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In search of the Slender-billed Curlew (Numenius tenuirostris) Preliminary results of an expedition to wetlands and waterbirds of the Baraba and Karasuk steppe in the south of West Siberia, Russian Federation, 17 May - 22 June 1997.

Gerard C. Boere and Alexsandr K. Yurlov

Boere,G.C. & Yurlov,A.K. 1998.In searchof the Slender-billedCurlew, Numenius tenuirostris. Wader Study Group Bull. 85: 35-38.

G.C.Boere, Voorstraat7, 4153 AH Beesd,the Netherlands(correspondence); A.K. Yurlov,Institute of Ecology,Siberian Branche Russian Academy of Sciences,11 Frunzestreet,630091 Novosibirsk, Russian Federation.

INTRODUCTION In the period 17 May - 22 June 1997, GerardBoere (in a The Slender-billed Curlew Numenius tenuirostris is one of the privatecapacity as WIWO co-worker)and SashaYurlov rarestbirds in the world; total populationestimates vary (SiberianBranche Russian Academy of Sciences)undertook an betweenonly 100-400individuals. The speciesis includedin expeditionwith a Russianfour-wheel drive UAZ 469 army car many Red Data Books and in the highestconservation in orderto try to visit 11 out of the 22 areasidentified by categoriesof many internationalconventions such as Annex I Danilenko et al (1996). in the Novosibirsk,Altaisk and Omsk of the Bonn Convention. In the case of the Bonn Convention, regions.This reportgives some preliminary results of the thereis evena separateMemorandum of Understanding expedition;a full accountwill be publishedas a WIWO report, betweenthe governmentsinvolved. expectedto be readyby the end of 1998.

A full historicalstatus report was given in the ICBP (now BirdLife International)publication by Gretton(1991). More ROUTE, CONDITIONS AND AREAS VISITED recentlyDr Nowak of the Bonn ConventionSecretariat The expeditioncovered about 5,000 km following a route(see summarisedthe datacollected since 1991 (1996, unpublished Figure1.) throughBamaul to the southernAltaisk Region, via reportBonn Convention Secretariat). Nowak's report many marshesand lakes,to Lake Kulundinskoe,Karasuk and mentionsa groupof about20 birdswintering in southItaly in the surroundingarea. Fromthere it led on to the Lake Chany 1995/1996and flocks of up to 50 birdswintering along the region(islands, lake shoresand surroundingsteppe areas); then southerncoast of Iran. Almostevery year, single birds or 2-3 north to Barabinsk, Ust-tarka and then Tara and the marshes individualstogether are observedin countriesin the where, in 1924, the last Slender-billed Curlew nest was found. Mediterraneanregion. EU subsidies,under the LIFE From Tara, we went south to Lake Tenis and via Omsk and Programme,have beengiven to someof thesecountries, for Tsjerlakto the vaststeppe region on the borderwith exampleGreece, to conserveareas where Slender-billed Kazakhstan.Finally, we travelledvia Lake Chanyto Kargat Curlewshave regularly been observed. and Lake Ubinskoe back to Novosibirsk. The weather was generallyhot anddry with muchdust and many mosquitos. The presentbreeding area is unknown.The lastnest was Heavy rainfall forcedus out of the Lake Ubinskoearea. Road discoveredin 1924 by Ushakov,in the marshessouth-west of conditionswere very Siberian:a few werebitumen, the rest Tara, a town on the river Irtish about 250 km north of Omsk. were sandytracks and/or cross-country routes which we Severalattempts in the period 1990-1996to rediscoverthe followedwith thehelp of reasonabletopographic maps and in breedingarea have sofar failed. Recently,Danilenko et al. particular,the local peopleand herdsmen.Nonetheless, the (1996) analysedand discussedthe causesof the declineof the generalroad conditionsand navigationconsumed a Slender-billedCurlew andconcluded that the breedingarea is considerableamount of our time duringthis expedition. not in thetaiga but insteadin wet areasin theforest-steppe and northernsteppe zones of west Siberia. Basedon We managedto visit sevenout of the eleventarget areas which biogeographicalinformation, these authors described 22 areas were, in principle,within our range. However,four turnedout wherethe chanceof finding breedingSlender-billed Curlews to be too far out of the maximumrange that we couldcover mightbe higherthan average. given the time available. These sevenareas were: Altaiske Krai/Altei river (no. 15); area southof Novosibirsk water 36

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•'. '-x %',. 37 reservoir(no. 13); Burla fiver valley (no.12); southshore of Calidris alpina, Curlew SandpiperCalidris ferruginea, Little Malye Chany(no. 10); areabetween Om andIrtish rivers (no.9) Stint Calidris minuta, and Red-neckedPhalarope Phalaropus northernarea of Lake Tenis (no.8) and the eastcomer of Lake lobatus. Ubinskoe (no.11). In total, 120 more or lesssystematic point countswere made We foundthat four of theseareas have been completely coveringa rangeof steppeand marsh/lakehabitats. All are on destroyedby humanactivities such as over-grazing,building of separatecensus sheets and will be fully recordedin the final drainage/irrigationchannels through large steppe areas, change report. A summaryof all birdscounted is presentedin Table 1. of steppeinto arableland etc. Thesewere areanumbers: 15, Many lakesand marshes, shown on the maps,no longer 13, 10 and 9. The Burla river area should remain on the list of existed. This is not only due to humaninfluence but also potentialareas. Two areasare a high priority to be revisited becauseof the so far little-understoodnatural cycles of water and searchedmore carefully; these are the areasnorth of Lake levelsin a wide rangeof the Siberianlowlands (Krivenko Tenis and north of Lake Ubinskoe. We also visited the marshes 1991). Large lakesin the 1960sare now marshesor dry valleys whereUshakov found the last knownbreeding site. This area and excellentwader breeding sites. We discoveredwith haspreviously been visited by Dr Yufiov togetherwith Dr coloniesof up to 200 pairsof Black-wingedStilts Himantopus Grettonand Dr O' Sullivan;the lastvisit wasthree years ago. himantopusin largevalleys with shallowwaters, which had This areahad alsochanged completely. Remaining steppe beendry dustyplaces for morethan severalyears. Somerivers plotson the higherparts of the marsheshave been turned into in the Novosibirskregion had levels of 1-2 m abovenormal, wheat fields; new birch tree roads(in Russian:Gat) have floodinghuge areas of grasslands,whereas in other areasthe openedup the areaand the originalopen marsh of the last water level in the rivers was lower. This makescomparison in breedingsite was now completelycovered with youngforest. time betweenareas very difficult and many of the breeding waterbirdsmust be nomadicwith respectto their annual Local farmers,who we met at the placewhere, in 1924, there breedingsites. was a village,informed us thatthe village wastotally abandonedand destroyed in the late 1960sand that the water We discovereda numberof new breedingsites of waterbirds table in many lakes had droppeddue to agriculturalactivities, listed in the Red Data Book of the Russian Federation, for thusstimulating the growthof treeson the formerwet marshes. example: The local museum in Tara did not have a stuffed Slender-billed ß DalmatianPelican Pelicanus crispus; group of about20 Curlew,but did have Whimbrel Numeniusphaeopus and non-breedingbirds in the Burla valley. CommonCurlew Numeniusarquata. ß SociablePlover Chettusiagregaria; onepair, with nest, near Karasuk. ß Black-wingedStilt Himantopushimantopus; many new RESULTS, WADERS AND OTHER BIRD OBSERVATIONS coloniesdiscovered, some of them with hundredsof No breedingSlender-billed Curlews were discoverednor breedingpairs. observed.During the expedition,we interviewedtens of ß Asian DowitcherLimnodromus semipalmatus; five new people:'cowboys', hunting inspectors, fishing inspectors, breedingsites discovered: one northof Lake Tenis(with farmers,local wardensof natureand huntingreserves etc. In nest/oneegg), which is far beyondthe presentlyknown all caseswe showedthem a postcardpicture of a Slender-billed breedingrange. Curlew (a large stockwas kindly madeavailable by the ß Avocet Recurvirostraavocetta; fewer than Black-winged Secretariatof the Bonn Convention)and left it with the people Stilt, but foundin small numbersat many more placesthan with the addressof Dr Yurlov. It was remarkablethat everyone ever known before. knew the othertwo Curlew species,but nonehad ever seenthe ß White-wingedBlack Tern Chlidoniasleucopterus; Slender-billedCurlew. Many of thesepeople knew their birds particularlycommon this year; many very largecolonies extremelywell, identifyingcorrectly many otherwaders such discovered;in total a minimumof 12,000 breedingpairs as Black-tailedGodwit Limosalimosa and RedshankTringa counted. totanus;both specieswere commonin the whole areacovered ß Great Black-headedGull Larus ichthyaetus;new colony by our expedition. discovered on a small island in Lake Kulundinskoe. We estimatedabout 450-500 breedingpairs. It is the second The samewas true for specieslike Lapwing Vanellusvanellus colonyof this rare speciesin the southof West Siberia. andMarsh SandpiperTringa stagnatilis. CommonCurlew and Whimbrelwere observedregularly. In onecase, a Whimbrel Clearly the southof West Siberiais an extremelyimportant was identifiedas the rare steppesubspecies Numenius wetlandand waterbirdarea, both for breedingand migrating/ phaeopusalboaxilliaris. Arctic breedingwaders were still moultingwaterbirds and worthmuch more attentionthan migratingthrough the areaand in late May/early Junein presentlyis the case;even without a rediscoveredbreeding site particular,we observedmany flocks of speciessuch as Dunlin of the Slender-billed Curlew! 38

Table 1. Totalnumber of birdscounted during expedition (20 May- 18 June 1997)

Gavia arctica 3 Charadrius dubius 34 Podicepscristatus 89 Charadriushiaticula 1 Podicepsauritus 5 Pluvialisdominica 5 Podicepsnigricollis 95 Pluvialissquatarola 20 Pelicanuscrispus 23 Chettusiagregaria 2 Botaurus stellaris 5 Vanellus vanellus 655 Egrettaalba 1 Calidris minuta 204 Ardea cinerea 48 Calidris temminckii 32 Cygnusolor 14 Calidrisferruginea 138 Cygnuscygnus 180 Calidrisalpina 342 Anseranser 215 Philomachus pugnax 343 Tadornaferruginea 10 Gallinagogallinago 57 Tadornatadorna 310 Gallinagomedia 1 Anaspenelope 1254 Limnodromussemipalmatus 9 Anas strepera 92 Limosa limosa 409 Anascrecca 377 Numeniusphaeopus 3 Anasplatyrhynchos 60 Numeniusarquata 8 Anas acuta 2123 Tringa totanus 370 Anasquerquedula 418 Tringastagnatilis 178 Anas clypeata 1311 Tringanebularia 1 Aythyaferina 850 Tringa glareola 2 Aythyafuligula 66 Xenuscinereus 30 Bucephalaclangula 116 Actitishypoleucos 10 Mergusalbellus 2 Arenaria interpres 23 Milvus korchun 1 Phalaropuslobams 255 Circusaeruginos 40 Larus ichthyaetus 812 Circuscyaneus 2 Larusminutus 3038 Circuspygargus 1 Larus ridibundus 1965 Aguila clanga 1 Larus canus 717 Aquila rapax 1 Larus cachinans 736 Falco vespertinus 4 Gelochelidonnilotica 3 Crex crex 2 Sterna caspia 3 Gallinula chloropus 1 Sternahirundo 681 Grusgrus 130 Chlidoniasniger 1667 Fulica atra 155 Chlidoniasleucopterus 8810 Himantopushimantopus 387 Duckssp 3968 Recurvirostraavosetta 802 Calidris sp. 100 Glareola nordmanni 3 Gulls sp. 375

Notes: 1. The tableonly includesthe totalsfrom the 120 point counts; totalnumbers observed of mostspecies were much higher; total estimates in final report; 2. The tabledoes not includenumbers of the delta's Kargatand Chulymriver within Lake Chanyarea; there, for example, 4,000 pairsof Chlidoniasleucoptera were breedingthis year with at least 1,000 Chlidoniasniger; seefinal report.

REFERENCES Danilenko,A.K., Boere,G.C. & Lebedeva,E.A. 1996. Lookingfor the recent breedinggrounds of Slender-billedCurlew: a habitat-basedapproach. Wader StudyGroup Bull. 81:71-78.

Gretton,A. 1991. Conservationof the Slender-billedCurlew. ICBP MonographNo.6. InternationalCouncil for Bird Preservation.159 pp. Cambridge.

Krivenko, V.G. 1991. [Waterbirds and their conservation.]. Moscow,Agropromizdat. 271 pp. (In Russian).