Finding and sharing depletable patches: when group foraging decreases intake rates
Finding and sharing depletable patches: when group foraging decreases intake rates
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寻找并共享可消耗的斑块：当群体觅食降低摄入率时
DOI：
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发表时间：
1988
期刊：
影响因子：
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通讯作者：
J. Ekman
中科院分区：
文献类型：
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作者：
M. Hake;J. Ekman
绿雀在群体中更快地找到食物，因为它们通过喂养群友来了解食物的位置（局部增强）。尽管如此，由于局部增强搜索效率的收益是不够的，以平衡较小的份额从耗尽补丁的个人在一个羊群和摄入率的平均个人下降。因此，不可能建立在增加每个成员摄入量的基础上的稳定的觅食群体。搜索效率的提高下降，增加羊群规模的补丁重访的比例增加。尽管更快地找到食物，但群体牧草的摄入率会降低，除非斑块太大或太短暂而无法耗尽。在组觅食的摄入率下降进一步要求，孤独的鸟类获得使用记忆，而觅食，这是一个好处，这是在羊群侵蚀。尽管如此，饥饿风险的降低可以调和群体觅食与摄入率的降低，因为局部增强减少了食物摄入量的差异。
Greenfinches located food faster in groups as they were informed by feeding flock mates about its location (local enhancement). Still, gains in search efficiency due to local enhancement were insufficient to balance the smaller shares obtained from depletable patches by individuals in a flock and the intake rate for the average individual decreased. Stable foraging groups, based on an increased intake rate for every member, are therefore not possible. Improvements in search efficiency decreased with increasing flock size as the proportion of patch revisits increased. In spite of finding food faster, intake rates of group forages will decrease unless patches are too large or too ephemeral to be depleted. The decrease in intake rates at group foraging further requires that solitary birds gain from using memory while foraging, a benefit which is eroded in flocks. Still, a reduced risk of starvation could reconcile group foraging with reduced intake rates since local enhancement reduces the variance in food intake.