Dunlin Calidris alpina migration across Tiligul Liman,

Yuri Zharikov

Zharikov,Y. 1995. DunlinCalidris alpina migration across Tiligul Liman, Ukraine. Wader Study GroupBull. 76: 33-36. Zharikov, Y., 14, Vegera St., ½/15,Odessa 270008, Ukraine.

INTRODUCTION water pondswhich quickly warm up in springand are extensivelyused by migrantand residentwaders and The north regionis an importantstop-over area waterfowl as feeding and restingsites. for shorebirdsmigrating in spring(Chernichko eta/. 1991) from as far as west and south Africa to their breeding groundsin northernEurope and Asia (Hale 1980). Tiligul Liman in Ukraine is one of several stagingsites in the north-westBlack Sea Region used by migrating shorebirdsfor 'refuelling'and concurrentlycompleting moult. Dunlin Ca/idrisa/pina is the most numerouswader speciesusing the area.

The nominatesubspecies comprise the main bulk of the Dunlinpopulation migrating across Tiligul. Ca//dr/sa. schinzi/,which principally use the east Atlanticflyway for migration(Pienkowski & Dick 1975) occur in the NW Black Sea regiononly accidentally(Gromadzka 1989). The easternsubspecies (sakha//na Dunlin), which are accidentallyfound elsewherein Europe (Cramp & Figure1. The BlackSea and the area of the studysite. Simmons1983)and in the MediterraneanRegion (Mullie & Meininger1981) also may appearsporadically at Tiligul as well (Chernichkopers. comm.). Finally,birds known as centraftsDunlin (intermediates between a/p/na and sakha/ina(Hale 1980) whose breedinggrounds lie on the Taymyr Peninsula)and knownto migrateto Europe (Meininger& van Swelm 1989) also use the BlackSea- MediterraneanFlyway in spring.

In this paper data on the Dunlinspring migration across TiligulLiman are analysedand an attempt is made to suggestthe final destinationand migrationroute of the birdsbased on biometrics,departure body mass and the timing of migration.

STUDY AREA AND METHODS Figure2. TiligulLiman. The studywas conductedfrom the beginningof May (the end of April in 1990) to mid June 1990 - 1992 at the lower In 1990, the field season started two weeks earlier than in part of TiligulLiman (46o45 ' N, 31ø 10' E) (Figures1 & 2). both 1991 and 1992. The firstbirds were capturedin The term "liman"refers to a usuallyland-locked salt water 1990 on 20 April,on 10 May in 1991 and on 9 May in pondwhich was formerlya rivermouth flooded by the 1992. Duringthe three field seasons a total of 207 Dunlin sea. Such water bodies are characteristic of the NW were capturedusing walk-in traps adaptedto the local BlackSea region. Tiligulis one of the largestlimans of conditions(Chernichko 1984). Nine trapswere used in this type. It is 55-80 km long (dependingon the annual 1990 and 1991 and seven in 1992. amountof precipitation)and up to 4.5 km wide. Salinity at the lower part of the liman is close to that of the north- In all three years capturedbirds were classifiedas either westernBlack Sea (0.012-0.013%)while at the upperpart secondyear or olderthan secondyear (see Prater eta/. it dropsto 0.004%. Currentlythe limanis separatedfrom 1977). Only in 1992 were birdssexed on the basis of their the BlackSea by a naturalsand spitsome 4 km longand breedingplumage (Ferns & Green 1979). 5-7 km wide. This area has many interconnectedshallow

33 Biometricdata presentedin this paper are from all Bill and winglength capturedbirds. Billlength (exposed culmen) was measuredwith callipersto the nearest 0.1 mm. Wing The averagebill length of Dunlinfor the threeyears Was length(maximum cord) was measuredwith a rulerto the 33.6 mm (n = 197; SD = 2.4; 95% C.I. 33.3 - 34.0). nearest 1.0 mm. Weight was measuredto the nearest 0.5 with balancescales. Minitabsoftware package was No significantdifference (ANOVA p -- 0.576) in billlength used for statisticalanalysis of the data. Fat load was was observedbetween three years (frequency distribution estimatedby the equation: FM = 0.548'BM - 0.572'B - 2.11 of the bill lengthsis shownin Figure3). Averagebill lengthof Dunlinstaging at Tiliguldid not seemto change where FM = fat mass(g), BM = bodymass (g) and B = bill significantlyduring the stopoverperiod in 1990 (ANOVA length(mm), developed for Dunlindeparting from NW p = 0.983) and 1992 (ANOVAp = 0.438) (Table1). Africain spring(Piersma & van Brederode1990; Piersma However,in 1991 it seemedto increasein late May pers. comm.). comparedwith the beginningof the month(ANOVA p = 0.004).

RESULTS Table 1. Seasonalchanges in billlength (mm) of DunlinCalidris alpinacaptured at TiligulLiman in spring1990-1992. Monthsin Romannumerals (IV = April,V = May etc.). Timingof migration Year Period n Mean SD Range Eventhough Chernichko (1992) reportedthat the first Dunlinarrive to Tiligul as early as the end of March, the 1990 20.1V-30.1V 14 33.4 1.6 29.5 - 36.5 1 .V-10.V 6 33.1 1.2 31.7 - 35.2 majorityof the migratingpopulation arrives at the 11 .V-20.V 17 33.7 2.0 29.9 - 36.8 beginningof May. Thiscoincides with general departure 21 .V-30.V 29 33.6 1.9 31.1 - 35.5 of shorebirdsbreeding in northernSiberia from the >30.V 4 33.5 1.9 31.1 - 35.5 MediterraneanRegion (Piersma & van De Sant 1992). TOTAL 1990 70 33.5 2.2 29.5 - 37.6 Usuallyby the secondweek of May, the number of birds 1991 10.V-20.V 13 31.7 2.2 28.0 - 36.4 reaches its maximum, and stays at this level until around 21 .V-30.V 54 34.3 2.5 28.5 - 40.4 >30.V 9 34.5 2.5 30.2 - 37.1 25 May. (In 1994 the firstflock of approximately200 TOTAL 1991 76 33.9 2.6 28.0 - 40.4 Dunlindeparted on 29 May). Afterthat Dunlinnumbers 1992 10.V-20.V 8 34.1 2.8 29.0-37.3 declinequickly and the last individualsleave by 10 June. 21.V-30.V 23 33.1 2.4 29.6-37.6 >30.V 20 33.7 1.8 30.6- 38.1 Counts made in previousyears suggestthat c. 4,000 TOTAL 1992 51 33.5 2.2 29.0- 38.1 Dunlinmay be presentat Tiligulat one time (Chernichko pers. comm.) (in late May 1994 c. 3,500 Dunlinwere 15- countedin the area). However,turnover of the birds remainsunknown and the total size of the population usingthe site has therefore not been estimated. 10

Departingflocks left aroundor after sunsetand flew in 5 easterly(along the coast line) and north-easterly directionsbut it wasnot clear whether this corresponded with their ultimate destination. 0 I I I

Moult Bill len9th (mm) Figure3. Percentfrequency distribution of billlength (mm) of Dunlin Upontheir arrivalto Tiligulmost (over 90%) of the Dunlin Calidrisalpina captured at TiligulLiman in spring1990-1992 (n = were moultingtheir contourfeathers, with less than 10% 197). still-inwinter plumage. By 25 May morethan 95% of the 20- stagingpopulation had finishedmoult and were in full breedingplumage.

Recoveries

A bird(first winter) ringed at Tiligul(46o45 ' N, 31ø 10' E) on 30 May 1991 was recovered at the Vistula Mouth, 0 , Poland(54 ø 20' N, 18ø 56' E) on 24 July1991 during I I I I I I I I l autumnmigration. On 12 May 1992 an adultbird ringed at the VistulaMouth, Poland on 31 July 1991 was Wing length (mm) recovered at Tiligul. Figure4. Percentagefrequency distribution of DunlinCalidris alpina wing length(mm) caughtin spring1990-92 (n = 203).

34 The average wing lengthfor the three years was studiesconducted at Tiliguldemonstrated that at the end 117.2 mm (n = 203; SD = 3.5; 95% C.I. 116.7 - 117.6) of Apriland the beginningof May up to 96% of Dunlinat (see also Figure4). The estimatedaverage bill and wing Tiligulare alreadyin the processof moultingcontour lengthswere 32.2 mm and 114.9 m for males and 35.2 feathers and only 33% are still moultingin the second half mm and 116.6 mm for females respectively(Table 2). of May (Bukovetskaya1992). In this studymore than 95% of Dunlinwere in their full breedingplumage after 25 Table2. Meanbill and wing lengths (mm) in maleand femaleDunlin May. The completionof moultseemed to be followedby a Ca/idrisa/pina captured at TiligulLiman in spring1992. rapidincrease in the bodyweight (Figure 5).

Sex n Bill SD CV Wing SD CV

Male 27 32.2 1.9 5.9 114.9 2.8 2.3

Female 20 35,1 1.7 4.8 116,6 3.4 2.9

70- Weight (g)

1

I I i i i 20,4 30.4 10,5 20.5 30.5 Weight (g)

Weight (g) I i i i i 20.4 •0.4 •0.5 20.5 •0.5 Figure6. Percentfrequency distribution of bodyweight (g) of Dunlin Calidrisalpina captured at Till.JulLiman after 25 May: Figure6.1 in Figure5. Seasonalchanges in (above)weight (g) and (below) 1990 (n = 17); Figure6.2 in 1991 (n = 45), and Figure6.3 in 1992 (n estimatedfat load (g) (see Methods)of DunlinCa/idris a/pina = 40). capturedat TiligulLiman in spring 1990-1992. Solidline: 1990 (weight:r = 0.664, p = 0.000, and n -- 70; fat load:r = 0.732, p = 0.000, and n = 67) The homogeneityof the populationis furtherindicated by Dashedline: 1991 (weight:r = 0.396, p = 0.000, and n = 76; fat load: the constantaverage bill lengthof capturedDunlin r = 0.342, p = 0.003, and n = 74) throughthe stagingperiod (exceptmaybe for 1991). This Dottedline: 1992 (weight:r = 0.371, p = 0.007, and n -- 51' fat load:r is unlikethe expectedsituation if mixed breeding = 0.444, p = 0.001, and n = 49). populationswere present(Goede e! a/. 1990). It also indicatesthat male and female Dunlinarrive at Tiligul Body weight together - consistentwith the conclusionof Chernichko (1992). The estimatedsex ratio of males and females was 1.4: 1 in this study(1992) and 2:1 accordingto Bodymass in Dunlincaptured at the end of Apriland in Chernichko(1992). He believedthat the majority(but not the beginningof May on average was c. 55 g. Further,the all) of the birds(61%) belongto the populationbreeding to increase in body mass and estimatedfat load of the the east of the Ob Riverpossibly as far as western Dunlinfollowed (Figure 5). By 25 May when Dunlin Taymyr Peninsula(Gromadzka & Ryabitsev,WSG 1992 starteddeparting, the birds'body weight in the sample OdessaConference), attributing the restto a/pinaDunlin rangedfrom 50 g to 75 g with slightlyover 40% of those of north-westernSiberia (Yamal Peninsula). weighingmore than 68 g. Approximately40% of Dunlin had a bodyweight between58 g and 68 g and 20% of Dunlinhad bodyweight less than 58 g (Figure6). Accordingto Cramp & Simmons(1983) the bill lengthsof bothmale and female Dunlincaptured at Tiligulwere similarto those of subspeciessakha/ina (32.0 mm and 35.1 mmfor malesand females respectively).These are DISCUSSION also close to measurements of Dunlin from the central Taymyr (31.9 mm and 34.8 mm (Kania 1990)), and The fact that the Dunlinpopulation staging at Tiligularrive Tunisianwintering population (34.2 mm and 33.0 mm and departalmost simultaneously and simultaneously (combinedsexes at two differentlocations (Dijk 1986)). finishtheir moultimplies that birdsnot only arrivefrom the same place (whichmay be Tunisia(Gromadzka 1989; Mean wing lengthwas 117.2 mm (see alsoTable 2) close Chernichkopers. comm.)and/or elsewhere in the southern to the measurementsfor Calidrisa. a/pinagiven by Cramp and south-easternMediterranean Region (Mullie & & Simmons (1983). Meininger1981 )) but also originatefrom the same breedingarea (presumablycentral ). Previous

35 Duringthe lastweek of May/beginningof June, after Castro,G., & Myers,J.P. 1989. Flightrange estimates for havingcompleted moult Duniin quickly increase their body shorebirds. Auk 106: 474-476. weightby depositinglipids for the final part of their Chernichko,I. I. 1984. Traps for birdsand resultsof their use in the northwardmigration. If uponarrival at Tiligulsome birds north-westernBlack Sea Region. Tr. Oksk.gos. zap. 15: 72- may carry as littleas estimated2-3 g of fat, in those 86. (In Russian.) Duniinwhich are readyto departthe fat Icad may exceed Chernichko, 1.1.,Grimchenko, A.B., & Sickhan, V.D. 1991. Waders 18 g (Figure 5b). of the Sirash Gulf,Azov-Black Sea. WaderStudy Group Bull. 63: 37-38. Though rather similar in their moult, timing and body measurements,Dunlin found at Tiligulin springseem to Chernichko,I.I. 1992. In: Volnstvenski,M.A. (ed.) Seasonal showconsiderable variation in their departurebody mass migrationsof birdsin the Ukraine. Kiev. NaukovaDumka: 182-184. (In Russian.) (Figure 6). Thus birds may have accumulateddifferent amounts of fat on different migrationroutes. Heavy birds Cramp,S., & Simmons,K.E.L. (eds). 1983. The birdsof the (70-75 g and more) can probablycover the distanceto westernPalearctic. Vol. 3. OxfordUniversity Press, Oxford. their proposedbreeding grounds in north-west- central Danilov,N.N. Ryzhanovskiy,V.N. & Ryabitsev,V.K. 1964. Birdsof Siberiain 'one giant hop' (Meltofte1991); their estimated Yamal. Nauka, Moscow. (In Russian.) flightrange being 3,200 km (Castro & Myers 1989). The lighterbirds which comprise 20% of Tiligulstaging Dijk,A.J. van. 1986. Winterin,qwaders and waterfowlin the Gulf of populationmay use two possiblelonger ways which Gabes, Tunisia,January- March 1984. WlWO Rep. 11 Zeist, 206 pp. howeverwill allowthem to feed en route. The first option may be to fly northwardsto the White Sea coast (2,100 Ferns,P.N., & Green, G.H. 1979. Observationson the breeding km) and then migratealong the coast (Meltofte1991). plumageand the pre-nuptialmoult of dunlins,Calidris alpina, Alternativelythey may fly eastwardsto the Volga capturedin Britain. Gerfaut69: 286-303. (1,100-1,200 km) and then moveto the northalong the Goede,A.A., Nieboer,E., & Zegers,P.M. 1990. Bodymass Volga-KamaBasin (Chernichko pers. comm.). In both increase,migration pattern and breedinggrounds of Dunlins, cases some of these migrantswill not be in time to breed Calidrisa. alpina,staging in the DutchWadden Sea in spdng. but are neverthelessknown to arrive on their breeding Ardea 78: 135-144. grounds(Chernichko pers. comm.). Gromadzka,J. 1989. Breedingand winteringareas of Dunlin migratingthrough southern Baltic. OrnisScand. 20: 132-144. OverallDunlin departure from Tiligul at the end of May - beginningof June seems to fit the general timing of Hale, W.G. 1980. Waders. Collins, London. breedingfor the Dunlinfrom north Siberia (polar climatic Kania,W. 1990. The primarymoult of breedingDunlins Calidris zone) where they start breedingfrom the second/third alpinain the centralTaymyr in 1989. Wader Study GroupBull. week of June (Danilov et aL 1984). Their measurements 60: 17-19. were similarto those of eastern Calidrisa. alpina(Calidris Meltofte,H. 1991. The northernDunlin puzzle. Wader Study Grcup a. centralis(Stepanyan 1990)). Their estimatedflight Bull. 62:15-17. range may allowthem to reach areas from Yamal Peninsulaand to the east. These not very solid facts may Meininger,P.L., &van Swelm,N.D. 1989. Steltlopersin de neverthelesssuggest that Dunlinfound at Tiligulin spring Oosterschelde,biometrisch en ingonderzoekin voorjaar1984 en 1985. RijkswaterstaatDeinst Getijdewateren nota GWAO- breed as far to the east as the Yenisey Delta. 89.1009,Stichting Ornithologisch Station Voome, Middelburg/ Oostvoorne.

Mullie,C., & Meininger,P.L. 1981. Number,measurements and ACKNOWLEDGEMENTS stomach contents of Dunlins, Little Stints and Kentish Plovers fromLake Manzala,Egypt. WaderStudy Group Bull. 32: 25- Data for this paper were collectedduring the annual 29. Odessa State UniversityDepartment of Biologyshorebird- Pienkowski,M.W., & Dick,W.J.A. 1975. The migrationand ringingprogrammes at TiligulLiman and I am extremely winteringof Dunlin Calidrisalpina in north-westAfrica. Ornis gratefulto the faculty:Vladimir Stoilovski,Dmitri Scand. 6: 151-167. Kivganov;and students:Maxim Stepanov,Vitali Popeliukh who consultedand helpedme throughoutthis period. Piersma, T., & van Brederode, N.E. 1990. The estimationof fat reservesin coastalwaders beforetheir departure from AnatoliKorzyukov kindly supplied me with reference NorthwestAfrica in spring. Ardea78: 221-236. material. My specialthanks to losifChernichko, J. Sherman Boates, and Jadwiga Gromadzka for their Piersma,T., & van de Sant,S. 1992. Pattemand predictabilityof valuablecomments and remarkswhich improved the early potentialwind assistance for wadersand geese migratingfrom West Africa and the Wadden Sea to Siberia. Ornis Svecica 2: drafts of this paper. 55-66.

Prater, A.J., Marchant, J.H., & Vuodnen, J. 1977. Guide to the REFERENCES identificationand ageingof Holarcticwaders. BTO Guide 17, Tring.

Bukovetskaya,N. 1992. DunlinCalidris alpina migration in the north- Stepanyan,L.S. 1990. Conspectusof the ornithologicalfauna of the westernBlack Sea Region. Thesis,Odessa State University. USSR. Moscow, Nauka. (In Russian.)

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