Breeding conditions for waders in the tundras of Russia in 1991 Vadim K. Ryabitsev (ed.) (translatedby JadwigaGromadzka) Ryabitsev,V.Ko 1993. Breedingconditions for waders in the tundrasof Russiain 1991. Wader 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 birds. 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 tundra 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 lemmings 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. Voles were very numerous are comparedagainst the real situationbelow. in willowthickets. Rough-legged Buzzard Buteo lagopus and Snowy Owl 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,Ruff 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 Vole Clethrionomys Amongstbirds of prey only Rough-leggedBuzzards were rut#us and maximal for Narrow-sculled Vole Microtus 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 Lemming 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 mammals rodents. Foxes bred successfully,but they were not (Short-tailedVole Microtusagrestis, Ground Vole Arvicola 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 Kara Sea), 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