|
|
|
Weather conditions: |
| Observations were carried out from 29 May to 12 August. In all upland habitats snow was present only in deep ravines by the end of May. Coastal marshes were still approximately 50% snow-covered. Mean daily air temperatures were above freezing point, and only on 5-7 June temperatures were freezing at night. Maximum daily temperatures exceeded +16øC only on 4, 20-26 June, 9-14 and 18-19 July. The majority of days were cloudy, precipitation occurred regularly, and wind speed exceeded 6-8 m/s on most of the days.
|
|
| Rodents abundance evaluation: |
|
|
|
Breeding conditions:
|
The first Barnacle and White-fronted geese arrived on 17-18 May, according to reports of locals from Bugrino village. Their mass arrival occurred after 27 May, and the number of White-fronted Geese continued to increase until 6 June.
First nests of Bean Geese were found on 29 May, of Barnacle Geese on 2 June in the main colony at lower Peschanka River, of White-fronted Geese on 3 June.
Arctic Foxes were common and bred successfully; 5 their inhabited dens were found within 5 km from the camp, with up to 7-9 pups. All food remains near dens belonged to geese (mostly Barnacle Geese). Red Foxes were seen several times on banks of the Peschanka River, mostly on the northern bank, but inhabited dens of Red Fox were not found.
Arctic Skuas were common and bred successfully. Breeding of the Great Skua was recorded. Glaucous and Herring Gulls were rather abundant (over 250 pairs bred solitarily and in colonies in the Peschanka River valley including its delta). Glaucous Gulls and Arctic Skuas predated clutches and especially chicks of all geese species.
Peregrine Falcons bred successfully, with 4 nests containing 4 chicks each, and only one nest contained 3 chicks due to perishing of one chick soon after hatching. Remains of Ruffs prevailed near falcon nests during incubation while chick diet included Dunlins, Grey and Golden plovers and Turnstones. Hatching occurred on 1-12 July in different nests. Dense goose colonies were found within 150 m of nests of Peregrine Falcons, one of which consisted of more than 40 nests of 3 species.
Three nests of Rough-legged Buzzards with 2, 2 and 4 eggs were found at lower Peschanka area at an average distance of 2 km from each other. Adult birds were catching Willow Grouse during incubation and fed chicks with goslings and ducklings of various species. Hatching occurred on 30 June in buzzards.
Short-eared Owl was seen only once during spring migration, and one male Snowy Owl stayed in the Peschanka River delta during summer, feeding on geese.
The size of the Barnacle Goose colony at the lower Peschanka River, including the Paarkov River delta, was estimated ca. 47,000 breeding pairs in total.
Nest success of Barnacle Geese was high and reached 95% on the main part of their colony. White-fronted geese bred at a density of 51-59 nests/km2, and nest success 90%. Bean Geese bred at a density of 1-2 pairs/km2 in coastal areas and ca. 30 nests/km2 in central parts of the island, 10 km inland from the coastline. Their nest success was 77%.
Mean clutch size was 3.5, 3.7 and 3.6 eggs and mean brood size at hatching 3.2, 2.7 and 3.2 goslings in White-fronted, Bean and Barnacle geese, respectively. Brood size at fledgling was 2.2 young in Barnacle Geese and 1.8 young in White-fronted Geese.
Bewick's Swans nested successfully in the Peschanka River valley (20 broods in total), with an average clutch size of 4.5 eggs (n=8). King Eiders bred at high density in the area of the Peschanka lagoon. Greater Scaups were common in the Peschanka River valley, with a density over 10 nests/km2. Long-Tailed Ducks were common on inland lakes. Pintails and Teals were recorded breeding in the river valley, and Velvet and Common Scoters on upland and valley lakes.
First flightless moulting non-breeding Barnacle and Bean geese were recorded on 4 July. First adults on wing were seen on 6 August, and first broods of flying young were observed after 10 August.
Among waders the Dunlin, Ringed Plover, and Temmink's Stint were abundant and widespread breeders. Leks of Ruffs were common on the bluffs of the Peschanka River valley; Reeves and juvenile Ruffs were common in August in bogs of the river floodplain. Breeding of the Little Stint and Red-necked Phalarope was recorded at several sites. Grey and Golden plovers were common in the coastal area and inland, respectively. Breeding Turnstones were found at 2 localities only.
Common Snipes were occasionally heard and seen in the Peschanka River valley. Displaying Jack Snipes were heard and seen at many places of the same area. Wood Sandpipers were recorded displaying in shrubs of the Peschanka River. Oystercatchers were found breeding at the eastern and southern sandy spits of the island. Nesting densities of Dunlin and Turnstone decreased considerably in the area compared with 1995.
Large post-breeding aggregations of waders were found on mudflats of the Peschanka Lagoon and on eastern spits from late June till late July. The biggest concentration consisted of ca. 10,000 birds, and others consisted of 2000, 800 and 400 waders. Dunlins formed a majority of these flocks, but Purple Sandpipers and Sanderlings were also recorded.
Generally, breeding success of waders was high, as few records of nest failure were documented and numerous broods were observed. Broods of the Dunlin, Temmink's Stint and Ringed Plover were particularly common, but broods of the Little Stint, Red-necked Phalarope, Grey and Golden plovers and Ruff were also recorded.
|
|