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SITE NAME
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Churchill, Manitoba, Canada
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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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AMERICAN GOLDEN-PLOVER (PLUVIALIS DOMINICA) DEMOGRAPHY AND BEHAVIOUR
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Start of survey:
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End
of survey: |
Team
size: |
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7.06
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17.07
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1
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WEATHER
CONDITIONS
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Weather conditions: |
| The spring of the 2001 was very early, and the above-average temperatures prevailed for most of the period from the beginning of May to October. Snow disappeared long before my arrival (June 7), and the break-up on the Churchill River occurred in the last days of May - one of the earliest dates remembered by the local residents. Atypically high temperatures reaching 30øC were recorded in the last days of May and the first days of June. This was followed by the more seasonably weather (average June to early July), with a short-lasting snow cover on June 26, and close to freezing temperatures in first days of July - not atypical for this place.
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| Date of ice-break on
rivers: |
end May
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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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Several dens of an Arctic Fox were active in the area, and the Arctic Skuas and Herring Gulls bred in regular numbers in the same areas. Known to me territories of Rough-legged Hawk, Merlin, and Northern Harrier were vacant, but the birds of two latter species were occasionally seen in the area.
There were usual numbers of geese and they were doing well (clutches didn't seem to be smaller than usual and fledging success appeared to be good, too - tremendous difference with the last year, when we saw large goslings very rarely, and usually only 1 or 2 of them with parents). Spring hunting was allowed (and encouraged) in order to reduce numbers of geese that are devastating habitat in the nearby colony at La Perouse Bay, and to a lesser extend also at Churchill. However, this pressure didn't diminish numbers of nesting pairs in any substantial way, if at all. Breeding of Tundra Swans, Sandhill Cranes, and Little Gulls was confirmed - these species are known to breed in some years, but in the other years their status remain unclear. Cranes were common as non-breeders, and very rare as breeding birds - I knew only 1 pair.
American Golden Plovers nested in lower numbers than the last year: in the area of about 12 km2, where in the 2000 18 nests were found, in the 2001 only 9 were known. Lesser Yellowlegs also nested in the lower numbers than last year. Conversely, Killdeers and Whimbrels, which bred in very low numbers last year, bred in 2001 in the highest numbers in the last 3 years. High numbers of the Whimbrels coincided with the high abundance of the last-year berries still present in the spring, and the birds were often seen feeding on these berries. Although no formal surveys of Short-billed Dowitcher were done, unusually many nests were found by chance. Lapland Bunting - one of the commonest Passerines in at least last six decades did not breed for the first time (there were still two pairs last year), and only one pair of Smith's Longspur Calcarius pictus - also a common breeder in the past, was seen.
Onset of nesting was very early, and so the hatching dates were the earliest on record for several species (Short-billed Dowitcher: 17 June, American Golden-Plover and Hudsonian Godwit: 26 June). For comparison: last year's last hatching of Golden-Plover anticipated on 20 July belonged to the latest reported.
Nesting success was recorded only for Golden-Plovers, where all of 11 nests which fate was known hatched successfully. This was the highest hatching success on record for this species. Hatching occurred in the span of 13 days (26 June - 8 July), thus synchrony was similar to the other warm season of 1999, and was lower than in the cold year of 2000, when all nests hatched within 7 days. The mean hatching date was 2 July, and the distribution was approximately normal. Clutch size was typical for this place (3.93).
As lemmings are never plentiful in the area, even during the 'best' years (Erica Nol, pers.comm.), high nest success of waders in a year of very low rodent numbers can be related to specialization of Arctic Foxes and Arctic Skuas on other abundant prey (geese eggs and passerines, respectively).
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Rodent dynamics:
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| This was the second year of the very low lemming numbers; no lemmings were caught neither at Churchill nor 50 km farther south (J. DuBois, Manitoba Museum of Man and Nature, Winnipeg, pers. comm.), and no lemmings were seen during field work.
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Rodent species recorded:
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| Latin | Abundance |
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| Dicrostonyx groenlandicus | rare |
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Summary
of fauna studies: |
| This was the second year of population study on American Golden-Plovers (Pluvialis dominica).
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