期刊
CANADIAN JOURNAL OF ZOOLOGY
卷 99, 期 9, 页码 792-800出版社
CANADIAN SCIENCE PUBLISHING
DOI: 10.1139/cjz-2020-0191
关键词
Bald Eagles; Haliaeetus leucocephalus; Pacific salmonids; Oncorhynchus spp.; Ideal Free Distribution; resource patches; behavioural ecology; spatial distribution; scavengers; temporal distribution
类别
资金
- Hancock Wildlife Foundation
- MITACS
The movement of Bald Eagles in the Pacific Northwest is heavily influenced by the availability of post-spawning Pacific salmon carcasses during the non-breeding period. The study found that Bald Eagle abundance matched the seasonal progression of salmon carcass availability, with a positive but lower-than-expected relationship between eagle and salmon numbers.
The movement of individuals according to the availability of resources has a fundamental effect on animal distributions. In the Pacific Northwest, Bald Eagles (Haliaeetus leucocephalus (Linnaeus, 1766)) rely heavily on scavenging opportunities during the non-breeding period, and their distribution and movements are thought to be strongly influenced by the availability of post-spawning Pacific salmon (genus Oncorhynchus Suckley, 1861) carcasses. We surveyed the abundance of eagles and salmon on four adjacent rivers on Vancouver Island, British Columbia, Canada, during the 2017 fall spawning season. Salmon began to arrive in late September, peaked in abundance in mid-November, and were absent after early December. The seasonal progression of Bald Eagle abundance matched that of salmon carcass availability. The slope of proportional eagle-salmon relationship was significantly positive, though lower than the 1:1 match predicted by Ideal Free Distribution theory. The numerical response of Bald Eagles to salmon abundance was elevated on one of the rivers, potentially due to physical features such as sandbars and mudflats that increased the availability of carcasses and provided access points for eagles.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据