Skip Navigation


Behavioral Ecology Advance Access originally published online on November 17, 2004
Behavioral Ecology 2005 16(2):327-334; doi:10.1093/beheco/arh166
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Lay Summary
Right arrow All Versions of this Article:
16/2/327    most recent
arh166v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (1)
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Speed, M. P.
Right arrow Articles by Ruxton, G. D.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Speed, M. P.
Right arrow Articles by Ruxton, G. D.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Behavioral Ecology vol. 16 no. 2 © International Society for Behavioral Ecology 2004; all rights reserved.

Countershading enhances crypsis with some bird species but not others

Michael P. Speeda,b,*, David J. Kellyb,c, Andrew M. Davidsonb and Graeme D. Ruxtond

a School of Biological Sciences, Liverpool University, Crown Street, Liverpool L69 7ZB, U.K., b Biology, Liverpool Hope University College, Childwall, Liverpool L16 9JD, U.K., c Department of Zoology, Trinity College Dublin, Dublin 2, Ireland, and d Institute of Biomedical and Life Sciences, Graham Kerr Building, University of Glasgow, Glasgow G12 8QQ, U.K.

* Address correspondence to M.P. Speed. E-mail: speedm{at}liv.ac.uk.

Although the theory of self-shadow concealing countershading is over a century old, there are very few direct empirical tests to substantiate the prediction that prey that are dorsally darkened and ventrally lightened (generally termed countershaded) suffer lower rates of attack than other prey. In this paper, we report experiments designed to determine whether artificial, countershaded prey are chosen by predators less often than those that are all light, all dark, or reverse shaded (i.e., dorsally lightened and ventrally darkened). Artificial prey were presented in gardens and parks to free-living birds, either on white backgrounds or on backgrounds with some degrees of color matching. In one experiment, birds were unmarked, and in the other, they were individually identifiable. We found that in three experimental trials, countershaded baits were attacked at a rate not significantly different from that of uniformly dark baits. In one experimental trial, countershaded baits were at some advantage. When we examined the data set for this trial more closely, it was apparent that blackbirds were taking countershaded baits least often, but blue tits and robins conferred no special advantage to countershaded baits. Hence, the efficacy of countershading may vary with species of predator.

Key words: countershading, crypsis, predator, prey.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.