THE VALUE OF FAT RESERVES AND THE TRADEOFF BETWEEN STARVATION AND PREDATION
THE VALUE OF FAT RESERVES AND THE TRADEOFF BETWEEN STARVATION AND PREDATION
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DOI：
10.1007/bf00047272
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发表时间：
1990-03-01
影响因子：
1.3
通讯作者：
HOUSTON, AI
中科院分区：
文献类型：
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作者：
MCNAMARA, JM;HOUSTON, AI
结果表明，在一系列的模型中，觅食者死于饥饿的概率是一个很好的近似，能量储备的指数函数。使用的时间和能量预算为19克雀形目，我们探讨的后果，在饥饿和捕食，不同水平的能量储备。结果表明，存在一个最优水平L* 的储备，在该水平下，总死亡率（饥饿加捕食）最小化。当环境由于温度或平均总增益的降低或平均搜索时间的增加而恶化时，L* 增加。综合恶化的影响大于其单独影响的总和。在L* 处，捕食的概率远高于饥饿的概率。一个简单的分析模型表明，这一结果将是相当普遍的，但也指出了结果可能不成立的条件。
It is shown that in a range of models, the probability that a forager dies from starvation is, to a good approximation, an exponential function of energy reserves. Using a time and energy budget for a 19g passerine, we explore the consequences, in terms of starvation and predation, of various levels of energy reserves. It is shown that there exists an optimal level L* of reserves at which total mortality (starvation plus predation) is minimized. L* increases when the environment deteriorates as a result of a decrease in either temperature or mean gross gain or an increase in the mean search time. The effect of combined deteriorations is greater than the sum of their individual effects. At L*, the probability of predation is much higher than the probability of starvation. A simple analytic model suggests that this result will be fairly general, but also indicates conditions under which the result might not hold.