Abstract
I studied costs of nest defense in Azure-winged Magpies Cyanopica cyana in Tokyo, Japan in 1994 and 1995. I compared time devoted to nest defense, frequency of nestling feeding, and number of fledglings of magpies breeding near nests of Japanese Lesser Sparrowhawk Accipiter gularis and magpies breeding far from such nests. Because the hawks attack potential predators, magpies near a hawk's nest did not defend their nest, whereas magpies breeding far from a hawk's nest defended their nest. Feeding frequencies and number of fledglings were greater near a hawk's nest than far from it. Because nest defense incurs a cost in the form of decreased feeding time, Azure-winged Magpies far from a hawk's nest probably provided less food to their chicks and therefore raised fewer fledglings than those breeding close to a hawk.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.