Social context affects risk taking by a satellite species in a mixed-species foraging group
Social context affects risk taking by a satellite species in a mixed-species foraging group
复制标题
DOI：
10.1093/beheco/11.1.110
复制
发表时间：
2000-01-01
影响因子：
2.4
通讯作者：
Grubb, TC
中科院分区：
文献类型：
--
作者：
Dolby, AS;Grubb, TC
冬季，在北美东部的落叶林中，混合种类的鸟群形成。这些鸟群包括两个群居的核心物种，丛山雀（Baeolophus bicolor）和卡罗莱纳山雀（Poecile carolinensis），以及一些追随者或卫星物种，包括绒毛啄木鸟（Picoides pubescens）和白胸雀（Sitta carolinensis）。解释参与这种混合物种觅食群体的适应性的假说集中在增加觅食成功率和/或降低捕食风险上。我们测试了这样一种预测，即如果猫雀加入核物种以降低捕食风险，它们应该更不愿意在没有山雀的情况下访问暴露的喂食器，而不是在山雀存在的情况下。当喂食器位于距离森林覆盖16 m处时，当山雀不存在时，雄性和雌性nuchches访问喂食器的潜伏期都更大。去除山雀对8 m潜伏期无影响。在没有山雀的情况下，在两个距离上，nuchches访问喂食器的频率都较低。这些结果表明，降低被捕食的风险是卫星物种通过与核物种聚集而获得的好处。
Mixed-species flocks of birds form during winter in the eastern deciduous forests of North America. These flocks consist of two flock-leading nuclear species, tufted titmouse (Baeolophus bicolor) and Carolina chickadee (Poecile carolinensis), and several follower, or satellite, species, including downy woodpecker (Picoides pubescens) and white-breasted nuthatch (Sitta carolinensis). Hypotheses explaining the adaptiveness of participation in such mixed-species foraging groups have focused on increased foraging success and/or decreased predation risk. We tested the prediction that if nuthatches join nuclear species to reduce predation risk, they should be more reluctant to visit an exposed feeder in the absence of titmice than in their presence. When the feeder was positioned 16 m from forest cover, latency to visit the feeder was greater for both male and female nuthatches when titmice were absent. Removal of titmice had no effect on latency at 8 m. In the absence of titmice, nuthatches visited the feeder less frequently at both distances. These results indicate that reduced predation risk is a benefit that satellite species gain by flocking with nuclear species.