|
|
RESPONDENT
|
|
Ivan Taldenkov
|
|
|
SITE NAME
|
|
Belyaka Spit, Chukotka, Russia
|
|
| Contact details
(phone/fax//e-mail//address): |
| 8-499-792-7707 // italdenkov@mail.ru; italdenkov@yandex.ru // Molodogvardeiskaya 36-1-71, Moscow, Russia
|
|
PROJECT DETAILS |
|
Project name:
|
|
Joint expedition of the Dept. of Vertebrate Zoology (Moscow Univ.) and Wrangel Island Reserve
|
|
|
Start of survey:
|
End
of survey: |
Team
size: |
|
20.05
|
22.08
|
3
|
|
WEATHER
CONDITIONS
|
| Season phenology: |
average
|
|
|
Weather conditions: |
Spring was relatively late, and a few highest ridges cleared at arrival on 19 May, while the whole flat surface was covered by a layer of snow at least 15-20 cm thick. Air temperatures did not exceed +5øC in late May, while mean daily temperatures were negative. However, inveratabrates were active at the well-warmed patches and greening of willows and sedges was recorded on 27 May.
Snow cover dropped to 50% on 27 May in the coastal tundra, on 5 June in the inland areas of the spit and on 12 June on Yuzhni Island. Snow completely melted on flat surfaces by 15 June in the coastal area. Snow melt occurred 7-10 days earlier at the northen part of the Belyaka Spit than on Yuzhni Island, but was delayed at 4-6 days compared with the southern part of the spit.
Summer was cold and dry. Air temperatures dropped regularly below freezing at night until 20 June, and decreased to -8.5øC on 11 June. The cold weather was associated with small snowfalls and hoarfrost formation. The first notable warming occurred after 10 June when when air temperatures reached +18øC and mean daily temperature raised above freezing. Lakes became completely ice-free by 18-20 June and craneflies, chironomid midges and mosquitoes emerged at the same time. Ice-break on the channel between Belyaka Spit and Yuzhni Island occured at night on 27 June which was 12 days later than in 2002 but earlier than in 1986-88 (1-9 July). July was cool, but temperatures did not drop below +5øC in August. The weather was considerably affected by cold northerly or warm southerly winds. Rains were rare and had no apparent impact on birds.
|
|
|
|
|
|
| Date of 50%
snow-cover: |
27.05-5.06
|
|
| Date of ice-break on
rivers: |
|
|
| Date of final loss of
snow: |
15.06
|
|
BIOTIC
CONDITIONS
|
| Rodents abundance evaluation: |
average
|
|
|
Breeding conditions:
|
Territorial pairs of Sandhill Cranes, singing Snow Buntings, Lapland Buntings and Wheatears were observed from the start of studies on 20 May. Most species of local waders arrived from 23-31 May, while waterfowl and phalaropes became common after 25 May when open water appeared on coastal lakes and pools in depressions. Copulation of phalaropes was observed on 30 May, while complete clutch of Sandhill Cranes was found on 31 May. The first nest of Dunlin with a clutch of 1 egg was found on 4 June, and a clutch of Emperor Goose with 7 eggs was found on 15 June. Hatching was recorded on 14 June in Lapland Buntings.
Arctic Foxes were abundant and we recorded 1-3 animals daily in the coastal tundra. They actively hunted Tundra Voles in spring and early summer, and 5 voles bodies were found in a stomach of an Arctic Fox female on 29 May. Although 2 Arctic Fox females were eliminated from the camp vicinity on 29 May and 2 July, we discovered in mid July 2 dens with broods, one of which contained 5-6 approximately one month old cubs. Two more dens inhabited in 2005 were found at a patch of coastal tundra 8-10 km long in the south-western part of the spit. Two adult Arctic Foxes were observed on Yuzhni Island on 19 May and 13 June, while a juvenile animal was recorded there on 28 July. Arctic Foxes destroyed clutches of Emperor Goose, Temminck's Stint and Grey Phalarope; they also took chicks of Spoon-billed Sandpiper, killed Temminck's Stint female at the nest, but failed to destroy a clutch of White-billed Diver. A considerable increase of clutch and chick loss in waders in the study area in the first half of July was probably due to increase of food demand by growing cubs of Arctic Foxes.
Brown Bears were recorded on sevaral occasions on the spit, and one clutch of Sandhill Cranes was destroyed by dogs following tractor of reindeer herders.
We recorded Peregrine Falcon, White-tailed Sea Eagle, solitary birds and pairs of Rough-legged Buzzards, but none of these species bred. A hunting Snowy Owl female was observd in late May, while Short-earted Owls were recorded on several occasions. Skuas did not breed, among them Long-tailed and Arctic were common and Pomarine rare. A single clutch of Grey Phalropes was presumably destroyed by an avian predator.
Herring Gulls and Glaucous Gulls were numerous in the area and raised chicks successfully, primarily in small colonies along shoreline and on islands of the spit lakes. Kittiwakes occurres in 100s on the sea and occasionally visited coastal lakes. Ravens were seen daily but their breeding status was not determined. Sandhill Cranes were common, and one nest survived to hatching in this species.
Breeding success of waterfowl was not high. We found nests of Red-throated, Pacific and White-billed divers, Emperor Goos, Common Eider and Long-tailed Duck, but only clutches of Pacific and White-billed divers and Common Eider survived to hatching. Nests of Common Eiders were particularly successfull in the camp vicinity. Waterfowl nest success was probably higher on Yuzhni Island, as broods of Common Eiders were common there, and we also recorded a brood of Pintail. on the island.
Nest success of waders was high compared with the previous years, as approximately one third of clutches found in June were destroyed. Hatching was recorded in Dunlins, Spoon-billed Sandpipers, Temminck's Stints, Rock, Western, Red-necked and Pectoral sandpipers, Red-necked and Grey phalaropes, Ringed Plovers and Turnstones. However, predation pressure increased considerably in early and mid July in the study area which led to low survival of late clutches and increased mortality of chicks in waders. While the latter could not be precisely evaluated, we estimated that less than half of hatching chicks survived to fledging. Overall reproductive success of most wader species can be evaluated as average, also based on observations on Yuzhni Island in late July. Passerines bred successfully, due to early fledging, and juvenile Snow Buntings and Lapland Buntings were numerous in the secons half of summer.
|
|
|
Rodent dynamics:
|
| Tundra Voles were common in the coastal dry tundra on sandy banks with grasses and driftwood, and particularly in the camp vicinity. Lemmings were not recorded, but their undersnow nests and pathways were found in moss tussocks, usually along shoreline of tundra lakes. Numerous burrows and undersnow nests, as well as bodies of Collared Lemmings were found in a hilly tundra at the western coast of the Kolyuchiskaya Bay. These observations along with high numbers of Arctic Foxes in 2005 indicated high lemming abundance in 2004. Unlike 2002 Arctic Ground Squirrels were common and bred successfully in 2005 in the coastal tundra, particularly in the camp vicinity. Their numbers increased in the second half of July when juveniles were leaving burrows.
|
|
Rodent species recorded:
|
| Latin | Abundance |
|---|
| Microtus oeconomus | common |
| Citellus parryi | common |
|
|
|
Summary
of fauna studies: |
| Population studies of Spoon-billed Sandpipers and other waders were conducted.
|
|