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RESPONDENT
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Alexander Artyukhov
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SITE NAME
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Vaamochka River delta, Koryak highlands, Russia
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| Contact details
(phone/fax//e-mail//address): |
| 8(083)4124632 // // Sovetskaya St., 3-60, Kokino, Bryanskaya oblast, 243365, Russia
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PROJECT DETAILS |
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Start of survey:
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End
of survey: |
Team
size: |
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WEATHER
CONDITIONS
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Weather conditions: |
| Stormy weather in autumn 2003 resulted in blocking of the river mouth with dam from sand and pebble. Ice on waterbodies was unusually thin, ranging from 30-40 cm compared with normal 100-150 cm. Spring was warm and very early, with high flood. Water table in Pykulneiskoe and Vaamochka lakes was very high, only 30 cm below the record highest level observed in 2001. Until 17 June, when the dam was broken, the high water level retained, and vast lowlands around lakes and in river valleys remained flooded and unsuitable for nesting of most species of waterbirds almost until the end of June. Ice melted on large lakes from 7-10 days earlier than in 2003. Many relatively large snowpatches remained in ravines until mid July. Minimal and maximal air temperatures were +1-4øC and +7-16øC from 18-30 June, and +2-9øC and +7-26øC in July, respectively. Summer was generally cool and windy with low clouds, high air humidity, night fogs, drizzle and frequent rains. Heavy rains occurred several times when more than 25 mm precipitated for 24 hours, but this did not result in considerable increase of water table in rivers. Total amount of precipitation was approximately 3 times higher than in 2003. Ripening of berries (crowberries, bog bilberries, clusterberries and cloudberries) was several days later than in 2003, while the crop was close to average. Salmons appeared in good numbers in rivers at spawning time.
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| Date of ice-break on
rivers: |
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| Date of final loss of
snow: |
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BIOTIC
CONDITIONS
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| Rodents abundance evaluation: |
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Breeding conditions:
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Red Foxes were common to numerous, most of them bred and consumed actively eggs of birds until mid July. Brown Bears were numerous, and at least 25 different adult animals were recorded, including 3 females with cubs. Fresh tracks and excrements were seen daily. A majority of bears had no permanent territories outside of the vicinity of spawning rivers. Fresh tracks of wolves and a track of wolverine were seen.
Observations of Gyrfalcon, Peregrine and Merlin were solitary, while records of wandering White-tailed Sea Eagles rare. Two breeding pairs of Rough-legged Buzzard were found. Wandering Herring Gulls were abundant, while numbers of nesting birds were 2-3 times lower than in 2003, and they were often found in tundra up to 400 m away from waterbodies. Common Gulls were also less abundant than in 2003. Mammalian predators destroyed 60-80% of nests outside of islands in these two gull species. Wandering Arctic Skuas were rare, and only two nesting pairs were recorded. Long-tailed Skuas were also very rare and did not bred. Ravens were relatively numerous, and at least 15 pairs nested on rocks along 15 length of the Vaamochka River. Ravens were principal avian predators on bird clutches, in partuclarly affecting geese and ducks flashed from nests by humans.
Breeding dates were close to 2003 in most species of birds, but proportion of non-breeders was very high. Numbers of nesting divers, Red-necked Grebes and most species of ducks was considerably lower than in 2003. Swans did not breed. Numbers of nesting White-fronted Geese were 2-3 times lower than in 2003, and approximately half of clutches were predated. Teal, Harlequin Duck and Red-breasted Merganser were the only species of ducks which numbers increased compared with 2003. Numbers of moulting White-fronted Geese increased 2.5-3 times compared with 2003, and reached 3000-3500 birds. Willow Grouse were rare, and a single juvenile was seen. Sandhill Cranes occurred in similar to 2003 numbers, but only 10-20% of birds nested, and no more than half of nests survived to hatching. Non-breeding cranes wandered in vicinity of breeding sites in flocks up to 11 birds.
Numbers of most species of waders (Temminck' Stint, Curlew Sandpiper, Ruff and Common Snipe) decreased compared with 2003. Density of Lesser Sand Plover was 3-8 times lower than in 2003. Long-toed Stint and Wood Sandpiper nested in numbers close to 2003, while Red-necked Phalaropes became twice more abundant.
Most species of passerines nested at lower density than in 2003. Redpolls were numerous in floodplain willow stands in July, but small proportion of these birds nested, and primarily in alder stands on mountain slopes. Numbers of White Wagtail and Wheatear increased 2-3 and 3-4 times, respectively.
Mass non-breeding of birds in the flooded areas did not lead to increase of breeding bird numbers in surrounding territories.
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Rodent dynamics:
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| Lemmings were not recorded, while numbers of voles were higher than in 2003, in particular, on dry banks of rivers and some lakes. Shrews were rare. Arctic Ground Squirrels were abundant, as in 2003, and successfully bred. Hares were very rare.
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Rodent species recorded:
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Summary
of fauna studies: |
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