You are here: Home
/ Publication Information
Title: Rejection of cowbird eggs by crissal thrashers
Author: Finch, Deborah M.
Source: The Auk. 99: 719-724.
Publication Series: Not categorized
Description: Although the "dwarf" race of the Brown-headed Cowbird (Molothrus ater obscurus) is sympatric with the Crissal Thrasher (Toxostoma dorsale) in the lower Colorado River valley, I observed no parasitism in 15 thrasher nests. To determine whether or not the absence of cowbird eggs was caused by egg rejection, I experimentally parasitized nine thrasher nests. Cowbird eggs were ejected by thrashers at all experimental nests. To test the prediction that ejection or absence of cowbird eggs reduces nesting mortality, I compared thrasher nesting success to that of a sympatric accepter, the Abert's Towhee (Pipilo aberti).
Keywords: Brown-headed Cowbird, Molothrus ater obscurus, Crissal Thrasher, Toxostoma dorsale, Abert's Towhee, Pipilo aberti, egg rejection
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
XML: View XML
Finch, Deborah M. 1982. Rejection of cowbird eggs by crissal thrashers. The Auk. 99: 719-724.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility