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RESPONDENT
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Vladimir Morozov
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SITE NAME
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East of Bolshezemelskaya tundra and Polar Urals, Russia
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| Contact details
(phone/fax//e-mail//address): |
| (495)1553044 // piskulka@mtu-net.ru // Shebashevski Proezd, 7-16, Moscow, 125315, 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: |
According to reports of local people low amount of snow accumulated during the winter. Day-time temperatures rised above freezing on 9 May and reached +19øC on 19 May after a rapid warming on 16 May. Weather became cool afterwards, and heavy rains were frequent. Low snow reserves and warm wet weather in May resulted in rapid snowmelt, while flood on 20-25 May was high but not prolonged. Tundra surface was 95% free from snow by early June. Pronounced cooling on 1-3 June was followed by abundant snowfalls and negative temperatures even at day-time. Snow layer was 8-10 cm thick, which along with low temperatures and strong northerly winds resulted in perishing of passerine birds, including Bluethroats and Little Buntings. Very warm sunny weather established from 4-13 June, when air temperatures were above freezzing at night and reached +13-17øC at day-time. However another cooling occurred from 14-19 June, when air temperatures did not rise above freezing during day and dropped to -8øC at night. Strong north-western winds and snowfalls or rains with snow occurred during the whole period; the snowfalls being particularly heavy on 14-16 June, when snow layer up to 8 cm thick retained also during day-time. Snow line descended to 300 m asl in the mountains, and snow has started to melt only on 22 June there.
Summer weather was close to average, although pronounced cooling on 6-8 July was associated with dropping of temperatures to -2øC at night and +3-4øC during day due to daily long-lasting cold rains turning into snowfalls at night. A snow layer up to 5-7 cm thick established during night and melted only in the second half of the day.
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| Season temperature: |
average
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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: |
low
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Breeding conditions:
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Arctic Foxes, Red Foxes and Ermines were not recorded, and numbers of other mammalian predators were very low.
Snowy Owls were not recorded, while a wandering Short-eared Owl was seen once. Rough-legged Buzzards nests at a low density, particularly in the mountains, and a portion of birds maintaining territories during June and cancelling breeding was considerable. Clutch size normally did not exceed 3 eggs, and a single nest among surveyed contained 4 eggs. Most breeding pairs of buzzards managed to raise 2 chicks, and productivity in the mountains was slightly higher than on tundra plains. Nesting density of the Northern Harrier was low, clutch size did not exceed 4 eggs and broods mostly contained 3 chicks, which diet primarily consisted from birds. Long-tailed Skuas nested at a low density, and were observed depredation of their clutches by gulls and corvids.
Most species of waders occurred in the beginning of the breeding season in typical for southern tundra numbers, with the exception of Temminck's Stint and Jacksnipe which were less abundant than in previous years. Most waders arrived earlier due to early spring. Early arriving species (Wood Sandpiper, Ruff, Common Snipe, Whimbrel) had started nesting earlier than normal, but the periods of cold weather from 1-3 and from 14-19 June coincided with egg-laying in these species and many clutches were deserted. We found deserted clutches of Ruffs and Wood Sandpipers between two periods of cold weather. Common Snipes became considerably less common after the second cooling in mid June, and presumably most of these birds also deserted clutches. Eurasian Golden Plovers and Whimbles apparently did not suffer from adverse weather, while its concequencies for birds in the mountains were catastrophic. Presumably all clutches of Rock Ptarmigans and Dotterels perished, as we did not find nests or broods of these species, while Ptarmigans occurred in mixed flocks of males and females during the whole summer.
The last cooling on 6-8 July turned reporduction of many wader species into completely unsuccessful, coinciding with hatching of chicks. While dead chicks were not found, numbers of alarming birds decreased considerably after 8 July, and many waders (Wood Sandpiper, phalaropes, plovers) have started to gather in flocks. Not a single brood or juvenile were seen in Ruff and Common Snipe. Broods of ducks and Willow Ptarmigans were also fairly rare.
Predation pressure by mammalian predators on clutches and chicks of waders was very small, while avian predators considerably affected reproductive performance of birds. Avian predators not only destroyed clutches of small birds, but also of other predators. thus, wandering Rough-legged Buzzards and Common Crows destroyed nests of Long-tailed Skuas and one of the nests of Northern Harriers on the survey plot. Herring Gulls (Larus heuglini) destoyed nests of skuas and Common Gulls, while wandering Long-tailed Skuas destroyed nests of Common Gulls, and vise versa. However, the combined impact of predation by uncommon avian predators on reproduction was much lower compared with the impact of adverse weather conditions.
Reproductive success was low or very low in most species of waders, while the Ruff and Common Snipe were complete fail-breeders.
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Rodent dynamics:
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| Numbers of lemmings and vole were considerable in the end of winter and early spring, based on the numbers of undersnow nests, but rodent abundance decreased dramatically by early June and remained low during summer. Collared Lemmings were seen twice in the Polar Urals mountains, while Siberian Lemmings were not recorded during 2.5 months of field works. Vole, primarily Narrow-skulled, were very rare, although their abundance increased slightly by the end of summer.
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Rodent species recorded:
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| Latin | Abundance |
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| Dicrostonyx torquatus | rare |
| Microtus gregalis | rare |
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Summary
of fauna studies: |
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