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RESPONDENT
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Vasily Sokolov
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SITE NAME
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Erkatayakha and Payutayakha rivers, Yamal, Russia
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| Contact details
(phone/fax//e-mail//address): |
| (343) 210-3858, add. 104/89028432787 // vsokolov@inbox.ru // Lab. of biocenological processes, Inst. of plant and animal ecology, 8 Marta Str, 202, Ekaterinburg, 620144 Russia
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PROJECT DETAILS |
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Project name:
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Long-term monitoring of bird and rodent populations on the south-western Yamal
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Start of survey:
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End
of survey: |
Team
size: |
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1.06
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21.06
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5
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WEATHER
CONDITIONS
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Weather conditions: |
| Spring was the latest on record for the last 7 years, and it was still possible to cross the Erkatayakha River on snowmobiles in late May. Ice broke on 5-7 June. Snow cover reduced to 80% at our arrival on 2 June, to 50% on 3-5 June and completely melted on 8-10 June. However, all breeding species of birds of the area were recorded in early June. Large flocks of geese of up to 300 birds were regularly observed from 1-10 June. Weakened Barn Swallow was found by local people on the roof of their house in late May. A Brown Bear was shot by local people 30 km to the south of the study area near railway bridge on 25 May. Relatively warm rainy weather in early June resulted in intensive snowmelt which combined with heavy ice in the Baidaratskaya Bay at this time caused unusually high and torrential flood. The highest water level was reached on 8 June when almost entire vicinity went under water. Riverbed was only marked by few bluffy banks. Early June was relatively warm, with moderate winds and air temperature reaching +5-7øC at day-time. Driblle occurred often and lasted for up to 24 hours. The first mosquitoes appeared on 10 June. In spite of late snowmelt and ice-break two southern species, Terek Sandpiper and Brambling, were recorded in the area, several times each. North-western and western winds prevailed from 10-20 June, and rains were common. Extreme weather events were not recorded in the study period from 1-21 June.
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| Date of 50%
snow-cover: |
3-5.06
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| Date of ice-break on
rivers: |
5-7.06
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| Date of final loss of
snow: |
8-10.06
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BIOTIC
CONDITIONS
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| Rodents abundance evaluation: |
average
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Breeding conditions:
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Arctic Foxes were relatively common in the first half of June. Snowy and Short-eared owls were rare and did not breed. Migration of Pomarine Skuas was notable on 3-4 June, when 6-8 flocks of up to 15 birds each were recorded flying to the east. Common Arctic Skuas were regularly recorded in flocks of 4-5 birds in the study area and bred, while breeding status of rare Long-tailed Skuas was not confirmed.
White-fronted Geese were relatively abundant in the area in early June, and we discovered signs of intensive spring hunting on waterfowl, geese wings and skin of Bewick's Swan, in the river vicinity. The river floodplain remained under water until the second half of June due to high flood, which probably resulted in more prolonged breeding of several species, as their nests were were found both in uplands and in the floodplain after the retreat of water. A nest of Lesser White-fronted Geese with a clutch of 4 eggs was found on a bluff, while previously the breeding status of this species was evidenced only by records of broods. The earliest records of nests included a nest of Wood Sandpiper with a clutch of 4 eggs found on 12 June, a nest of Red-throated Pipit with a clutch of 5 eggs found on 16 June and a nest of Pintail with a clutch of 6 eggs found on 10 June (was destroyed by Arctic Fox on 18 June).
Considering realtively late spring, high flood, low lemming abundance and frequent observations of Arctic Foxes reproductive success of birds was probably low in the area.
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Rodent dynamics:
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| Lemming numbers were not high, however, Siberian Lemming was captured for the first time for the last 5 years. Middendorff's and Narrow-skulled voles were common.
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Rodent species recorded:
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| Latin | Abundance |
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| Lemmus sibiricus | rare |
| Dicrostonyx torquatus | rare |
| Microtus middendorffi | common |
| Microtus gregalis | common |
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Summary
of fauna studies: |
| Absolute bird counts were conducted on plots using mapping. Plot sizes were 10 sq.km for ducks and large waders and 4 sq.km for passerines and samll waders.
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