Samhouri Jameal F, Vance Richard R, Forrester Graham E, Steele Mark A
Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095-1606, USA.
Oecologia. 2009 May;160(2):257-65. doi: 10.1007/s00442-009-1307-z. Epub 2009 Mar 5.
Structural refuges within which prey can escape from predators can be an important limiting resource for the prey. In a manner that resembles the childhood game of musical chairs, many prey species rapidly retreat to shared, unguarded refuges whenever a predator threatens, and only when refuges are relatively abundant do all prey individuals actually escape. The key feature of this process is that the per capita prey mortality rate depends on the ratio of prey individuals to refuges. We introduce a new class of mortality functions with this feature and then demonstrate statistically that they describe field mortality data from a well-studied coral reef fish species, the Caribbean bridled goby Coryphopterus glaucofraenum, substantially better than do several mortality functions of more conventional form.
猎物可用来躲避捕食者的结构性庇护所，可能成为限制猎物数量的重要资源。这一过程类似于儿童游戏“抢座位”，许多猎物物种在捕食者出现威胁时，会迅速退到共享的、无人看守的庇护所，只有当庇护所相对充足时，所有猎物个体才能真正逃脱。这一过程的关键特征是，猎物的人均死亡率取决于猎物个体与庇护所的比例。我们引入了具有这一特征的一类新的死亡率函数，然后通过统计证明，它们比几种更传统形式的死亡率函数能更好地描述来自一种经过充分研究的珊瑚礁鱼类——加勒比缰虾虎鱼（Coryphopterus glaucofraenum）的野外死亡率数据。
