenSandpiper Tringa ochropus (3 records) distribution,migration, status, origin and conservation. tour. Forschungsinst.Senckenberg, 129:159-190 GreyPhalarope Phalaropus fulicarius (uncommon migrant in CapeVerde Seas, c. 10 records) Hazevoet,C.J. 1988.Lapwing Vanellus vanellus, new to the CapeVerde Islands. Malimbus 10:221-222.

Hazevoet,C.J. 1990. Noteson newand raremigrants in the STOP PRESS CapeVerde Islands. Bull. Br. Ornithol. Club 110: 207-212. A visitto the CapeVerde Islands between January - April Hazevoet,C.J. In prep.Check-list of theBirds of the Cape 1991 resultedin the third island recordfor Avocet,the VerdeIslands. British Ornithologists' Union. first recordof CurlewNumenius arquata, the second SpottedRedshank and the first NeararcticWhimbrel N.p. Lambert,K. 1980.Beitr•ge zur Vogelweltder Kapverdischen hudsonicus. Inseln.Beitr. Vogelkd. 26:1-18.

Naurois,R. de & Bonnaffoux,D. 1969. L'avifaunede I'11edu $el (11hado Sal,Archipel du CapVert). Alauda 37:93-113.CI

Norrevang,A. & Hartog,J.C. den. 1984.Bird observations in theCape Verde Islands (4-22 June 1982). tour. Forschung- sinst.Senckenberg 68:107-134.CI

Smit,C.J. & Piersma,'•,'. 1989. Numbers,midwinter distribution,and migration of waderpopulations using the East Atlanticflyway. In: H. [.3oyd& J.-Y. Pirot(eds.). Flyways and reservenetworks for •vater birds. IWRB Special Publication No. 9.

Summers-Smith,J.D. 1984.Bird notes from the CapeVerde Islands.Bull. Br. 'Orr. ithol. Club 104:148-149.