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Weather conditions: |
At arrival on 11 June snow was present on 30% of flat open surface and completely melted on 16 June (but on 25 June in the forest)/ Ice broke on 16 June on the Fomich River. Weather conditions were clearly atypical in 2006/ Spring was cold and prolonged; air temperature rarely exceeded +7øC before 6 July and dropped below freezing on soil on several occasions. Ice on lakes broke on 11 July due to strong wind. Very hot weather with day-time temperatures exceeding +25-28øC and maximal value +32.8øC on 24 July prevailed in the second half of July. Distant forest fires caused dense gauze in the air and low visibility during this period. Precipitation reached 26 mm during the night on 3 August, and increased water level on all rivers and springs could have caused mortality of broods of Eurasian Golden Plovers in the valleys (at least, there density approximately halved after 3 August). In August weather was generally typical for this period, but temperature dropped 20øC during 12 hours on 17-18 August, which was followed by hurricane wind reaching 25 m/s.The lowest daily mean temperature (+2.5øC) was recorded on 18 August which was followed by phenological autumn with complete yellowing of shrub leaves and start of larch yellowing. Precipitation occurred frequently, by in low amount (except for the 3 August event). Except for 17-18 August strong wind occurred on 3 days, mostly in spring.
Thus, spring was cold, summer generally hot and short, while autumn early and cold. The whole season was quite rainly, except for the dry early summer period.
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| Rodents abundance evaluation: |
average
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Breeding conditions:
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Study area was mostly represented by a plateau 300-320 m asl, formed by Cambrian limestone. Vegetation is extremely sparse, and rarely exceeds 10%, except for the depressions where shrub-dryas-moss-sedge tubdra can reach up to 70% of the coverage. Sparse larch forest was found in the inter-mountain valleys.
Arctic Foxes were rare, and a single animal was seen in spring, but tracks of Arctic Foxes and Wolves were regularly recorded in the Fomich River floodplain. Afanasievskiye Lakes area was visited by a Brown Bear. Spring migration of Reindeers terminated by 20 June, while autumn migration started from 15 August. Reindeers were mostly migrating farther eastward and relatively small numbers. Among avian predators Long-tailed Skua was relatively common in the area, which was also inhabited by several pairs of Herring Gulls. Other predators were extremely rare, and a single nest of 28 monitored was destroyed (a nest of Black-throated Diver, established during high water period, and separated by a distance of 100 m from water after the latter retreated).
Non-breeding territorial Rough-legged Buzzards were common, but a single nest with 3 chicks was found. A single chick of 3 survived in a found nest fo Merlin, while both chicks fledged from a nest of Gyrfalcon, and all 3 found nests of Herring Gulls produced 3 chicks each. Birds of prey can, probably, be abundant in the area in favourable seasons, as numerous nests were found on rocks, apparently inhabited recently.
Bird migration was not intensive in the area, but diversity of species was relatively high. Dusky Thrushes had incomplete clutch of 2 eggs on 24 June. Lekking behaviour was observed until 25 June in Ruffs, and up to 25 males were visiting one of the hillocks in the bog. Hatching occurred on 22 July in Long-tailed Duck, 12 July in Merlin, 18 July in Rock Ptarmigan, 20 July in Eurasian Golden Plover, 11 July in Ruff, 20 July in Bar-tailed Godwit, 16 July in Herring Gull, 11 July in Arctic Tern, 2 July in Shorelark and Lapland Bunting, 4 July in Redpoll, 6 July in Little Bunting. All these dates were approximately one week delayed compared to average for the area observed in 2003 in the middle reaches of the Fomich River. Fledging occurred on 10 July in Gyrfalcon, 27 July in Rock Ptarmigan, 15 August in Eurasian Golden Plover, 9 August in Ruff, 14 August in Arctic Tern, 10 July in White Wagtail and Redpoll (first wave of breeding in the latter species), 11 July in Lapland Bunting and 18 July in Little Bunting. A delay in fledging dates of non-passerine birds was less pronounced compared with delay in hatching dates.
Breeding success can be evaluated as average in most species of birds, although information on fledging success is scarce. Lapland Buntings and Redpolls raised to fledging 2-3 of 6-7 and 1-2 of 4-6 hatched chicks, respectively. Alarming near broods Bar-tailed Godwit were common before 10 August, but disappeared after this date.
In total 55 species of birds were recorded in the area, including 38 breeding or probably breeding species. Most birds occurred in the intermountain basins, while wide areas of limestone plateaus were extremely poor in bird diversity and numbers. Pacific Golden Plover and Dotterel inhabited plateaus during the whole season at a very low density, while Snow Bunting, Wheatear and White Wagtail deserted these habitats after fledging. Lapland Bunting and locally Eurasian Golden Plover and Arctic Tern were a few numeous species. A relative commonness on breeding of such tundra species as Red-necked Phalarope, Long-tailed Duck, Long-tailed Skua and Rock Ptarmigan was difficult to expect, given commonness of southern tundra and forest tundra species (White-winged Scoter, Wigeon, Dusky Thrush, Little Bunting and Red-breasted Merganser). Red-breasted Mergansers were not observed neither on migration, nor as breeders, but many broods of this species appeared since mid August on Afanasievsiye Lakes, presumably having been arrived from the Eriechka River basin along the Afanasievskaya channel. Bean Goose, Teal, Willow Grouse, Wood Sandpiper and Ringed Plover inhabited mostly forested vallyes of the Fomich and Eriechka rivers. Three broods of Grey-tailed Tattlers per 8 km of the Kamenistaya River valley were recorded 15 km southward of the main study area.
Noteworthy observations include a Bewick's Swan pair which inhabited the earstern-most of Afanasievskiye Lakes during the whole season, and repeated records of an alarming Curlew Sandpiper female near small hillock bog, indicating probable breeding. Adult and juvenile Little Gulls were recorded in mid August. White-fronted Goose and Red-throated Diver were recorded only on autumn migration, while numbers of Temminck's and Little stints were higher in autumn compared with spring. A prevailing direction of autumn migration was westward.
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