Kruse Kipp C
Department of Zoology, Eastern Illinois University, 61920, Charleston, Il, USA.
Oecologia. 1983 Jun;58(3):383-388. doi: 10.1007/BF00385240.
The feeding behavior of predaceous beetle larvae (Dytiscus fasciventris) on American toad (Bufo americanus) tadpoles was investigated in the laboratory. The rate of food extraction from an individual tadpole decreases as the prey item is being depleted. Beetles hand fed single tadpoles were shown to have a significantly longer mean handling time than beetles capturing similar size tadpoles from constant prey densities of 5 or 20 tadpoles/1. Handling times were not correlated with mean intercatch intervals but were found to decrease throughout a 10-tadpole catch sequence at all prey densities. Beetles allocated less time per unit weight to large prey items than to smaller tadpoles. However, the marginal ingestion rate (amount consumed/unit of handling time) did not differ with prey size throughout a 10-tadpole catch sequence. These results support the rate expectation hypothesis (Charnov 1976) as an explanation for time allocation to patches.
在实验室中研究了捕食性甲虫幼虫（美洲龙虱）对美洲蟾蜍蝌蚪的捕食行为。随着猎物数量的减少，从单个蝌蚪获取食物的速率会降低。结果表明，人工投喂单个蝌蚪的甲虫的平均处理时间显著长于从每1升含5只或20只蝌蚪的恒定猎物密度中捕获相似大小蝌蚪的甲虫。处理时间与平均捕食间隔时间无关，但发现在所有猎物密度下，甲虫在捕获10只蝌蚪的过程中，处理时间会逐渐减少。与较小的蝌蚪相比，甲虫对大型猎物每单位重量分配的时间更少。然而，在捕获10只蝌蚪的过程中，边际摄食率（消耗量/处理时间单位）并不随猎物大小而变化。这些结果支持了速率期望假说（查诺夫，1976年），以此来解释对斑块的时间分配。
