2009年8月17日 星期一

換個口味吃吃否則就是找死 - 在不同的天敵捕食壓力下以色列產貝爾雪瓦棘趾蜥的食性轉換

文獻來源: Hawlena D, Pérez-Mellado V. 2009. Change your diet or die: predator-induced shifts in insectivorous lizard feeding ecology. Oecologia 161(2): 411-419.

Abstract
Animal feeding ecology and diet are influenced by the fear of predation. While the mechanistic bases for such changes are well understood, technical difficulties often prevent testing how these mechanisms interact to affect a mesopredator’s diet in natural environments. Here, we compared the insectivorous lizard Acanthodactylus beershebensis’ feeding ecology and diet between high- and low-risk environments, using focal observations, intensive trapping effort and fecal pellet analysis. To create spatial variation in predation risk, we planted “artificial trees” in a scrubland habitat that lacks natural perches, allowing avian predators to hunt for lizards in patches that were previously unavailable to them. Lizards in elevated-risk environments became less mobile but did not change their microhabitat use or temporal activity. These lizards changed their diet, consuming smaller prey and less plant material. We suggest that diet shifts were mainly because lizards from risky environments consumed prey items that required shorter handling time.
圖片連結: לוכד נחשים