Within-Year Survival of Nonbreeding Crested Caracaras

[摘要] Abstract. Many birds do not breed in the year(s) immediately following independence from parental care. Instead, they spend time as immatures attaining adult plumage and spend time as floaters searching for an opportunity to breed. Floaters are nonbreeding adults. Survival during this period often is poorly understood because immatures and floaters can be secretive and range widely, making them difficult to track. From July 2006 through March 2009, we used radio-tracking data collected by aerial telemetry to estimate survival of 58 nonbreeding Crested Caracaras (Caracara cheriway). Based on an information-theoretic approach, the best-supported models indicated differences in monthly survival, which was lowest (0.953) during the peak of breeding (December–January), slightly higher (0.984) during the remainder of the breeding season (October, November, February, March), and highest (0.995) during the nonbreeding season (April–September). We identified “life stage” as juvenile, immature, or floater on the ba...

[学科分类] 动物科学

[关键词] Caracara cheriway Crested Caracara;floater;immature;nonbreeding;prospecting;survival