Avifaunal investigations
Williamson FL, Thompson MC, Hines JQ. 1966. Avifaunal investigations. Pages 437-480. In Wilimovsky NJ. Environment of the Cape Thompson Region, Alaska. US Atomic Energy Commission, Division of Technical Information. Oak Ridge, TN
(Author's abstract) 'Bird populations in the Cape Thompson area, northwestern Alaska, were studied during the spring and summer months of 1959 thorugh 1961 to determine species composition, ecological distribution, density, productivity, and seasonal movements. One hundred and twenty species were recorded. and evidence of breeding was obtained for 65 of these. Twelve ecological formations based on characteristics of vegetation and physical features of the environment were used to analyze the distribution of birds. The density of breeding birds ranged from a low of 24 pairs per 100 acres in marshy Carex meadow to 194 pairs per 100 acres in riparian willow. the densities in open habitats were not unlike those observed in similar situations in temperate climates. Nest success of altricial birds building open nests was 43%, only slightly less than the 49% success recorded from a large number of studies at lower latitudes. Birds nesting in the Cape Thompson area rear a single brood each year; a few of the common respolls attempt a second nesting. Passerine birds have larger clutches than the same or related species in temperate areas, and this compensates to some extent for the failure of these species to produce a second brood. Birds arrive suddently in spring, and many species are already paired when they arrive. The onset of nesting is rapid, and considerable synchrony is manifest in the breeding and molt programs.'
- Type
- Book Chapter
- Authors
- Williamson, Francis; Thompson, Max; Hines, John
- Units
- ARCN , BELA , CAKR
- Keywords
- Abundance, altricial, Animal Studies, Arctic, Avian Community, Birds, Breeding, Cape Krusentern National Monument, Cape Thompson, Distribution, Ecological distribution, Habitat, Intermontane Plateaus, Migration, Nest Site Selection, Nesting, Passerine, Populations, Productivity, Riparian, Seasonal Movements, SNP, Species Composition, Western