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Home , Skua, Tundra vole, Vaygach Island

Breeding conditions for in the of in 1991

Vadim K. Ryabitsev (ed.) (translatedby JadwigaGromadzka)

Ryabitsev,V.Ko 1993. Breedingconditions for waders in the tundrasof Russiain 1991. Study GroupBull. 71: 20-25. Most observersworking in tundrahabitats in 1991 hadthe impressionthat in differentregions between the White Sea and the Anadyr Plateau the breedingsuccess of waders in 1991 was moderateor high. The prognosismade in 1990 that the 1991 breedingseason would be successfulfor waders, appearedto be correctfor the greater part of the Eurasiatictundra. Only in the Western Taymyr, where the numberof lemmingshad startedto decrease, and in southernYamal, in placeswith low lemmingabundance, was birdbreeding success unexpectedlylow. More detailedstudies carried out in northernand centralYamal and in northernTaymyr confirmed these impressions.Though the densityof lemmingswas not maximalin all places,their numberswere great enoughto attractmammal and avianpredators. This gave the possibilityof higherbreeding success for waders and other small . Low breedingsuccess of waders, besidesthe WesternTaymyr, was noted only in coastalhabitats of the Murmanskregion, and locallyin Yakutia and Chukotka. Ryabitsev,V.K., Instituteof Plant and AnimalEcology, Ural Science Centre, RussianAcademy of Science, 8 March Street 202, 620008 Sverdlosk, Russia.

This is the fourthpaper describing the breedingconditions especiallyautumn migration was observedmuch later for waders in the Russian tundras, the source of most than usual. Additionally,the autumnmigration of many waders migratingthrough/to Europe and Africa. In the specieswas unusuallyprolonged, though its intensitywas first such review,covering the 1988 breedingseason at average levels,and higherthan in previousyear. Not ( WaderStudy Group Bull. 57:40-41 ), it was possibleto many waders bred. Their breedingwas successfuland gather data from 13 sites. Every year since then, the absenceof rain duringthe periodof chick growth however, the information seems to become more additionallycreated favourable conditions. complete,with the numberof sites includedbecoming /. P. Tatarinkova higherand higher( WaderStudy GroupBull. 64:51-54; 67: 57-62). For 1991 it has been possibleto gatherdeta- ilsfor 25 sites. As for previousreviews, each of the 2. KOLA PENINSULA- MURMANSK COAST followingnumbered sections refers to an area shownon the map (Figure 1), and the name(s) of the relevant Springwas late and prolongedcool weather with informantsare given at the end of each section. periodicaldroughts predominated during summer. The abundanceof the NorwegianLemming L. lemmuswas Some terms describingdifferent types of habitats very low (they were met only occasionallyat the beginning are used. Four maintypes are mentioned,distributed of August). zonallyfrom the southto the north,and called: southern Yu. V. Krasnov tundra (= shrubtundra), typical tundra (= moss-lichen tundra),arctic tundra (withpatches of bare soil and mostly vascularplants) and polar desert (Chernov1985. The KANINPENINSULA- WESTERN COAST (VICINITY OF liv/ngtundra. Cambridge). SHOYNA) Duringsummer 1990 the growingabundance of was noted in some regions. Fromthese observationsit Snow cover melted earlier than usual, althoughother was predictedthat the 1991 breedingseason would be seasonalphenology was normal. In mid-Junestrong very good for waders all over the vast Palaearctictundras winds occurred. Signs of lemmingactivity (marks, tracks, (Wader StudyGroup Bu//. 67: 57-62), These predictions traces) were not discovered. were very numerous are comparedagainst the real situationbelow. in willowthickets. Rough-legged Buzzard Buteo lagopus and Nyctea scandiacabred. Those waders common in the area occurred more numerouslythan in 1990: Temminck's Stint Calidris temminck/i,Dunlin C. 1. WESTERN MURMANSK REGION- AYNOVY ISLANDS alpina, Ph/Iomachuspugnax, Red-necked Phalarope PhalaropusIobatus and some others. Waders bred at Springstarted early. In April, snow cover had already usualtimes and their nestswere predatedmoderately disappearedalmost completely from islandsand the (mainlyby the ArcticSkua Stercorariusparas/t/cus). mainlandcoast. At the beginningof May, however,the Winter hunting(1990/91) for the ArcticFox Alopex weather changedfor the coolerand the temperaturewas lagopuswas extremelysuccessful. relativelylow duringthe whole summer. Springand V. V. Leonovich& A. V. F/Ichagov

2O WESTERN BOL'SHEZEMEL'SKAYATUNDRA- BASIN 7. VAYGACH ISLAND OF THE LAYA & SHAPKINA RIVERS Springwas as usual,the summercool with muchmist. In Springwas early and warm; summerprolonged and rainy. the northernpart of the Island,in arctictundra habitats, The abundanceof Siberian LemmingLemrnus sibiricus densitiesof letomingsand Arctic Foxes were low. was moderate,it was highfor Ruddy Clethrionomys Amongstbirds of prey only Rough-leggedBuzzards were rut#us and maximal for Narrow-sculled Vole breeding,but at low density. Breedingof waders and grega/is. Rough-leggedBuzzard and Long-tailedSkua geese was as normaland breedingsuccess was high. $tercorarius/ongicaudusbred successfully.Breeding successof the WillowGrouse L. lagopuswas extremely In the centralpart of the island,the numberof lemmings high;that of waders seemed to be high also. was maximaland in southernpart their abundancewas A. N. Petroy higherthan on average, but not yet maximal.Arctic Foxes reproducedvery successfully(8-12 puppiesper pair)ø Predatorsin that part of the islandbred numerously, 5. EASTERN BOL'SHEZEMEL'SKAYATUNDRA mainlyRough-legged Buzzard, Snowy Owl and Pomarine Skua. Breedingsuccess of wadersand geese was high. V. V. Morozov Withinsouthern and typicaltundras spring was exceptionallyhot and quick:on 23 May air temperature exceeded20øC and it was the same up to the end of June. The ice on riversbroke-up on 26-31 May, all 8. NORTHERNYAMAL - STATION "YAYBARI" (71ø 04' N) seasonalphenology took place c. one monthearlier (!) than usual. Summer was cool and wet with summer- Springwas very early. The ice broke-upon 5-8 June. floods,especially intensive in mid-July.Within typical Snowcover meltedalmost completely within the first 10 tundrasand in northernpart of southerntundras the days of June. Summerwas moderatelywarm, without numberof both lemmingspecies (Siberian and longperiods of strongcoolness. SiberianLetomings CollaredLemming Dicrostonyx torquatus) and Narrow- reproducedvery numerouslyand successfullyduring sculledVole was maximal. In the southernpart of the summer. Amongstraptors only PomarineSkuas were southerntundras, the abundanceof Siberian Letomings breed at high density(2.4 pairs/kin2) but their pressureon was high,it was maximalfor Narrow-sculledand Ruddy waders was not marked because of the fair densityof Voles, and it was also highfor some other small . Foxes bred successfully,but they were not (Short-tailedVole Microtusagrestis, Ground Vole numerous. Of 17 nests of Grey Plover Pluvialis terrestrisand ArcticShrew Sorex arcticus). The densityof squatarola,16 hatchedchicks (the female from 17th nest ArcticFoxes was high in the northernpart of the area and was caughtby a PeregrineFalco peregrinus). Nesting low in the south. SnowyOwl, Rough-leggedBuzzard, successof Dunlinwas 89% (of 18 nests)and in LittleStint Hen Harrier Circuscyaneus and skuasbred numerously - 83% (of 24 nests). Generalwader incubationsuccess and successfully. was estimatedas 82%. Duringthe time of tendingchicks, conditionsappeared favourable and mostchicks fledged. In the lower Kara river area (east side, in the northto 68 ø V. K. Ryabitsev& K. V. Ryabitsev 50'N and in the east to the BaydaratskBay of the ), the densityof lemmingswas moderateand Narrow- sculledVole densitywas maximal. Arctic Foxes were not 9. CENTRALYAMAL - STATION "KHANOVEY" (68ø 40' N) numerous.Rough-legged Buzzards bred numerously, althoughSnowy Owl did not breed numerouslyand had Springwas very early,the summercool but withoutvery low breedingsuccess. PomarineSkuas Stercorarius cold periodsand heavy rains. Breedingdensity of most pomarinusdid not breed. Generally,in the whole region, waderspecies was a littlehigher than average. The wader breedingsuccess was higherthan average. densityof Red-neckedPhalarope was twice as highas the V. V. Morozov previousyear (32.5 pairs/km2).The densityof the Ruff was relativelyhigh (15 nests/kin2).Little Stints did not occur.The densityof letomings,especially of the Siberian 6. YUGORSKIY PENINSULA Lemming,increased in comparisonwith their numberin previousyear and was estimatedas moderate. Amongst In northernpart of the Peninsulaspring was a littleearlier raptorsonly Rough-leggedBuzzards were fairly numerous than usuallyand in the south it was clearly earlier and (0.54 pairs/kin2):the densityof Long-tailedSkuas and warm. Summerwas cool and rainy,with strongfloods. ArcticSkuas was muchlower (0.04 pairs/kin2 and 0.09 Densitiesof both letomingspecies and Narrow-sculled pairs/km2 respectively).Snowy Owls did not occur. Vole were maximal. ArcticFoxes were very numerous:all Breedingsuccess of waderswas not high,most probably dens were occupiedand litterswere large:9-13 puppies becauseof the activityof non-breedingskuas. Fourteen per pair. Breedingsuccess of predatorswas very high: nests of Ruff (of 22 found), 7 nests of Red-necked morethan 60% of PomarineSkuas raisedtwo nestlings, Phalarope(of 15 found)and two nestsof Wood Sandpiper SnowyOwls had 5-9 nestlingsper pair, and Rough-legged Tringag/areo/a (of 5 found)were destroyedby skuas. Buzzardshad 3-6 nestlings. Breedingsuccess of all They,together with Rough-leggedBuzzards, reduced the waderspecies was high. numberof wader chicksquite considerably. V. V. Morozov N. S. Alekseeva,Eo A. Polents& Yu.A. Tyull

21 10. SOUTHERN YAMAL- BASIN OFTHE PRAVYI 12. TAZOVSKIY PENINSULA YURIBEY in the area of the confluenceof the Poylova-Yakhaand Springwas early and as a resultthe arrivaland breeding Ngarka-Khorvutarivers (southern tundras) the timingof of manybirds took place about two weeksearlier than ice break-upon riversdid not differfrom the long-term usual. No extreme weather changes duringthe breeding average. Summerwas hot and dry. From visual season were noticed. The abundance of rodents estimation, the abundance of both Siberian and Collared' increaseda little. The proportionof occupieddens by Lemmingswere high. Rough-leggedBuzzard, Peregrine, ArcticFoxes increased to 20%-30%. Rough-legged Long-tailedSkua, ArcticSkua and Snowy Owl bred Buzzardbred in high density,Long-tailed Skua and Arctic successfully.Terek Sandpiperand Temminck's Stint were Skua Stercorariusparasiticus were common,and the numerouson breeding sites close to rivers, Red-necked Snowy Owl was met only locally. Golden Plover Pluvialis Phalaropewas numerousin morewet tundrahabitats; apricaria,Pacific Golden PloverPo fulva, Grey Ploverand GoldenPlover, Ringed Plover, Wood Sandpiper, Ruff, Ringed Plover Charadriushiaticula bred successfully. CommonSnipe G. gallinagoand PintailSnipe G. stenura S. P. Paskhal'ny were common. Grey Plover,Spotted Redshank Tringa erythropus,Whimbrel and Bar-tailedGodwit occurred rarely. Generallythe breedingsuccess of waderswas 11. SOUTHERN YAMAL- MIDDLE SHCHUCH'YA RIVER high. V. A. Yudkin & V. G. Kozin Springwas the earliestof the last 18 years:ice on rivers disappearedin mid-May,and snow in tundra melted completelyup to mid-June.Summer was prolongedand 13. IVlAIVlONTAPENINSULA rainy. The densityof Narrow-sculledVole was very high, and of RuddyVole and lemmingsit was fairlyhigh. Long- In the arctictundra lemming abundance was highand tailed Skua, Snowy Owl and Rough-leggedBuzzard bred ArcticFoxes bred. SnowyOwls had big clutches(8-9 numerously.The proportionof birdsin the diet of Rough- eggs);close to owls Brent Geese Brantabernic/a bred, leggedBuzzard (according to pelletanalysis) was and it is probablethat also Red-breastedGeese Branta considerable.Along the river,Common Sandpiper Actitis ruffcol/isbred also. Skuas and Rough-leggedBuzzards hypo/eucoswas more numerousthan normaland the were breeding. Breedingsuccess of waders seemed to Terek SandpiperXenus cinereuswas quiteabundant. be high. Amongstwaders breedingin the tundra, Ruffswere V. S. Zhukov & D. I. Ivanov absent and the abundance of other waders was lower than usual. They occurredpatchily (particularly Whimbrel Numen/usphaeopus and Bar-tailedGodwit Limosa 14. THE TAYMYR /apponica). S. A. Mechnikova in the western part of the Taymyr arctictundras, at the end of winter,the abundanceof lemmingswas noted as maximal. Beforedispersal to new areas they startedto

Figure 1. Localitiesmention in the text.

22 die. In typicaltundras their abundance persisted at earlier than in 1990, as a result of thinner snow-.cover. relativelyhigh levels. Predators(both foxes and birds) Snowmelted rapidly and ice broke-upon smallrivers on reproducedsuccessfully. Snowy Owls spread to southern 22 June. Mild weatherin first half of Julywas favourable tundrasto breed and they had big clutchesthere. The for birds. However,a cyclonewith snow stormsbetween proportionof densoccupied by ArcticFoxes in the 19 and 23 July resultedin deep snow-coverthat caused westernTaymyr was 38%-40% in arctictundras, and up the death of manywader broodsand some late clutches. to 90% in typicaltundras (Ust'-Tareya). In eastern The abundanceof the Siberianand CollaredLemmings Taymyrthese proportionswere respectively64% (Bikada was moderateand their summerreproduction was good. river)and 81% (KhatangaBay coast). In mid-July,in the ArcticFoxes and SnowyOwls did not reproduceand they basin of the Pura river, the abundance of waders almostdid not occur. The numberof breedingskuas attendingchicks was low; in the Piasinadelta, at the end increaseda littlein the season, but only a few Pomarine of July it was also lowerthan in 1990. Skua bred. Egg-hatchingsuccess in waderswas highfor Ya. I. Kokorev Grey Plover(94ø/o), Knot Calidriscanutus (84%), and Turnstone;it was moderatefor SanderlingCalidris alba (61%), LittleStint (47%) and CurlewSandpiper (40%). 15. WESTERN TAYMYR-THE PYASINADELTA Taking intoconsideration the influenceof weather on wader broods, it was estimated that the success of their Springseemed to be very late and about50% of the area breedingwas moderate or a little lowerthan average. was still snow-covered on 25 June. Later on, however the M. Yu. Solov'iev, P.S. Tomkovich, 0. Hilden & V. 0. Yakovlev weatherwas generallymild with air temperatureoften exceeded20øC (up to 30øC). Letomingswere extremely numerousin mid-June when snow melted, but the populationcrashed afterwards and not manyanimals 18. SEVERNAYAZEMLYAARCHIPELAGO-BOL'SHEVIK survivedto mid-July. PomarineSkua bred densely(c. 2 ISLAND nests/km2).Snowy Owl and Rough-leggedBuzzard bred also. Waderdensities appeared to be ratherlow, The tundrahabitat of this site is calleda polardesert. probablyas a resultof the late spring. LittleStint Calidris Weather conditions were not favourable for birds. minutawas the mostnumerous breeding wader (up to 60 Summerwas extremelyshort and cool. Air temperature nests/km2 on a 0.25 km2 plot),followed by the muchless from mid-Julyto mid-Augustwas about 0ø C, and only on numerousCurlew Sandpiper Calidris ferruginea and 27 July did it reach +6øC. Heavy cycloneswith snow PacificGolden Plover. DunlinC. alpina,Grey Plover, occurredtwice during summer. The populationof the TurnstoneArenaria interpres, Red-necked Phalarope and Collared Lemmingwas at a minimalstage of abundance. Grey PhalaropePhalaropus fulicarius were all scarce. Breedingsuccess of the onlywader, Purple Sandpiper RingedPlover bred alongthe sea shore(0.6 pairs/km). Calidrismaritima, was moderate.The breedingperiod Clutchpredation by ArcticFoxes was very heavy, and c. was relativelyprolonged. 80% of nestswere eventuallypredated. Such heavyfox A. E. Volkov, V. I. Pridatko & V. I. Bulavintsev predationin a lemmingpeak-year was surprisingand mightbe the resultof rapiddeclines in lemmingnumbers in late Juneand/or the presenceof a specialisedfox 19. NORTH-EASTERN TAYMYR-ARCTICTUNDRAS IN individualin the studyarea. THE VICINITY OF THE PRONCHISHCHEV LAKE P. Chylarecki& W. Kania Snow melted late, at the beginningof July. Weather in the firsttwenty days of Julywas mildand relativelywarm, 16. CENTRALTAYMYR- MIDDLEVERKHNAYATAYMYRA whilstfrom 21 Julyto mid-Augustit was rainy,misty and cold. On 22-23 Julythe tundrawas coveredwith snow. In the area of typicaltundra there was a normalspring. The densityof lemmingswas high,and of ArcticFoxes, Snow-coverwas notvery thick and it meltedquickly. The moderate. The influence of foxes on clutches was not first half of summerwas warm, and Augustwas rainy. It noted. SnowyOwl, PomarineSkua, Long-tailedSkua, snowedon 24 July. The abundanceof lemmingsand HerringGull argentatusand GlaucousGull L. ArcticFoxes was the highestof the last nine years. All hyperboreusall bred successfully.Owls occurred densely densfound in a plotof 110 km2 were occupiedby Arctic and had largeclutches (8.5 eggs/pair).Breeding was Foxes(12 pairs). In the same area, 11 SnowyOwl nests successfulfor the CurlewSandpiper, Turnstone, Little were foundwith 8-11 nestlings/nest.Pomarine Skuas Stint,Grey Plover,Pacific Golden Plover, Sanderling and were also numerous. Ducks,geese and Rough-legged RingedPlover. Single nestsof Knotand Dunlinwere Buzzards bred successfully. The season was favourable found. Totaldensity of breedingwaders on a 12 km2 plot for waders. was 67 nests and families. A. A. Gavrilov E. E. Syroechkovskyjr., E. Lappo,V. Karpov,L. Underhill, R. Prys-Jones,R. Summers,H. Schekkerman& M. van Roomen 17. CENTRALTAYMYR-NORTHERNPART, KNIPOVICH BAY REGION

In thisarea of arctictundra the springstarted one week

23 20. EASTERNTAYMYR-LOWER BOL'SHAYA was very successfulfor all waders. BALAKHNYARIVER E. R. Potapov& V. V. Gavrilov

In this area of typicaltundra the springcame 7-10 days laterthan usually. It delayedthe breedingof waders a 24. ANADYR PLATEAU- THE EL'GYGYTGYN LAKE little. Summer weather was favourable for birds. On 21- 22 Julysnow occurred, but it disappearedquickly• At the Summerwas exceptionallyhot and dry:daily air end of June/beginningof July nestsof somewaders temperaturesexceeded 20 ø Co The abundanceof situatedclose to the river(especially of TemminckgsStint) CollaredLemming was at a peak stage and of Siberian becameflooded because of highwater. ArcticFox was Lemmingwas minimal. Numbers of Tundra Vole Microtus not abundant.The numberof lemmings(particularly of oeconornuswere low. Predators(both mammalsand SiberianLemming)was high and their predators, mainly birds)did not influencemarkedly the breedingsuccess of SnowyOwl and PomarineSkua, were breeding. Total waders. predatorpressure on wader clutcheswas not /. V. Dorogoi considerable. P. Yesou 25. ANADYRLIMAN (VICINITYOF ANADYR AND ZEMLYA GEKA) COASTAL PART OF THE REGION BETWEEN ANABAR AND OLENEK RIVERS- BASIN OF THE OYULAKH- The abundance of lemmingsand other rodentswas low or YURYAKH RIVER very low. /. V. Dorogoi The weatherin first half of Augustwas hot,though showersoccurred occasionally. The abundanceof lemmingswas lowerthan moderate, of ArcticFoxes - 26. ANADYR LIMAN-SOUTH-EASTERN COAST moderate. The density of breedingwaders was low, but relativelyhigh for ducks. LittleStint, PacificGolden Beforethe break-upof river-ice(10 June) the weather Plover,Pectoral Sandpiper Ca/idris me/anotos, Grey was windy and misty, it was very hot and dry afterwards. Plover, and Dunlinwere alarmingwith The numberof lemmingsafter winter was moderate. broods. HerringGull, GlaucousGull, Long-tailedSkua Summerweather was abnormallyhot and dry:to the end and PomarineSkua all bred at low or moderatedensity. of Augustshod-term rains occurred only 4-5 times. Arctic E. E. Syroechkovkyjr., E. Lappo,A. Fi/chagov& P. Yesou Foxes in Avtatkuurriver valley seemed to feed mainlyon ptarmigans.Live lemmings were not met. RuddyVole occurredquite numerously in the riverflood plain. 22. BETWEEN RIVERS YANA & INDIGIRKA- A. V. Kondrat•Fev SHIROKOSTAN PENINSULA IN THE VICINITY OF BUSTAKH LAKE AND SW COAST OF BOL'SHOY LYAKHOVSKIYAND KOTEL'NY ISLANDS CONCLUSIONS (NOVOSIBIRSKIYEISLANDS) In the coastalterritory of the Murmanskregion the The abundanceof bothletoming was highor very abundanceof lemmingshas been low for four years. On highin Julyto September. Weatherwas mildeverywhere, the Kanin Peninsulaletomings were also not numerous. locallythe temperaturewas higherthan manyyears In the easternpad of Europeantundras average(in Tiski up to 32 øC). Coolingdown and the (Bol'shezemerskayaTundra, Yugorskiy Peninsula, onset of snow started one to two weeks later than usual. Vaygach Island)lemmings were numerous,though not at Manyowls with young and ArcticFoxes appeared at the the peripheryof this region. The maximaldensity was coast of the Bol'shoyLyakhovskiy Island. observedin northernpad of the Yamal Peninsula.In the N. Kutuzov centraland southernpad of the Peninsulathe abundance of lemmingswas estimated as moderate or even low. Bothlemming species were highlynumerous on the 23. LOWER KOLYMA Gydan Peninsulaand in great pad of the Taymyr. Their numbers,however were not steadywithin the whole In the regionof the confluenceof the Bol'shaya Taymyr. Lemmingswere mostabundant in centralpad of Kongkovayaand MalayaKon'kovaya (158 ø 30' N, 69ø 30'E) the Taymyr,and their abundancewas lowestin northern breedingof wadersoccurred at the usualtime. Spring pad of the CentralTaymyr (to the northof the Byrranga floods occurred because of thick snow cover. Therefore mountains). Lemmingsdid not occurto the northof the wadersbred patchilybut at highdensity. Junewas cool Taymyron the Bol'shevikIsland. Strongdecreases in and Julyhot. The abundanceof SiberianLemming lemmingnumbers were notedby mid-summerin the increased twice but did not reach the maximal levels. WesternTaymyr. In the great territoryof Yakutia ArcticFoxes were not numerous.Snowy Owl did not (unfortunatelythe informationis ratherscarce from there) breed. Long-tailedSkua, ArcticSkua and Shod-eared it seemedthat lemmingsreproduced numerously Owl Asio f/ammeusbred. Generallythe breedingseason everywhere,reaching the peak level of their abundancein

24 the northernpart of this region(Yana-lndigirka tundra). Most observersworking in tundra habitatsin 1991 had the impressionthat in differentregions between the White It seemed that the distributionof lemmingson the Sea and the AnadyrPlateau the breedingsuccess of Chukotkawas patchyas in previousyears. wadersin 1991 was moderateor high. Only in the WesternTaymyr, where the numberof lemmingshad in a situationof increasingnumbers of lemmingswithin startedto decrease,and in southernYamal, in placeswith great territoryfrom the Bol'shezemerskayaTundra in the low lemmingabundance, where the bird breedingsuccess west to the Kolymain the east, ArcticFoxes and avian- was unexpectedlylow. More detailedstudies carried out predatorshad abundantfood and highlyfavourable in northernand centralYamal and in northernTaymyr conditionsfor reproduction:a highproportion of occupied confirmedthese impressions. fox dens, large SnowyOwl clutchesand highdensities of breedingskuas in someplaces testified to this. Breeding The prognosismade in 1990 that the 1991 breeding of Short-earedOwl was notedby some observersin seasonwould be successfulfor waders,appeared to be southerntundras. Unexpectedly,the low abundanceor correctfor the greaterpart of Eurasiatictundra. Though absenceof Pomarine$kua, SnowyOwl and ArcticFox the densityof lemmingswas not maximalin all places, were notedthere when lemmingnumbers were moderate their numberswere great enoughto attract and in the northof the CentralTaymyr; it is very likelythat avianpredators. This gave the possibilityof better thesepredators settled in moresouthern territories. breedingsuccess for waders and other small birds. Low breedingsuccess of waders, besidesthe Western Springwas earlyin Europeto the eastof the WhiteSea Taymyr,was notedonly in coastalhabitats of the (besidesVaygach Island)and on the Yamal. Summer Murmanskregion, and locallyin Yakutia and Chukotka. was cool withoutextreme changes of weather in the whole of the Europeantundras and on the Yamal (the drought Undoubtedly,as a resultof successfulreproduction of was noticedon the Kola Peninsula).Spring started as predators,their autumnabundance allows to foreseethat usual on the Taymyr (a littlelater in easternTaymyr): mild it will be high in summer1992. Letomingnumber will summerweather was brokenby cyclonesand snow decreasein someplaces or will remainat a high levelin afterwardsat the end of July and in August. This others. However,it may be expectedthat predatorswill adverselyaffected wader chicksin the northof Central reducelemming number soon and then they may reduce Taymyrand on the $evernayaZemlya archipelago. In markedlythe numberof wader clutches. Thus breeding Yakutia,Tazovskiy Peninsula and Chukotkathe middle successof waders in 1992 is predictedto be low or and end of summerwas hot and dry. This situationcould moderate. have limitedfood resources for waderswhich prefer P.S. Tomkovich wetter habitats.

A case of three clutches in the same nest by the same pair of Kentish Plover Charadrius alexandrinus

Juan Antonio Lorenzo

Lorenzo,J.A. 1993. A case of three clutchesin the same nestby the same pair of Kentish PloverCharadrius alexandrinus. Wader Study Group Bull. 71: 25-26. JuanAntonio Lorenzo, Departamento de BiologfaAnimal (Zoologfa), Facultad de Biologfa, Universidadde La Laguna,La Laguna,Tenerife, Islas Canarias,Spain.

INTRODUCTION AND STUDY AREA MOdano,a coastallocality situated in the southof Tenerife Island. This area is characterizedby an interestingsand The KentishPlover Charadrius alexandrinus is a widely derivedenvironment (Wildpret 1970; Lorenzoet al. 1988), distributedwader, with 6 subspecies.The nominaterace, and by an importantornithological community (Lorenzo in C. a. alexandrinus,is presentin Europeand NorthAfrica press). It is a populartourist resort. (Cramp & Simmons1983). In recentyears, this populationhas decreaseddrastically, resulting in increasedpriority being given to the studyof the species RESULTS (J•nsson et al. 1990)o Duringthe courseof thisstudy a singlepair of Kentish Hence an extensivestudy on the breedingbiology of this Ploverwas observedto lay three clutchesin the same specieshas beencarried out in the CanaryIslands, at El nest.

25