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Weather conditions: |
| Spring was late, and less than 10% of tundra was snow free at arrival on 11.06. Mean daily temperatures went above freezing point 17.06, but freezing air temperatures were recorded until 22.06. Snowfalls were not recorded in spring and summer, but from 11-20.06 snow squalls were registered several times. Flood occurred on 22-24.06 on mountain rivres, and shallow Ledyanaya Bay was filled with water by 26.06. Ice break was recorded on the Verkhnyaya Taimyra River in the vicinity of Rysyukova cape on 2.07, which was considerably later than average (25-28.06). Mean daily air temperatures rose above +5øC on 4.07, but failed to rise above +10øC during summer. Mean air temperatures were +3.5øC, +9.6øC and 6.3øC in the periods 11-30.06, 1-31.07 and 1-15.08, respectively. Precipitation occurred on 60% of days in July and the first half of August, but pelting rains were not recorded. Wind speed reached 18 m/s on several days in July. Water table in the bay started to drop rapidly in late July, and at least 40% of the bay surface turned into mud and stony flats by 15.08. These flats attracted migrating waders in high numbers: we counted at least 1000 Dunlins, Curlew Sandpipers and Little Stints at an area of approximately 5 sq.km on 13-15.08. Autumn was, probably, early in the area, as snow cover established in the mountains at altitude above 300 m on 12.08.
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| Rodents abundance evaluation: |
average
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Breeding conditions:
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Arctic Foxes were seen regularly. Among 24 dens of Arctic Foxes 5 contained broods, ranging from 2-4 cubs, while another 8 dens were inhabited, but not by breeding animals. An Arctic Fox brood of 5 cubs was found in spring in a shallow pit in tundra, outside of den. Although lemming numbers were not low Arctic Foxes destroyed considerable number of bird clutches, including 3 nests of Little Stints, 2 of Ringed Plovers 2 of Lapland Buntings, 1 of White-fronted Goose, all not farther than 3 km from the field camp. Wolverine was seen on 3 occasions, which is a high rate, considering 2 encounters by the author during 10 previous years. Tracks of wolves were common.
Mass migration of reindeers to the north occurred from 23.07-5.08 along northern coast of the bay to the valleys of rivers Uglenosnaya and Karovaya. Five to seven thousand of animals passed by during this period, and based on the condition of habitats they probably migrate in similar numbers every year. Two nests of Red-throated Divers were trampled by reindeers.
Herring Gull, Lapland Bunting, Snow Bunting, Ringed Plover, Rock Ptarmigan, White-fronted Goose and Bean Goose were already present in the area at arrival on 11.06. Mass arrival of birds occurred from 12-20.06, including Grey Plover, Turnstone and Little Stint on 13.06, Dotterel and Pacific Golden Plover on 14.06, Temminck's Stint and Long-tailed Duck on 17.06, Shorelark, Wheatear, Brent Goose and Grey Phalarope on 18.06. Red-throated Diver and Steller's Eider arrived on 25.06, and Bluethroat arrived on 26.06. These dates were considerably later than average for the area, and were close to arrival dates in the vicinity of Lake Levinson-Lessing, 30 km to the northeast, in extremaly late spring 1996.
Prolonged snow melt resulted in aggregated nesting of several species of birds, e.g., Ringed Plovers nested in groups of 3-4 pairs on the first snow-free patches of gravel flats, while available patches of tundra were inhabited at higher density by Little Stints, Pacific Golden Plover, Lapland Bunting. Nesting started from 18-26.06 in waders, with Ringed Plovers and Little Stints being the earliest breeders. Hatching was recorded on 9.07 in Lapland Bunting, on 13.07 in Little Stint, on 15.07 in Grey Plover, Curlew Sandpiper and Rock Ptarmigan, on 20.07 in King Eider, on 22.07 in Temminck's Stint, on 25.07 in Steller's Eider and Rough-legged Buzzard and on 1.08 in Red-throated Diver. Fledgelings were observd on 22.07 in Snow Bunting, on 26.07 in Wheatear, on 29.07 in Lapland Bunting, on 28.07 in Little Stint, on 4.08 in Rock Ptarmigan, on 5.08 in Curlew Sandpiper, on 9.08 in Pacific Golden Plover and on 16.08 in Bluethroat. Dunlins and Curlew Sandpipers were actively moulting in the second week of August.
Among 44 species of birds recorded in the area 23 species bred and 6 belonged to unconfirmed breeders. Numbers of most species were low. Lapland Bunting, Pacific Golden Plover, Dunlin and Snow Bunting were the only numerous species (Snow Bunting in the mountains). Curlew Sandpiper, Little Stint, Grey Plover, Ringed Plover, King Eider and Rock Ptarmigan were common, while several species occured only in specific habitats: Bluethroat in willow bushes along rivers, Dotterel, White Wagtail and Wheatear in the mountains. Shorelark was very rare and its nesting was not confirmed which is unusual for typical and arctic tundra subzones on Taimyr. Arctic Tern, Pectoral Sandpiper, Ruff and Red-necked Phalarope were also rare. Skuas were rare, and a single breeding pair of Arctic Skuas was recorded. Herring Gulls were rare breeders in contrasting habitats: along lake shores and on limestone rocks 15 km to the north of the bay. Limestone plateau was also used for nesting by Ringed Plover along a typical for this species habitat - gravel flats. Three nesting pairs of Rough-legged Buzzards were found in an area of 300 sq.km, and one more nest was deserted in the very beginning of the season.
Snowy Owls were recorded as wandering birds. Three flocks of moulting geese 70-100 birds each were seen in Ledyanaya Bay, but numbers could be higher in other years as indicated by old feathers found on beaches.
Hatching success of birds was 53.3% (n=30), including 53.8% in waders (n=13).
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