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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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Dynamics of bird populations on the south-west Yamal |
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Start of survey:
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End
of survey:
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Team
size:
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1.06 |
29.09 |
4 |
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WEATHER CONDITIONS
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Weather conditions: |
| Ice broke on 26 May on the Erkatayakha River, and on 1 June on the Payutayakha river. Despite relatively early snowmelt and ice-break summer was cold and rainy. During arrival of most birds from 20 May we did not observe extremal weather events, which could have resulted in backward migration. However, steady northern winds, frequently with wet snow and rain, and low temperatures (+1-+3øC) were common in the beginning and middle of June, which contributed to prolonged character of nesting period in many birds, in particular passerines. Absence of strong winds and low amount of precipitation in late June created favourable weather conditions. July and August were rainy and relatively cold, with some rains going for 3 days. Given relatively low abundance of lemmings poor weather negatively affected broods of birds, in particular birds of prey. However, loss of clutches by passerines and ducks, as well as chicks by passerines after continuous dirty weather was not uncommon. September was rainy and cold with frequent snowfalls and strong winds. Geese migrated during a short time interval from 19 to 25 September. |
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| Date of 50%
snow-cover: |
20-25 May |
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| Date of ice-break
on rivers: |
26.05-1.06 |
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| Date of final loss
of snow: |
5-7.06 |
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BIOTIC CONDITIONS
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| Rodents abundance evaluation: |
average |
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Breeding conditions:
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Numbers of Arctic Foxes were relatively high, and pressure of predators on birds was substantial. Observations of skuas, Arctic Foxes and, occasionally, Rough-legged Buzzards destroying nests of passerines and ducks were not uncommon, likewise records of egg-shells on excursions. One nest of White-fronted Geese was destroyed by White-tailed Sea-eagle.
Prolonged flooding of river floodplains hindered nesting of many bird species. We often found nests, presumably replacement, of passerines, ducks and waders in late June, as well as deserted clutches. |
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Rodent dynamics:
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| Under-snow reproduction of lemmings and voles was successful, judging by high numbers of nests, droppings and burrows. However, numerous dead animals, both juvenile and adult, were discovered after snowmelt, and numbers of lemmings in summer were relatively low.
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Rodent species recorded:
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| Latin | Abundance |
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| Lemmus sibiricus | rare |
| Dicrostonyx torquatus | common |
| Microtus middendorffi | common |
| Microtus gregalis | common |
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Summary
of fauna studies: |
| Most bird species were counted on plots and in different habitats. Nesting biology and ecology of certain species were studied in detail (Red-throated Diver, Rough-legged Buzzard, Peregrine Falcon, Red-breasted Goose, Bewick's Swan, Petchora Pipit). Rodent trapping was continuously carried out from late May to early August using Gero snap-traps. |
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