Wader breeding conditions in the Russian tundras in 1996

P. S. Tomkovich & Y. V. Zharikov

Tomkovich, T. S. & Zharikov, Y. V. 1997. Wader breedingconditions in the Russian tundras •n 1996. Wader Study Group Bull. 83:26-36

Tomkovich,P.S. ZoologicalMuseum, Moscow State University,6 BolshayaNikitskaya Street, Moscow, 103009, Zharikov, Y. V. WEGP/ESC, Trent University,Peterborough, Ontario, Canada, K9J 7B8 (Translation)

INTRODUCTION

Followingthe traditional annual reviews of breeding numberswas predictedfor the western sector of the conditions of waders in the Russian tundra, below we Russian Arctic and therefore favourable breeding present observations,impressions and opinions of our conditionsfor birdswere expectedin many regionsas correspondentsregarding situations at certain sites and well. It was difficultto give a forecast for the tundras of regionsof the Arctic in 1996. Let us only remindyou Yakutia due to the overall patchy situation;some sites that from the pictureof distributionand abundance of (the Lena delta) had increasinglemming numbers. A rodentsand Arctic Foxes Alopex lagopus duringthe decrease in rodent numbersand correspondinghigher summer season of 1995 the followingpredictions had clutch depredation rates were expected for Wrangel been made for 1996 (see Materials of the Working Island and the mountaintundras of the upper Anadyr Group on Waders 9: 21-23). An increase in lemming River.

26 INDIVIDUALACCOONTS exceed +12 øC) prevailed in late June and early July. Yu. H. Mineev reported that during the second half of 1. North-westernKola Peninsula. Judging from the summer average daily temperatures were also below different phenologlcal events in the transition zone the mean value from the previous years; the weather betweenthe tundra and forest-tundrathe spring arrived remained rainy and windy, which had an unfavourable there 2-3 weeks later. Continuoussnow cover persisted effect on survival and reproduction of most tundra birds. until late May and active melting of snow began only in Siberian Lemming Lernrnussibiricus numbers remained early June. Practically all of June and beginning of July low although for the first time in 6 years a considerable were characterized by quite cold and rainy weather number of winter feeding sites and "toilets"was found; conditions. Summer snowstorms occurred in mid and at some localities the same was true for the Root Vole '•'^ June. Lemmings were not observed. Microtus oeconornus. Since all Arctic Fox dens found in the area were occupied it was possible to speculate S, A, Dylyuk about an increase in populabon levels. Abundance of the Snowy Owl (did not breed), Arctic Skua and gulls did not differ from 1995, i.e. they were common. Most of the common shorebird species (Red-necked Phalarope Phalaropus Iobatus, Temm•nck's Stint Calidris 2. North-westerncoast of Kanin Peninsula experienced ternrninckii,Little Stint, Ruff, and Dunlin Calidrisalp•na) a late and unusuallycold spring. Phenologicalevents had full clutches early on, later, however, as incubation lagged at least 10 days behind. The seaside sections period progressedtheir size decreased. The Common which are normally free of snow by early May had Ringed Plover Charadriushiaticula and Grey Plover isolated snow-fieldstill July. Throughoutthe wader breedingseason the weather was dominated by windy Pluvialissquatarola were less common than in the and cold conditions and stormy periods;there, however, previous year. By the middle of the second week of July was no snow. Voles were numerous at least locally. the number of Temminck's Stint nests dropped almost There is no information about lemmlng numbers. The two fold apparentlyas a resultof Arctic Skua and Arctic Arctic Fox numbers apparentlywent up since 2 animals Fox activitiesas well as the very cold weather. Hatching were observed in the area where they had not been seen of the Grey Plover chicks was recorded. duringthe previousyear. The Rough-leggedBuzzard Buteo lagopus and large Larids nested successfully. Yu. M. Schadilov, A B. Belousova The abundance of the Arctic Skua Stercoradus parasiticus- the most active wader predator - was rather high. No Snowy Owls Nyctea scandiaca were noted. As far as waders were concerned no deviations from the 4. North eastern part of Gusinaya Zemlya (Yuzhni normal breeding course were observed (even if there Island of the Novaya Zemlya Archipela.qo). was a delay in breeding initiation it could not be Observations undertaken between 19 June and 5 detected) although apparently more clutches and broods September indicated late, cold and snowy spring: on 19 were lost than in the previous year. Population numbers June large thawed patches were noted only at the of common breeding species remained without changes. seaside. The summer turned out to be short, cold and The Ruff Philornachuspugnax was the only exception; extremely rainy o storms were frequent; snowfallswere the specieswas rare duringthe breedingseason and no absent only between 10 July and 23 August. At the flockswere observedin the post-breedingperiod. Little same time the hurricane-force winds not uncommon for Stints Calidrisminuta did not breed (only one individual Novaya Zemlya did not occur. Lemming numbers were was encountered). There is a possibilitythat the Terek low: 1 Collared Dicrostonyxtorquatus and 3 Siberian SandpiperXenus cinereus nested in the area (three Lemmingswere found duringthe season. A 120 square pairs were discovered). km area contained only one Arctic Fox den with 4 pups plus 2-3 single individuals. A Great Skua Stercorarius A. V. Fil'chagov skua pair bred in the area; wandering individuals belongingto the other skua species could be observed almost throughoutthe entire summer. Snowy Owls were uncommon (2-3 individuals/50 square km) and did not breed. The Rough-legged Buzzard density in 3. South-eastern part of Russki Zavorot Peninsula, mountain foothills was low and it is possible that some KhabuikaLake area. The springwas cold and unstable breeding occurred there. The Glaucous Larus weather conditionsprevailed for a long time. Negative hyperboreus and Great Black-backed Gull Larus night and low (+5 øC) day time temperatureswere marinus populationlevels were normal. The following recorded until mid June. Roughly 2% of tundra was shorebirds(in the descendingabundance order) bred in under snow cover until the third week of June; some shallow lakes were still frozen too. The Pechora Mouth the area: Ruddy Turnstone Arenaria interpres, Dunlin, Common Ringed Plover, Kentish Plover Charadrius clearedfrom ice on 21 June. Comparingwith the alexandrinus,Little Stint, and Grey Phalarope previous5 years the start of vegetativeperiod shifted3 weeks back. Cold, with frequent rainstormsand strong Phalaropusfulicarius. Late broodscomprised of pre- fledged young of the Phalarope, Common Ringed Plover winds, weather (average daily temperatures did not

27 and Kentish Plover could be seen until mid August. findingsof nests with hatching young and observations Based on the observations of geese the nest of adult birds displaying distress behaviour allowed us to depredation(mainly by the Arctic Fox) was very strong: suggestthat breedingsuccess of waderswas also high. nearly 80% of the nests were destroyed even though the Breeding of shorebirds occurred almost at usual time number of Barnacle Geese Branta leucopiswas dozens despitethe late meltingof snow: Dunlinyoung hatched of times lower than in 1995. Waders, however, bred on 3 July, Little Stint- 12 July, Temminck's Stint- 17-18 rather successfully. High mortality primarily affected July. Even such a relatively southern breeder as the nests and broods of Ruddy Turnstones and Common Common Snipe Gallinagogallinago nested in the area (a RingedPlovers that nested on open hill crests(by mid brood was found on 26 July). Mixed flocks of waders of July their numberdropped by an order of magnitude); more than 200 individualsappeared in the Yangayakha populationlevels in lowland sections with grassy cover valley on 7-9 August. remained almost unchangecluntil late July. K E. Litvin,Ye. Kh. Gurtovaya V. Kh. Kalyakin

7. Yu,qorskyPeninsula. A lot of snow fell at the end of 5. Southern Gusinaya Zemlya (Yuzhni Island of the the winteraround the Byely Nos Field Station(69036 ' N: NovayaZemlya Archipelago). Thawed patchesand 60013' E): in late May 95% of the groundwas snow- small ponds free of ice were noted in the village of coveredand accordingto a polar researchstation that Byelush'ebetween 4 and 18 of June; however, the was a record snow precipitationyear. The springwas vicinitiesof the village still had a winter-likeappearance late, cold and prolonged. Air temperatures reached the due heavy winter snowfalls. There were two records of average levelstypical for previousyears only in mid the SiberianLemming. Also 1 Rough-leggedBuzzard, 2 June and stayed at that level further on. Storms and Short-eared Owls Asio flarnmeus and transient rains occurredregularly but their frequencyand duration Pomar•neStercorarius pomarinus and Long-tailed were not above the norm. The wader arrival initiated in StercorariusIongicaudus Skuas were observed. Purple early June did not last long. Nesting densitiesof all SandpipersCalidris maritima were common during species were similar to or lower than those of the migration(peak period up to 6 June) and despitethe late previousyear; only in the Ringed Plover the nesting springCommon Ringed Plovers and Dunlinsbegan to densitywent up nearlytwo fold in coastal sectionswith arrive on 5 June, Ruddy Turnstones, Temminck's and suitablehabitat. The nestingperiod was rather spread- Little Stints- 6 June: Ruffs (males) were recordedon 10 out: the differencebetween nesting dates of some pairs and 11 June. The same area experiencedalmost daily of a particularspecies could reach 20 days. snowflurries between 6 and 13 Septemberdespite still Physiologicalcondition of trapped birds indicatedthat no positiveair temperature. Formationof the snow cover clutches were lost owing to the climatic conditions. startedon 14 September. Throughoutthis part of Lemming populationnumbers were low (only 1 Siberian Septemberfew Purple Sandpipersand single Common Lemmingwas foundthroughout June and July). Ringed Ploverswere encountered. Snowy Owls were Territorialpairs of Rough-leggedBuzzards occurredin common (8 individuals/10 km). areas with suitable breeding habitat; as a rule, however, there were no nests (only 1 nest with 1 egg was V. Kh. Kalyakin discovered;it was abandoned3 days later). The only knownArctic Skua pair successfullyfledged their young. There was only 1 Snowy Owl sighting duringthe season. Small flocks of Pomarine Skuas went throughthe area 6. Vai,qachIsland. The winter here was characterized in early to mid June. Arctic Foxes were rather by extremelyhigh precipitation levels while the spring uncommon: early in the summer their were seen almost was late (2 - 3 weeks behindthe usual schedule)and daily; by the end of the season none could be observed prolonged;cold spells•and snowfalls, however, did not in weeks. The following shorebirds bred in the area: occur. Ice on Yangayakha River broke around 20 June. Dunlin, Little Stint, Temminck's Stint, Red-necked The summer climatic conditionswere close to average Phalarope, Ruff, Common Ringed Plover, Ruddy withoutany disruptionsdetrimental for birds. Collared Turnstone, Grey Plover, Dotterel Charadrius morinellus, Lemmingswere not found. The SiberianLemming possiblyCommon Snipe. The overall nest survwalwas numberswere clearly higher than in the previousyear: 57% with the highestlevel observed in the Common they invaded human dwellings and were encountereda Ringed Plover (82%). Generally speakingthat was a number of times in the tundra while in 1995 none were favourableseason for the Common RingedPlover and seen. Arctic Foxesturned out to be rare; there were only an average one for other species. 3-4 sightingsduring the season and a den with litter was found 30 km from the field site. Few Snowy Owls V.V. Gavrilov appeared at the end of June and no breeding was recorded. Of Skuas only the Long-tailedbred in the area. Clutches of Rough-legged Buzzards were of reducedsize (2-3 eggs). Breeding successof goose 8. South-eastern part of Bolshezemelskaya Tundra. pairs under observationwas high. This fact as well as Accordingto a local meteorologicalstation May and

28 early June 40 km to the south from Vorkuta City (67ø17' of Greenshank Tringa nebularia was found as well. A N; 63ø40' E)in Vorkuta River basin were cold although pair of Little Ringed Plovers Charadrius dubius actively the snow was completelygone by 20 May. The air displayingdistraction behaviour was recorded for the temperatureof the second half of June (8.5 øC) did not first time. If broods and adult birds displaying defensive deviate from the norm. Overall the spring was behaviourobserved throughout the first 2/3 of July could somewhat prolonged,the summer temperatures, serve as an indicator, the reproductivesuccess in most however,were approachingaverage values. In July the wader species was high and breedingtook place within amounLof precipitation(rain) was slightly higher than the usual time frame. Clutch and brood mortality the average and there were more days with overcast. attributed to predators and adverse weather conditions Negativetemperatures with snow precipitationwere was close to minimal. recordedthat summer only twice: 15-16 June (down to - 5 øC at night) and 11 July (-5.3 øC). Strong winds (8-10 S. P. Paskhal'ny m/s) were recordedonce (throughoutthe day on 24 June). The rate of growthand phenologyof most shrubstypical for polar willow and tundra-wetland vegetativeassociations of the southerntundra subzone 10. Southern Yamal. By early June the tundra in the did not differ from average values. Accordingto the Shchuch'yaRiver watershed was mostly free of snow observationsconducted on study plots between 5 June which was probably a result of the low total winter and 5 July the Siberian Lemming abundance was precipitationand May thaws. Rivers opened in late May roughlyas low as in the previousyear. Snowy Owls and - first five days of June; there, however, was little Arctic Foxes were not encountered. A pair of Hen flooding. The spring was wet and cold but without long Harriers Circus cyaneu$ and Rough-leggedBuzzards subzerospells. Due to the high amount of precipitation residedin the area but apparently no breedingtook the rivers did not recede until mid June resulting•n place. Only single skuas were seen. The most common almost completelyinundated floodplains. In the Terek tundra wader species included the Golden Plover Sandpiperthis fact determined sporadic distribution,low Pluvialisapricaria and then slightly less numerous breedingdensity and nestingin atypical habitats. The Whimbrel Nurneniu$phaeopus. Three nests of these Common Ringed Plover numbers were extremely low speciesfound in the area successfullyproduced chicks. and its breedingwas almost totally restrictedto Wood Sandpipers Tringa glareola and Common watershed sections. The summer was overall cold and SandpipersActiris hypoleuco$ dominated the river valley rainy - especiallyin August when only 7 days did not and pebble shallows. The overall wader numbers, receive any precipitation. Similar to the spring quick however,were low both in the river valley and tundra. summer floods inundated riparian sections. Heavy Judgingfrom the number of broods observed in late July showers occurreda number of times; they, however did - early August the breeding success could be estimated not appear to have a negative effect on breedingbirds as average. becausethey primarilytook place either duringthe incubationor fiedgingperiods. Populationsof the both D. V. Karelin, D. G Zamolodchikov lemming specieswere on a stage of deep depression: no animals were observed. Trapping data providedby V. G. Shtro for the southern tundra subzone and foothills of the Polar Ural Mountains indicate medium abundance levels for the Northern Redbacked 9. Eastern foothillsof the Ural Mountains(66ø30'-67ø30 ' N). The month of May was rather cold in forest-tundra Clethrionomysglareolus, Narrow-skulled Microtus and southerntundra subzones;it began to warm up only gregalis, and Water Arvicola terrestris Voles. Numbers of the Middendor½s Vole Microtus middendorfi were low. duringthe last third of the month - especially noticeably after 27 May. Ice on the Ob River near Salekhard broke In the forest-tundrapart of the Shchuch'ya River on 31 May- 1 June, i.e. as usually. Plovers, Wood watershed vole numbers were very low; only the Sandpiper,Bar-tailed Godwit Lirnosalapponica, Northern Redbacked Vole abundance could locally reach Whimbrel and Common Snipe arrived on 22 May, the medium level. This situation resulted in generally appearance of the other species occurred between 27 low nestingdensity and minimal breedingsuccess in the and 31 May. Migration along the left bank of the Ob Rough-leggedBuzzard (forest-tundra:most pairs River was not very distinctiveand was practically over desertedtheir nests during incubationand only 2 out of by 5 June. June broughtcool, moderately rainy weather 8 had chicks; tundra: majority of Rough-legged while July was drier and warmer. No climatic anomalies Buzzards did not breed). Only 1 breeding pair of Hen were reported. Rodent populationlevels were extremely Harriers was found in the tundra region; in the forest- low. Only single Rough-leggedBuzzard pairs nested in tundra there were few regular recordsof this raptor. The the area; territorial Hen Harriers and non-breeding Long- distributionof Long-tailedSkua was patchy, most of tailed Skuas were common. The ubiquitousWood them did not breed resortingto a nomadic life-style. In Sandpiperhad the highestnesting density; the Golden skuas 75% of full clutches had only 1 egg. The Arctic Plover, Common Ringed Plover, Bar-tailed Godwit, Skua numbers in the region were quite low but some of Whimbrel, and Ruff were common. There were them still bred. Pomarine Skuas and owls were sighted. The Hooded Crow Corvus corone cornix was rather sporadicsightings of the Grey Phalarope,Temminck's Stint, Common Sandpiper,Common, Pintailed Gallinago uncommonand occurredonly in wooded sectionsof stenura and Jack Lymnocryptesrainlinus Snipes. A pair river valleys. The Arctic Fox is not a typical inhabitantof

29 southerntundras and forest-tundra. Only 1 out of 12 River broke on 25 June, i.e. 5 days later than in 1994. dens surveyedin a 500 square km area was occupied. June was dry while the first three weeks of July were The Red Fox Vulpes vulpes numbers were not high. It rainy although stretchesof dry and warm weather appearedthese animals did not breed in the southern occurred as well. There were no summer snowfalls. tundras but in the forest-tundra zone I den with pups The peak hatchingtime in waders (12-16 July) was was found. Despite seemingly unfavourableconditions associated with a period of cold, windy and foggy waders breeding success was above average or even weather. Collared Lemmings were very common: up to high. This was supportedby numerousobservations of 30 individualswere encountereddaily. This high Wood Sandpipers,Common and Pintailed Snipes, Bar- abundance facilitated successful breeding of Snowy tailed Godwits, Golden Plovers and Whimbrel attending Owls, Rough-leggedBuzzards, Long-tailedand broods. Monitoringof nests of the two latter species (10 Pomarine Skuas. The Brent Geese Branta bernicla nests each) showed that individualnest depredation nested primarily next to birds of prey. No Arctic Foxes rates did not exceed 10%. were seen at the site. Also the Dotterel observed there breeding in 1993 was absent. Breeding densities of V. V. Morozov commonwader specieswere 14 nests/squarekm for the Little Stint and Curlew Sandpiper Calidrisferruginea and 5 nests/square km for the Pacific Golden Plover Pluvialis fulva. The overall nesting density in shoreb•rdswas 11. Southern part of Tazov Peninsula. Arrival of the higherthan in 1994 (35 and 20 nests/squarekm springto the forest-tundraof the lower Pur River (lower respectively). The breedingsuccess was high in all sections of the Hadutte and Tab-Yakha Rivers near the species (70-100%). village of Samburg) was extremely late: accordingto the local inhabitants ice on the Pur River broke on 7 June I. Tulp, L. Bruinzeel, J. Jukema, O. Stepanova near Tarko-Sal and on 15 June near Samburg. The late nature of the springwas confirmed by observations initiatedon 19 June. The Bay of Tazov opened on 26 June. Intensive snow melting occurred at the lower 13. Lower reaches of the Pyasina River apparently sections of the Hadutte and Tab-Yakha Rivers on 23-24 experiencedworse ice and weather conditionsthan the June, tundra lakes became free of ice on 26-27 June. Pur River because ice on the latter broke on 6 July while Buddingof the Dwarf Birch Betula sp. and Alder Alnus the Pyasina Delta was still blocked on 10 July. sp. was recorded only on 25 June, of the Larch Larix sp. - 27-28 June. The weather was hot and dry from late Ya. I. Kokorev June until 12 July (when the field work was terminated). Judging from the mass swarming of Diptera the beginningof the summer fell on the second week of July. Lemmings, voles, Arctic and Red Foxes were not 14. Middle reaches of the Pur River (Western Taimyr). observed. There were no breeding records of the Melting of the snow, spring floods and the other Rough-leggedBuzzard either. Only single observations phenologicalevents were 2.5 - 3 weeks late in the of non-breedingSnowy Owls were made. The Long- typicaltundra subzonewhich resultedin 1.5 - 2 week tailed Skua was a common breeder; the Hen Harrier was delay in breedingof birds. Waterfowl were affected also quite abundant and probably nested in the area. A most stronglybecause their breedingarea - riparian high breeding density was determined for the Wood sections- became free of snow only in late June - early Sandpiper, Temminck's Stint and Bar-tailed Godwit July. Brent Geese bred more southerlythan usually(the (locally, at heavily water-logged tundra sections). Pure southernmost site was located 30 km to the north from tundra sites accommodated breeding Spotted the Pur Field Station). The summer weather conditions RedshanksTringa erythropus,Red-necked Phalaropes, were adequatewithout any climatic anomalies. Early in and Golden Plovers. The wooded river valley yielded the season the abundance of lemmingswas estimated numerous records of the Jack and Pintailed Snipes while as medium; later, by the end of the season, it decrease the Common Snipe was rare. Breeding of the Eurasian perhapsowing to the heavy pressureof rodent- Woodcock Scolopax rusticolawas recorded as well. The specializingpredators. Rough-leggedBuzzards nested Common Ringed Plover was very common on sandy rather densely:6 pairs per 22.2 square km study plot spits along rivers. None of the clutches under and 0.8 - 1.0 pair per 10 km ofthe river course. The observation was lost. SnowyOwl numbersreached 0.5 pair per 10 km of the rivercourse. The HerringGull Larusargentatus which I. P. Pokrovskaya,N. Yu. Obukhova,V. V. bred in colonies as well as singlywas common too. Kamyshenkov Arctic Foxes occupied 15% of dens and the mean numberof pups in a litterwas 8. Wader breeding densitywas lowerthan average,especially so in species nestingin riparianzones. Very few CurlewSandpipers 12. North-westernTaimyr Peninsula. The snowwas were seen. Non-breedingof 4 territorialPeregrine Falco gone relativelylate from the Meduza Bay (20 km south peregrinuspairs was probablyconnected to the overall from Dixon) area so that by 25 June (21 June in 1994) low bird densitiesas was a failed breedingattempt of yet only 50% of the tundra was free. Ice on the Meduza

30 anotherpair. In general,however, the nestingwas were observed. The Dotterel and Pacific Golden Plover successful and survival of broods high. were the most abundant shorebirds in the mountains; in valleys- CurlewSandpipers and LittleStints; on pebble Ya. I. Kokorev beds of mountain streams - Common Ringed Plovers.

M. N. Koroleva,I. N. Pospelov

15. SevernayaZemlya Archipela,qo(Sedov Islands, BolshevikIsland). The springhere was late and the summerquite cold. The averagedaily air temperature 17. South-easternTaimyr. In phenologicalterms this duringthe arrivaland nestingof waderswas lowerthan was the latest spring in three years in the Bludnaya in the previousyears: - 3 øCin June.and - 0.2 øCduring River Mouth (near the village of Novorybnoye):at the the firsttwo thirdsof July. CollaredLetomings were not end of the second third of June a storm covered with found but some traces of their winter activities were snowall thawedopenings. Dunlin- the earliestbreeder discovered. There were no Arctic Foxes either. Only amongstwaders - initiatednesting only at the very end wanderingskuas were encountered;there were no of June while the later breeding species (Pectoral confirmedbreeding records although it is quitepossible SandpiperCalidris rnelanotos, phalaropes, Ruff) did not that some nestingpairs were overlookedon Bolshevik breeduntil early July. Densityof the breedingwaders Island. After migration(9 - 19 June) Purple Sandpipers with low site fidelity(Pectoral Sandpiper, Phalaropes, startedbreeding by late June (eggs in one nest hatched Ruff)was lowerthan in the considerablyearlier season on 20 July). Thereforeit can be concludedthat of 1995 but higherthan duringthe only slightlyearlier unfavourable weather conditions did not cause a delay summer of 1994. The summer was relativelywarm and in the arrival and breedingtime of this species. A dry, no snowfell duringthe breedingseason. Letomings slightlylower abundance of breedingbirds is, however, (90% Siberianand 10% Collared) had the highest possible. It is highlylikely that the late springon Taimyr densityin three years. Afterthe abundancepeak during was the reason behind the accidental records of the the snow melting in late June - early July they were Red-necked Stint Calidrisruficollis (in a flock of Purple beingencountered by each observerfor up to several Sandpipers)on DomashniIsland on 15 June and two times per day throughoutthe monthof July. For the first RuddyTurnstones between 22 June and 31 July. time in three year a pair of Arctic and 3 pairs of Pomarine Skuas nested in the area. Few Snowy Owls A. E. Volkov showedup at the end of the season. Only few isolated Rough-leggedBuzzard pairs nested in the area as well as Long-tailedSkuas whose breedingdensity was low - the same as in the previousyears. No Arctic Foxes were observedduring the wader reproductiveperiod 16. Byrran.qaMountains near the Levinson-Lessing what determinedthe highestbreeding success in the Lake (74030' N; 98030' E). Comparing to the previous birdsin three years:reproductive success was 66 to year the springwas 10 days late. Negative 89% in all commonwader species. The main reasonfor temperatures(- 3 øC)and frequentsnowstorms occurred clutch mortality - quite unique for this season - was until20 June. Despitethese conditions,however, the tramplingof eggs by the ReindeerRangifer tarandus, snowwas almost gone by the thirdthird of June. After which lingeredin the studyarea until late July (a month their arrival most birds concentrated at small snow-free later than normally). Overall it can be statedthat the patchesalong the KrasnayaRiver course but after 20 waders breedingin the region had the highestsuccess June their densitiesin riparian habitatsdropped in three years. considerablyand paired individualsbecame prominent. The summer was cool but without snowstorms. The end M. Yu. Solov'ev, V. V. Golovnyuk, M. N. Dementiev, of July and earlyAugust experienced heavy rains. The T. A. Pronin, T. V. Sviridova Siberian Letoming density throughoutthe summer remainedat 2 individualsper 100 trap-days. Densityof the Collared Letoming in different habitats of the KrasnayaRiver valley was relativelyhigh (6 individuals per 100 trap-days).Their numbers showed an upward 18. Lena Delta. Springand early summer climatic trend startingthe third third of July but by late summer conditionsin the area were extremely unfavourablefor the CollaredLetoming abundance gradually decreased shorebirds.The meteorologicalservice of the village of to 2 individualsper 100 trap-days. Juvenileindividuals had no records of such a late and cold spring since did not breed. Arctic Foxes were fairly uncommonin the 1932 - the year of its foundation. Migrationin the mountains: 3 dens were found in a 400 square km area southernpart of the deltawas onlyslightly behind the of whichonly 1 was inhabited.The diet of that family usual schedule. However, the continuous snow cover was dominatedby SiberianLetomings and hare Lupus on tundraand frequentsnowfalls forced waders to- sp. The breedingdensity of Long-tailedand Arctic concentrateat few thawed patchesalong channel banks Skuas was rather high. A 100 square km area and tributarymouths. Speciescharacteristic for forest- contained1 breedingPeregrine pair, 6 non-breeding tundra and southerntundra could be found together with Rough-leggedBuzzard pairs and 1 Rough-legged highArctic birds, often in atypicalhabitat zones. The Buzzardnest with a clutchof 2 eggs. No SnowyOwls lichenlayer at suchsites was literallyturned upside-

31 down by foragingbirds. Even the food garbage discardedby humans was consumed. The first two thirds of June witnessed mass mortality of Ruddy 19. In the Delta and vicinities of the villa.qeof Turnstones,Red-necked Phalaropes, Curlew Yukaqir arrival of the spring took place approximately15 Sandpipers,Little Stints, Red-necked Stints, and - 20 days behindthe average time (observationsfrom a Temminck's Stints caused by emaciation. A stable number of previous years). According to a local crossingof mean daily temperatures above the zero meteorologicalstation the month of June was coldestin mark and subsequentmelting of snow occurredonly on more than twenty years. Inhabitantsof the settlements 20 June. On the same day active courtshipdisplays of Ust-Yansk and Kresty reported mass mortalityof began in most species includingthe Grey Plover, Pacific small sandpipersand passerine birds around 12 - 15 Golden Plover, Ruddy Turnstone, Common Ringed June when a return of subzero temperature was Plover, Red-neckedand Grey Phalaropes, Ruff, Curlew observed. Hundreds of birds that had arrived to the Sandpiper, Dunlin, Sanderling Calidrisalba, Little Stint, tundra only a few days before congregatedon the Yana Red-neckedStint, Temminck's Stint, Long-billed banks and in the settlements. In Nizhneyanskwinter Dowitcher Limnodromusscolopaceus as well as nest conditionspersisted until 15 June while •n Yukagir until buildingin Dunlin. Essentiallythe entire breeding 20 June when snow was still covering up to 80% of season was shifted two weeks back and the number of tundra. Ice on Yana broke only on 17 June. A few days nestingwaders was quite low. Some species probably beforethat momentthe risingwater broke though did not breed at all. The were no climatic anomalies certain segments of banks and flooded the adjacent low observedin the delta in July, the month, however,was tundra sections. By 23-25 June the outer delta (in a 20 - overallmuch colderthan usually. Spring floodsdid not 30 km belt) was 70-80% flooded. After an abrupt drop affect breeding as they occurred before the start of in the water level which occurred over a period of 1 day nestingand the water levels were not too high. the active egg-layingbegan. Very few clutcheswere laid Lemming numbers reached their peak and both winter prior to the floods and most of them were probably and summer breedingin these animals was successful. destroyed. Water levels in the delta channels remained Snowy Owls and Arctic Foxes were numerous and high until mid July, thus most delta islands were ubiquitousin the delta. Pomarine Skuas bred in its submerged strongly limiting nesting opportunitiesfor northernpart. Rough-leggedBuzzards were pushed by waders and other birds. Near Yukagir first eggswere the Owls slightlyto the south from their usual laid on average 1 week later than normally. In July- distributionarea. Peregrinesprobably did not breed due August the weather was rather unstable, more often cool to low shorebirdnumbers (the only investigatednest with low amount of precipitationbut overall favourable which had been occupiedfor a number of years was for breeding birds. empty althoughthe adult birds were seen nearby). Breedingsuccess of waders in the delta was very low. Distributionof microtine rodents was quite uneven. The negativeeffect of climatic conditionsduring the pre- Average vole numberswere recorded near the village of breedingperiod canceled out the advantage of the high Kazach'e. Sixty percent of animals trapped by S. lemming populationlevels. Grigor'ev were Root Voles, while the rest - Northern Red-backedVoles. The Siberian Lemming and Northern V. I. Pozdnyakov Red-backedVole numberswere low along the Samandon channel in Tastakh area. The highest 18. In the Lena Delta the unusuallycold springwas species diversity (the actual numbers, however, were neverthelessfollowed by the usual appearanceof open low) was found near Nizhneyanskwhere the high tundra water and the breakingof ice. Wader arrival to the was dominated by the Siberian Lemming (60%) and the centraldelta was facilitatedby the availabilityof open NorthernRed-backed Vole (35%) while only single water and was premature:during the first half of June individualsof the Collared Lemmingwere encountered. adult mortalitywas very high due to the absence of food The Narrow-skulledVole Microtusgregalis was locally and extremelylow temperatures. There were few quite common near human dwellings. Accordingto the wadersin the northernpart of the delta and they arrived local inhabitantsnumbers of lemmings r•ear rather late. Peak lemming numbers resulted in a Nizhneyansk were high in March-April when the animals successfulbreeding season for Snowy Owls, Pomarine were seen around their winter burrows and in tundra Skuas and Rough-leggedBuzzards. Grey Plovers, Little (this was supported by plentiful signs of their winter Stintsand Grey Phalaropesalso had a goodyear even activitiesin the outer part of the delta). We found only thoughtheir nestingstarted 2 weeks later. No other few rodentskilled by the flooding. The general wader species nested in the northern part of the delta impressionwas that either the small winter peak that year. The summer and autumn temperatureswere occurredbefore the arrival of the spring or the growing low as well and ice formation began 7 - 10 day earlier numbers of rodentswere undercut by the heavy spring than usually. Amongst the unusual autumn events was floods. the appearanceof numerousflock of juvenile Ruffs in the northernparts of the delta (previouslysuch a The predatorpressure on bird clutchesin the lowerYana phenomenonwas recorded on the New Siberian was also uneven. The abundance of Arctic Foxes was Islands). mediumto high in the north-easternpart of the delta where 2 inhabited dens were located in the coastal zone D. V. Solov'eva - outsidethe range of the floods;they had a minimumof 6 and 4 pups;another family with 2 youngwas seen in

32 the tundra. It is presumed that some young as well as were observed, Northern Pikas Ochotona hyperborea adult animals were a subject to mortality. The were, however,locally common. An adult Root Vole and informationon the high Arctic Fox abundance was also a juvenile individualof an identifiedspecies were corroboratedby hunterswho used leg-holdtraps during trapped near the settlement of Ust-Kuyga during the the winter. Southerly, down to forest-tundra, at flooding. Tundras around Kular had low rodent Samandon neitherArctic Foxes nor any signs of their abundance:their bones were found in Rough-legged activities were seen. Red Foxes were not uncommon at Buzzard pellets,one individualkilled by a Raven Corvus the middle flow of the Ilin Shar channel. Some locations corax was investigated. Two Root Voles were seen in housedsingle Long-tailedand Arctic Skua nests. Only the forest-tundra near the settlement of Severnoye. few Rough-legged Buzzards and Snowy Owls were Infrequentsigns of lemming activitieswere noted in the observedalthough judging from the locally gathered tundra as well. In the Kular Chain area and adjacent informationin so'meyears they are quite common. regionsthe predatorpressure on bird clutcheswas apparentlyquite moderate. No evidenceof depredation Bird nests located in the outer part of the delta (the was found along the PoluosnyRidge duringthe spring. typical tundra subzone) especially in its western sector fared the worst from predation by the Arctic Fox and E. E. Syroechkovski,Jr., S. V. Volkov, C. Zockler, M sl

33 apparentlythe breeding success in birdswas satisfactory. 22. Indi.qirkaDelta. The snow melted by 26-27 June. Only Red-neckedPhalaropes were noted breedingin the S. I. Mochalov area in late June. Few Common Snipes, Ruffs, Grey Plovers and Pectoral Sandpipers were observed as well.

A. G. Dyagterev, N. N. Yegorov, S. M. Sleptsoy 25. Cape Schmidt area. According to the observations conductedin late June - early July the summer on the northernChukotka coast was cold despite a presumably early spring or little snow accumulation over the winter. 23. Lower Chukoch'ya River. The spring at the Kolyma No lemmings were observed but there were medium lowlandwas extremely cold and prolonged,ice on the populationdensity levels of the Root Vole at Cape Chukoch'ya River broke only on 26 June. At the same Ryrkarpiwhere a pair of the Rough-leggedBuzzard time even the shoreline strip did not thaw at many nested. Breeding of Long-tailed and Arctic Skuas was tundra (elevated) lakes. The air temperature did not noted in the tundra. Only single Arctic Foxes were exceed +3øC before the ice breaking. Cloggingof the observed and no breeding was recorded. Of some river flow with ice resulted in flooding of a large section interest are observations of breeding Red-necked Stints of the valley which destroyed some nests of ducks, (a nest was found) and Ruff (downy chicks) as well as swans and waders. After a weak peak in numbers in sightingsof the Dotterel and Spotted Redshank. 1995 lemming populations levels were in decline. One hundredtrap-days yielded only 6 animals. Arctic Foxes I. V. Dorogoy and Rough-legged Buzzards bred successfully;at only 1 den out of 5 the pups were abandoned being 1 month of age. There were 4 chicks in each of 4 Rough-legged Buzzard nests found in the area (hatching periodwas 26. Belyanka Spit in the northern part of 25-30 June). No Snowy Owls nested at the site and KolyuchinskayaBay experienced a cold summer (late only single individuals were observed. All signs June observations):the weather was dominated by cold indicatedthat for shorebirdsthe breeding season was winds with snow flurries, the sea along the north shore successful. Nests of the Little Stint, Pectoral Sandpiper was cloggedwith masses of broken ice. Lemmings and both Phalaropeswere found quite commonly. Few were absent but some Root Voles kept near the hut. nests of the Grey Plover and Temminck's Stint were Only single pairs of the Arctic Skua nested in the area. located. These nests (1 of each species) were An abandoned Raven nest on a navigationtower was depredatedbefore clutch completion. The Ross's Gull investigated. Few dozen Pomarine Skuas occurred Rhodostethiarosea did not breed. Geese were thought close to the shore where they attacked kittiwakesthat to be breedingsuccessfully. One of the 3 discovered were catching fish in the windows of open water Bean Goose Anser fabalis clutches hatched on 30 June; amongst ice floes. Arctic Foxes did not breed. 2 of out 6 Bewick'sSwan Cygnus columbianusnests Commonly breeding wader species includedthe Spoon- were flooded. billed Sandpiper Eurynorhynchuspygrneus, Dunlin, Western Sandpiper Calidrisrnauri and Red-necked A. V. Kondrat'ev, A. N. Lazutkin Phalarope while the Rock Sandpiper Calidrisptilocnernis and Ruff were rare.

I. V. Dorogoy 24. Lower Kolyma River. In the summer the weather was rather unstable. It was cold for most of the time and only 2-3 days each month were warm with temperaturesof up to +25øC. Snowfalls occurredevery 27. Wrangel Island. Accordingto observationsof 24-26 month and in August they became not uncommon. First June the snow melted relatively early but the summer shorebirdsarrived in late May. Only Grey and Red- was cold with sporadic snowstorms. Both lemming necked Phalaropes and the Temminck's Stints were speciespopulations were in deep depression. From numerouswhile numbersof the Wood Sandpiper, predatorybirds only the Long-tailedSkua nestedin the Common Sandpiper, Common and Pintailed Snipes area. Single Snowy Owl males were also observed. decreased noticeably. Great Knots Calidristenuirostris Arctic Foxes were uncommon and did not breed. The nested in the usual areas at the lower Omolon River followingcommon wader species were recorded' in the where the Little Whimbrel Nurnenius rninutus was area (in the descendingabundance order): the Ruddy observed as well. At the beginning of the last third of Turnstone,Grey Plover, Dunlin, Red Knot Calidris June at the Chukoch'ya River mouth most wader canutus. The Red Knot abundance was lower than in clutcheswere still incomplete. In late June high the previousyears. predationrates by Herring and Glaucous Gulls on clutchesof both Phalarope speciesand the Temminck's I. V. Dorogoy Stiqt were recorded. Despite the cold summer

34 water levels at some rivers (Schuch'ya on Yamal, Yana in Yakutia) for a long time prevented shorebirdsfrom 27. Wran.qelIsland. The snow melted relatively late in breeding in riparian zones. the season and until the third week of July the weather remained cool with frequent precipitationand fogs. In most areas the cold spring was followed by a cold Augustwas the warmest month during which the and wet summer. Only at some sites (Yugorski weather was mostly clear and calm (same was true for Peninsula, near Salekhard on Ob, southern Tazov the first half of September). No snow fell in the summer. Peninsula, southernmost sites of Taimyr and Wrangel The abundance of both lemming species was at its Island (from late July)) the summer was normal or even lowestthroughout the island: 1 Collared Lemming was warmer than usually. Despite the seemingly caught per 300 trap-days and 1 Siberian Lemming was unfavourable for birds general summer conditions most trappedas a resultof a full survey of a 4 ha area. regions did not experienceany climatic disturbancesof Letomingor traces of their activitieswere primarily catastrophic magnitude; summer snowfalls were found in settlementsor near field stations. Snowy Owls registeredonly in 6 areas: Kola Peninsula, and Pomarine Skuas did not nest and their numbers Bolshezemelskayatundra, lower Indigirka and Kolyma. were below the normal level. Only one breeding attempt Chukotka and Wrangel Island. This is the exact reason was recorded in the already depressed Arctic Fox why the cool summer conditionshad a weak effect on population(a den with a litter that died from starvation breedingsuccess of waders which are generally adapted was found). Breedingsuccess of common wader to severe conditions. There were some groundsto specieswas relativelyhigh. Nesting densitiesdid not presume brood mortality only in north-easternYakutia differ from other years. At the end of July numerous due to snow precipitation. Red Knot, Ruddy Turnstone, Grey Plover and Dunlin broodscould be observed. Few Pectoral Sandpiper and In 1995 some sites still boasted high lemm•ng Grey Phalarope and 2 Red-necked Stint broodswere populationnumbers - in Yakutia first of all; a tendency seen. towards an increased in these rodent numbers became apparent in centralTaimyr and the Lena Delta. In 1996 M. S. Stishov these again were Taimyr and the Lena Delta were lemmings appeared to be common or perhaps even abundant. In the Yana Delta high numbers observed in the spring decreased as the summer progressed;it is The total number of sites from which information was also possiblethat numbers were droppingalong the obtainedin 1996 droppedcontinuing the generaltrend Chukoch'ya River in the summer as well. At all other attributedto the financial and logistical difficulties sites lemmings were either absent or rare. Only two associatedwith visitation of remotes regions of the sites (both in the European part of Russia) produced country;in particularseveral permanentfield stations increasingpopulation levels includingRusski Zavorot were shut down including those on Yamal and Taimyr. Peninsula near the Pechora Delta and Vaigach Island. This year no information was received from northern Voles were locally common on Kanin Peninsula while at Yamal, Gydan, northern Taimyr (east from Dixon) and all other sites their populationlevels were not above the southern Chukotka Peninsula. average.

In some regionsthe spring arrived relativelyearly As always the distributionand partiallyabundance of (southern Yamal, sources of the left Indigirka tributaries Arctic Foxes directlydepended on the rodentabundance and apparently the north Chukotka Peninsula coast), - that of lemmings in particular. Therefore it does not later return of cold weather, however, resulted in come as a surprisethat all dens in the Pechora Delta ,qenerallycold sprin,qand cool, wet summer almost were occupiedand breedingat several Taimyr sites, in throughoutthe Russian Arctic. Only in 2 areas - the the Lena Delta, maritime section of the Yana Delta and south-easternBolshezemelskaya tundra and southern on Chukoch'yawas successful. Single and not always Yamal Peninsulathe spring phenologicalevents successfulbreeding attempts were reportedfrom occurredwithin the usual time frame. Reports from Novaya Zemlya, Vaigach, southernYamal and Wrangel almost all other regions indicatedsnow melting, opening Island. Increase in the Arctic Fox numbers relatively to of water bodies and the other spring events as being the previousyear was recorded in the European part of from several days to 3 weeks late. Central northern the Russian tundras - Kanin and Russki Zavorot Yakutia experiencedextremely snowy and cold spring Peninsulas. which resultedin incidentsof wader mortality (quite massive in the Lena and Yana Deltas) when the birds Breedingof birds specializingin preying on rodents- the arrived to breed at usual time. In most cases the late Snowy Owl and Pomarine Skua - took place only on springled to a delay (sometimesup to 2 weeks) in Taimyr and in the Lena Delta, i.e. where letoming breedingseason initiation. The unusuallyhigh spring numberswere considerablyhigh. Nobody reported floods on the Yana River were not detrimental to the breedingShort-eared Owls. Rough-leggedBuzzards reproductiveefforts of waders becauseof its timing nested in many areas althoughnot always successfully while we suspectthat the same kind of occurrence but their numberswere high only on western Taimyr destroyedmany cluthcesalong the Chukoch'yaRiver in Peninsula. eastern Yakutia. At the same time persistence of high

35 Snow and weather conditions early in the season undoubtedlyaffected not only the dates of the start of bird breeding but also their distributionand in some cases abundance. It is believed that this can explain the absence in the Little Stint on Kanin Peninsula, observationsof displaying Sanderlings in the Lena Delta and unusualsightings on Novaya Zemlya. It is believed that some wader species also did not breed in the Lena and Indigirka Deltas.

Wader breedinq success was below averaqe in the European part between the White Sea and Pechora River where the Arctic Fox numbers went up. Easterly up to Taimyr inclusivelyreproductive success rates were Rood or even hiqh; whenever exact numbers were available, they exceeded 50%. Farther to the east, in Yakutia the situation was not so clear. Field researchers indicate poor reproductivesuccess and provide information about high rates of clutch loss in the Lena Delta (despitethe high lemming numbers), Yana Delta, lower Indigirka and Kolyma. It is possible that in the latter two regionsclutches were lost due to poor weather conditions. At the same time birds nested quite successfullyjust slightly farther to the south - in the mountains around the lower Yana and Indigirka and probably Chukoch'ya. The outcome of the breedinq season on Wranqel Island should be considered successfulas well (despite the absence of lemmings).

Consideringthe three-year cycles of lemming numbers in Western Siberia and Taimyr it may be expected that growth of the rodent numbersthat was witnessedon Taimyr in 1996 will spread westwards to Yamal during the followingyear (except for the southern parts of the peninsula) and perhaps even farther if conditionsare optimal - all the way to the White Sea. On Taimyr itself (some areas) lemming numbers will probably continue increasingreaching the peak by the summer of 1997 (for example in the Arctic tundras north from the Byrranga Mountains)while some other regions (near Dixon for instance) will experience a summer decline. In Yakutia the depressionshould start in the Lena and Yana Deltas and on Chukoch'ya River while some increase may be expected for Indigirka

In summary therefore one should expect to see a weaker predatorpressure on clutches and broods of tundra birds in northernparts of Eastern Europe and Western Siberia; the impact by Arctic Foxes and other predators on breedingbirds will most likely increase on Taimyr and in the tundras of Yakutia. In general then, provided the weather does not complicatethe picture,the summer of 1997 will most probably be successfulfor the tundra birds overwinterinqin Europe and Africa and will be poor for northern Yakutia breeders wintering in Asia, Australia and America. The fragmented nature of information available for Chukotka does not allow us to make any specific predictionsfor the region.

P.S. Tomkovich

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