当鸬鹚捕鱼时：捕食定居性和活动性猎物的不同成本
When cormorants go fishing: the differing costs of hunting for sedentary and motile prey.
作者信息
Halsey Lewis G, White Craig R, Enstipp Manfred R, Jones David R, Martin Graham R, Butler Patrick J
机构信息
Centre for Ornithology, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
出版信息
Biol Lett. 2007 Oct 22;3(5):574-6. doi: 10.1098/rsbl.2007.0121.
Cormorants hunt both benthic (sedentary) and pelagic (motile) prey but it is not known if the energy costs of foraging on these prey differ. We used respirometry to measure the costs of diving in double-crested cormorants (Phalacrocorax auritus) foraging either for sedentary (fish pieces) or motile (juvenile salmon) prey in a deep dive tank. Short dives for sedentary prey were more expensive than dives of similar duration for motile prey (e.g. 20% higher for a 10s dive) whereas the reverse was true for long dives (i.e. long dives for motile prey were more expensive than for sedentary prey). Across dives of all durations, the foraging phase of the dive was more expensive when the birds hunted motile prey, presumably due to pursuit costs. The period of descent in all the dives undertaken appears to have been more expensive when the birds foraged on sedentary prey, probably due to a higher swimming speed during this period.
鸬鹚捕食底栖（定居性）和远洋（游动性）猎物，但尚不清楚捕食这些猎物的能量消耗是否存在差异。我们使用呼吸测量法来测量双冠鸬鹚（Phalacrocorax auritus）在深潜池中捕食定居性猎物（鱼片）或游动性猎物（幼鲑）时的潜水成本。捕食定居性猎物的短时间潜水比捕食游动性猎物的类似时长潜水成本更高（例如，10秒潜水高出20%），而长时间潜水则相反（即捕食游动性猎物的长时间潜水比捕食定居性猎物的成本更高）。在所有时长的潜水中，当鸟类捕食游动性猎物时，潜水的觅食阶段成本更高，这可能是由于追捕成本。当鸟类捕食定居性猎物时，所有潜水的下降阶段似乎成本更高，这可能是由于在此期间游泳速度更快。
Zotero 插件