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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The status of the common crow Corvus brachyrhynchos brehm in the Great Basin

Richards, Gerald Low 01 August 1967 (has links)
Due to a lack of taxonomic and distributional information concerning the Common Crow Corvus brachryhynchos Brehm inhabiting the Great Basin of North America, Johnston (1961) in one of the most recent revisions on crows, was unable to include this area in his work. Between 1965 and 1967, field trips were taken throughout the Great Basin to secure specims, and to determine to what extent the area was being utilized by crows. Ecological information such as habitat prference, nesting behavior, and interactions with other species was collected where possible. Forty-eight birds were collected from the Great Basin. From a comparison of data from these birds with data from crows from other areas of North America, it was concluded that the Great Basin crows are the eastern variety Corvus brachyrhynchos brachyrhynchos Brehm. Summer and winter distribution is similar in that river valleys with meandering streams, which support willow thickets and nearby meadows, are primarily utilized. A difference in winter distribution with that of the summer is the occurrence of large concentrations of crows in Utah during the winter. Crows were found to have interactions with magpies and starlings. These consisted mainly of crows utilizing unfinished magpie nets, and stealing food scraps from starlings. The crow causes very little damage to crops in the Great Basin and is probably an asset because of the recreation it affords the local sportsmen, rather than an economic problem.

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