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SITE NAME
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St. George Island, Northwest, Alaska, USA
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| Contact details
(phone/fax//e-mail//address): |
| + 585 256 0842/+ 585 256 0842(fax) // jokli@FRONTIERNET.NET // 410 Linden St, Rochester, NY 14620-2442, USA
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PROJECT DETAILS |
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Project name:
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Breeding behavior of the Rock Sandpiper (Calidris ptilocnemis)
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Start of survey:
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End
of survey: |
Team
size: |
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17.06
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31.08
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1
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WEATHER
CONDITIONS
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Weather conditions: |
| According to the local residents, the winter 2002/03 was unusually mild and virtually snowless, it was followed by the mildest spring since 1999 - the earliest year for which the NOAA data is available on-line: in April there were only 3 days with the mean temperature below freezing, and 10 days with min temperature below freezing, in May there were 0 and 3 respective days. For comparison, in 1999 - one of the coldest springs during the past 5 years there were 19 and 22 respective days in April, and 5 and 13 in May (www.ncdc.noaa.gov). Thus, time of snow melt presumably did not affect directly onset of laying of ground-nesting birds.
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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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On my arrival the Rock Sandpipers (Calidris ptilocnemis) - basically the only nesting shorebirds - were in all stages of nesting cycle, from pre-laying to rearing well-feathered chicks. Hatching was prolonged, as previously reported from this locality, and spanned about 55 days. It is not known whether the latest clutches were the original ones, replacements or the second broods (after successful fledging of the first one); no reduction of clutch size - often assumed to characterise re-nesting - was seen among the latest clutches (mean size was 4.0).
The ground nesting birds and specifically shorebirds, represented chiefly by the Rock Sandpiper (Calidris ptilocnemis) (besides it only one brood of the Least Sandpiper (C. minutilla) was found) were most likely affected by the presence of the following species. Several Snowy Owls (Nyctea scandiaca) were seen on daily basis throughout the season, nesting of this species was not confirmed. Several Long-tailed Skuas (Stercorarius longicaudus) were seen searching for food over the tundra all over the Island; they were present only during several consecutive days in the first week of July. Up to three Common Ravens (Corvus corax) were simultaneously seen on multiple occasions throughout the season, breeding seems likely, but was not confirmed. Presence of predatory gulls, represented chiefly by Glaucous-winged Gulls (Larus glaucescens) was limited to the coast and they were never seen hunting over the tundra. Arctic foxes (Alopex lagopus) were plentiful around the Village, seabirds colonies (cliffs and Least Auklet colony on slopes of Ulakaia) and rookeries, however tundra - with the exception of the area between the Village, Ulakaia and the nearest rookery - was generally fox-free. Considering localized distribution of foxes and abundance of other food (marine birds, dead seal pups, caribou carcass, urchins etc.), both lemmings and shorebirds are not likely an important fox food during summer. Both might, however, be sought by other shorebird egg and chick predators like skuas, ravens and owls.
Black- and Red-legged kittiwakes (Rissa tridactila and R. brevirostris), Common and Thick-billed murres (Uria aalge and U. lomvia) and Least Auklets (Aethia pusilla) were systematically prayed upon by Arctic foxes. Breeding success of Black-legged Kittiwakes - the only colonial species I focused on - differed in various parts of the Island from almost total failure to the relatively high success, as indicated by the fraction of two-chick broods among fledged and nearly fledged broods. These differences in success were presumed to depend on food availability.
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Rodent dynamics:
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| Brown lemmings (Lemmus sibiricus) - the only rodent inhabiting the Island - were present, their numbers seemed to be low. I didn't see any, but 2 were seen by others and 1 road kill was found.
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Rodent species recorded:
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| Latin | Abundance |
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| Lemmus sibiricus | rare |
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Summary
of fauna studies: |
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