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RESPONDENT
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Richard Anthony
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SITE NAME
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Yukon-Kuskokwim outer Delta south-west, Alaska, USA
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| Contact
details (phone/fax//e-mail//address): |
| (907)786-3508/(907)786-3636(f) // mike_Anthony@usgs.gov // Alaska Science Center, USGS, Biological Science Office, 1011 East Tudor Road, Anchorage, AK 99503, USA |
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PROJECT DETAILS
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Project name:
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Aerial video surveys of Brant colonies on Yukon-Kuskokwim delta |
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Start of survey:
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End
of survey:
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Team
size:
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WEATHER CONDITIONS
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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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| Aerial surveys using video strip transects were conducted during mid-incubation at five localities of the delta south-west (Tutakoke River, Kokechik Bay, Kigigak Island, Baird Inlet Island and Baird Inlet Peninsula). Total estimated population of Brent Geese breeding in 2001 was the lowest since 1993. Based on observations of empty nest bowls and tracks in mud near nest, I assume that Arctic Foxes were the primary predator of Brant nests this year. This is consistent with observations of a permanent field crew at the Tutakoke River Brant colony and general observations by field crews working in the central portion of the Yukon-Kuskowkim Delta. Baird Inlet Island was heavily egged by humans in 2001 (estimated 500-800 eggs taken) but is very low, cut by numerous small sloughs, and has little cover for foxes. Kokechik Bay, which had better success than all colonies except Baird Inlet Island in 2001, is near three villages and, as a result, receives heavy hunting and trapping of foxes in winter and spring. At Kigigak Island, many Brant nest on islands in large lakes, which may reduce their vulnerablility to foxes; also because it is an island fewer foxes have access to the area than Tutakoke River and Baird Inlet Peninsula. Possible factors affecting productivity in past years have been flood tides during incubation at Baird Inlet Island and parts of Tutakoke River in 1997, egging by humans at Kokechik Bay and Baird Inlet Island in 1999, and the effects of El Nino (1997) on eelgrass in wintering areas, resulting in poorer condition of females nesting at all colonies in 1998. |
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Rodent dynamics:
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| Rare Tundra Voles were observed during ground-truthing; also talked with permanent field persons at site.
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Rodent species recorded:
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| Latin | Abundance |
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| Microtus oeconomus | rare |
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Summary
of fauna studies: |
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