| Communal roosting of common ravens in southwestern Idaho.: An article from: Wilson Bulletin |  | Authors: Kathleen A. Engel, Leonard S. Young, Karen Steenhof, Jerry A. Roppe, Michael N. Kochert
Brand: The Gale Group
Category: Book
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Media: Digital
Pages: 18
ASIN: B00091Y5CO
Publication Date: March 1, 1992
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Product Description
This digital document is an article from Wilson Bulletin, published by Wilson Ornithological Society on March 1, 1992. The length of the article is 5236 words. The page length shown above is based on a typical 300-word page. The article is delivered in HTML format and is available in your Amazon.com Digital Locker immediately after purchase. You can view it with any web browser.
From the author: From 1983-1987, Common Ravens (Corvus corax) used thirteen communal roosts on a segment of electrical transmission line that runs 597 km from south-central Idaho to south-central Oregon. Up to 2103 ravens were counted at a single roost that spanned approximately six km of transmission line and 15 transmission towers. Most roosts were occupied between spring and autumn; one was occupied year-round. Peak numbers of ravens at most roosts and peak numbers of occupied roosts occurred during late summer and early autumn. Ravens concentrated on the highest portions of transmission towers, although more ravens roosted on the lower portions of towers when winds exceeded seven km/h. Ravens arrived at roosts earlier relative to sunset during summer than during spring or fall. Soon after fledging, juvenile and adult ravens left nesting areas and moved as far as 60 km to communal roosts. Some ravens used more than one communal roost during a year, moving between roosts up to 63 km apart. Received 19 Feb. 1991, accepted 10 July 1991.
From the supplier: Large numbers of Common Ravens (Corvus corax) roosted at 13 sites on a segment of a 597 kilometer power transmission line in southwestern Idaho and southeastern Oregon between 1983 and 1987. This was the largest known communal roosting site on a man-made structure. At one point, a communal roosting site of around six kilometers of line and 15 transmission towers accommodated up to 2,013 ravens. The phenomenon is attributed to the power line's proximity to abundant food supply and nesting sites, and its affording more safety from predators than traditional roosting sites.
Citation Details
Title: Communal roosting of common ravens in southwestern Idaho.
Author: Kathleen A. Engel
Publication: Wilson Bulletin (Refereed)
Date: March 1, 1992
Publisher: Wilson Ornithological Society
Volume: v104 Issue: n1 Page: p105(17)
Distributed by Thomson Gale
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