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RESPONDENT
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Mikhail Golovatin
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SITE NAME
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Voikar River middle reaches, Lower Ob' River area, Russia
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| Contact details
(phone/fax//e-mail//address): |
| (34992)5-69-10(off.)/5-71-85(fax) // golovatin@ipae.uran.ru // Inst. of Plant and Animal Ecology, 8 Marta St, 202, Ekaterinburg, 620144, 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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6.05
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12.06
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WEATHER
CONDITIONS
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Weather conditions: |
| Low amount of snow was accumulated, and snow melted quickly after warming in late April. However, spring was cold afterwards. Night frost were frequent in May, and slush and ice were forming on river surface in mid May. Ice broke early - on 4 May on the Voikar River, and on 17 May on the Ob' River. Rain or snow occurred regularily. Despite early snow melt and appearance of buds stimulated by warming in April, further development of vegetation was retarded by cold weather until 10 June (birch greening). Summer was also cold and wet. Ice on tundra lakes retained for a long time due to low amount of melting water.
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| Date of 50%
snow-cover: |
28.04-1.05
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| Date of ice-break on
rivers: |
4.05
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| Date of final loss of
snow: |
20-25.05
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BIOTIC
CONDITIONS
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| Rodents abundance evaluation: |
high
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Breeding conditions:
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Abundant Ground Voles attracted many predators: Red Foxes, crows and gulls. Even Greater Spotted Eagles were recorded, although they do not normally breed in the area. Overfeeded predators, including dogs in settlments, stopped reacting at each vole taking only rodents in close proximity. Many dead voles were consumed partially, or had just damaged head or thorax. Abundance of other vole species outside the floodplain attracted mustelids and owls. Short-eared Owls nested in tundra at a very high density (about 1 pair/sq.km). Numbers of nesting Arctic Terns decreased noticably, but numbers of Common Gulls were usual. Willow Ptarmigans were somewhat more abundant than normal.
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Rodent dynamics:
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| Ground Voles appeared in floodplain areas in outstanding numbers. Voles were numerous on shores of lakes and channels, in grass and on forested patches. They destroyed all seedlings in greenhouses in settlements, visited buildings and were common on streets. In the beginning of summer Ground Voles started to swim across Ob' River and other large waterbodies in a lemming-like manner, perishing in mass. Numerous bodies were observed on river banks and floating in the water. Many voles demonstrated signs of megrim-like desease, hovering and dieing. Microtus sp. and Clethrionomys sp. voles were abundant outside floodplain.
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Rodent species recorded:
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| Latin | Abundance |
| Arvicola terrestris | abundant |
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Summary
of fauna studies: |
| Bird counts on the plot were carried out, along with descriptions of nests, spatial distribution and behaviour.
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