Rinaldi Sergio, Gragnani Alessandra, De Monte Silvia
CIRITA, c/o Department of Electronics and Information, Politecnico di Milano, Via Ponzio 34/5, 20133 Milano, Italy.
Theor Popul Biol. 2004 Dec;66(4):277-86. doi: 10.1016/j.tpb.2004.07.002.
When consumers feeding on a resource spend time in avoiding high risks of predation, the predator functional response declines with predator density. While this is well established, less attention has been paid to the dependence of the consumer functional response on predator density. Here we show how the separation of behavioral and ecological timescales allows one to determine both responses starting from an explicit behavioral model. Within the general set-up considered in this paper, the two functional responses can tend toward Holling type II responses when consumers react only weakly to predation. Thus, the main characteristics of the standard Rosenzweig-MacArthur tritrophic food chain (logistic resource and Holling type II consumer and predator) remain valid also when consumers have weak antipredator behavior. Moreover, through numerical analysis, we show that in a particular but interesting case pronounced antipredator behaviors stabilize the system.
当以某一资源为食的消费者花费时间来规避被捕食的高风险时，捕食者功能反应会随捕食者密度的增加而下降。虽然这一点已得到充分证实，但消费者功能反应对捕食者密度的依赖性却较少受到关注。在此，我们展示了行为时间尺度和生态时间尺度的分离如何使人们能够从一个明确的行为模型出发来确定这两种反应。在本文所考虑的一般框架内，当消费者对捕食反应较弱时，这两种功能反应可能趋向于霍林II型反应。因此，当消费者具有较弱的反捕食行为时，标准的罗森茨维格 - 麦克阿瑟三营养级食物链（逻辑斯谛资源、霍林II型消费者和捕食者）的主要特征仍然有效。此外，通过数值分析，我们表明在一个特殊但有趣的情况下，明显的反捕食行为会使系统稳定。
