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RESPONDENT
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Pavel Tomkovich
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SITE NAME
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Belyaka Spit, Chukotka, Russia
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| Contact details
(phone/fax//e-mail//address): |
| (495)6294474/(495)629-48-25(fax, for P. Tomkovich) // pst@zmmu.msu.ru // Zoological Museum, Bolshaya Nikitskaya St., 6, Moscow, 125009, Russia
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PROJECT DETAILS |
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Project name:
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International Arctic Expedition of the Inst. of Ecology and Evolution
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Start of survey:
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End
of survey: |
Team
size: |
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28.05
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31.07
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6
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WEATHER
CONDITIONS
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Weather conditions: |
| Spring and summer were very early, warm and dry which is unusual for the north of the Chukotsky Peninsula, and affected plant, invertebrate and bird breeding phenology. Snow cover was reduced to 50% before the end of May, and had gone completely from level areas by 7 June. Waterfowl were able to utilize clear water on lakes already in late May. Mean day air temperature raised above freezing point on 1 June, and did not drop below it during period of surveys. Maximum air temperatures generally were above +10øC, while minimum dropped below freezing only twice after 3 June. Most lakes completely cleared from ice by mid June, except for the largest where ice retained until late June. Ice broke on 15 June in the mouth of the Kolyuchinskaya Gulf channel which is considerably earlier than in 1986-1988 (1-9 July). First flowering willows Salix chamissonis were found on the southern slope of coastal dune already in the first day of studies on 28 May, while mass flowering occurred from 3 June. Greening of willow buds and leaves of sedges started from 7 June, caddis flies appeared in mass on 3 June, Chironomidae and craneflies (Tipulidae) on 14 June. First mosquitoes and and moths were seen on 14 June, while from 16 June first butterflies were recorded. These events indicate development of phenological events approximately 2 weeks earlier compared with previous observations. Snowfalls occurred only twice during summer (23-24 June and 2/3 July), but snow cover exsited for less than half an day on both occasions and did not affect considerably bird reproduction.
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| Date of ice-break on
rivers: |
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| Date of final loss of
snow: |
6.06
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BIOTIC
CONDITIONS
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| Rodents abundance evaluation: |
low
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Breeding conditions:
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Arctic Foxes were numerous, and were seen almost daily up to 3 times a day in June. Difference in coloration after start of moult allowed to individually distinguish at least 5 animals at the northern part of the spit. Interestingly, fox abundance decrease in July to 11 visual records from 47 records in June. Despite low abundance of lemmings one pair of foxes bred and had 2 cubs in a den on Southern Island in July. None of the avian predators bred. Observations of Snowy and Short-eared owls were solitary.
Early spring development led to early arrival and start of reproduction by birds. Shift of timing of breeding was more pronounced in waterfowl than in waders. First White-billed Divers arrived already in late May, Red-throated Divers on 1 June. Divers had complete clutches before 20 June, while first incubating Emperor Goose was found on 10 June. Among waders Turnstones were the earliest breeders with the first complete clutch on 6 June. Spoon-billed Sandpipers arrived on 2 June, which is only 1 day earlier than previously recorded dates, and started egg-laying on 8 June. Average clutch and brood size after hatching were higher in this species compared with previously collected data.
Predation pressure on bird clutches was high. In many species clutches of many species were destroyed completely: divers (except White-billed Diver), Emperor Geese, Pintail, gulls, Grey Plover. Solitary broods of Common Eider and Long-tailed Duck were seen in July. Large birds (White-billed Diver, Whistling Swan and Sandhill Crane), probably, suffered less from predation, because broods of these species were observed. Ducks and waders were able to gain some reproductive success on behalf of replacement clutches given decrease of Arctic Fox abundance in July. Hatching probabilities (using the Mayfield method) were: Spoon-billed Sandpiper 40.2ñ3.3% (n=16); Temminck's Stint 25.4ñ4.1% (n=11); Turnstone 19.9ñ6.3% (n=7), and for 11 wader species combined 31,4ñ2.1% (n=42). Chick survival was, probably, high.
Numbers of Red-throated Diver, Long-tailed Duck, Grey Plover, Spoon-billed Sandpiper, Dunlin, Arctic Tern, and, probably, of Grey Phalarope and Herring Gull decreased compared with their numbers in 1970s and 1980s. In contrast, numbers of Red-throated and White-billed divers, Emperor Goose, Whistling Swan, Ringed Plover, Temminck's Stint, Rock Sandpiper and Glaucous Gull increased.
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Rodent dynamics:
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| Lemming number was low: a Single Brown Lemming was seen in spring. Presumably, numbers decreased during winter, as under-snow nests, tracks in snow and other signs of activity were found. Peak numbers likely occurred in 2001, as last year nests of Rough-legged Buzzards were found on onshore navigation beacons both on the Belyaka Spit and Yuzhny Island. Number of American Ground Squirrels was also very lwo, and only 4 animals were seen during the whole summer. Root Voles were locally abundant near hut.
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Rodent species recorded:
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| Latin | Abundance |
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| Lemmus trimucronatus | rare |
| Microtus oeconomus | common |
| Citellus parryi | rare |
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Summary
of fauna studies: |
| Numbers of several bird species were assessed by territory mapping of and nest searches on the northen part of the Belyaka Spit, and fate of found nests was monitored. Numbers and productivity of Spoon-billed Sandpiper were in the focus of the research.
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