Author: T. Lee Tibbitts Publisher: ISBN: Category : Bird surveys Languages : en Pages : 0
Book Description
Aerial and ground-based surveys were conducted in intertidal habitats of Izembek National Wildlife Refuge, Alaska, between July and October 1993, to assess the refuge's importance as a shorebird staging area. Surveys of less intensive nature had been conducted in winter (November 1993, February 1994) and spring (May 1994) to characterize the shorebird population in these seasons. Of the 31 species of shorebirds known to occur on the refuge in autumn, 28 were recorded. The size of the staging population is estimated to be between 78,000 and 285,000 birds. Rock sandpiper, dunlin, and western sandpiper accounted for over 95% of all birds recorded on aerial surveys. The wintering population consisted of about 9,000 individuals of two species, rock sandpiper and sanderling. These data qualify the refuge for inclusion in the Western Hemisphere Shorebird Reserve Network. Shorebird distribution varied both temporally and among species. In early autumn, the majority of shorebirds foraged on intertidal flats and roosted on sea beaches in the northeast portion of Izembek Lagoon, whereas, in late autumn most birds used intertidal flats in Moffet Lagoon. In late winter, birds were present only in ice-free areas near lagoon entrances. Rock sandpipers were more likely than dunlins to be found on Bering Sea beaches, and dunlins were more prevalent than rock sandpipers in Moffet Lagoon.
Author: Dirk V. Derksen Publisher: ISBN: Category : Birds Languages : en Pages : 36
Book Description
Distribution, abundance, and use of wetland habitats by migratory birds were studied at 2 interior and 3 outer Arctic Coastal Plain sites in the National Petroleum Reserve in Alaska in 1977 and 1978.
Author: Dirk V. Derksen Publisher: ISBN: Category : Languages : en Pages : 31
Book Description
Distribution, abundance and use of wetland habitats by migratory birds were studied at two interior and three outer Arctic Coastal Plain sites in the National Petroleum Reserve in Alaska (NPR-A) in 1977 and 1978.
Author: Karen S. Bollinger Publisher: ISBN: Category : Aerial surveys Languages : en Pages : 17
Book Description
An aerial survey was conducted along the coastlines and adjacent estuaries of Izembek National Wildlife Refuge and the Sanak Islands in Feburary 27 to March 1, 2011 in order to determine winter distribution, abundance, population trend, and habitat use of Pacific brant. This survey in a component of the annual Pacific Flyway mid-winter index. The survey focused on three main species: Pacific brant, emperor goose, and Steller's eider, and population trends are given for 1980 to 2011. Other birds (primarily water birds) and mammals observed during the survey are recorded and compared to earlier counts in 1970, 1991, and 2010.
Author: Stephen Michael Murphy Publisher: ISBN: Category : Habitat selection Languages : en Pages : 81
Book Description
This study examines the phenology, species composition, relative abundance, patterns of habitat use, and resource partitioning by migrating and breeding shorebirds on the eastern Copper River Delta. The peak of spring migration in 1978 occurred on 11 May, several days later than normal. Interspecific competition for foraging space on intertidal mudflats was minimized by temporal differences in the peaks of migration of the most abundant species and by spatial segregation during feeding. Fall migration differed from spring migration in several ways: 1) different species composition, 2) lower densities of staging birds, 3) different patterns of habitat use, and 4) less habitat segregation between species. Forty-five nests of six species of shorebirds were located along 52 km of transects. The peak of nest initiation was between 25 May and 31 May. Over 75% of the nests occurred in three habitat types, all of which were dominated by varying degrees of sedge, grass, and moss.
Author: T. Lee Tibbitts
Author: Dirk V. Derksen
Author: Dirk V. Derksen
Author: Karen S. Bollinger
Author: Robert M. Platte
Author: Patrick J. Gould
Author: Winifred B. Sidle
Author: Robert E. Gill (Jr.)
Author: Stephen Michael Murphy
Author: Robert E. Gill