Tests of Alternative Models of Prey Consumption by Predators, Using Ant-Lion Larvae

Publisher Website
Google Scholar
Abstract
When fed 1 ant/day the amount of food extracted per prey by larvae of the ant-lion Macroleon quinquemaculatus was independent of predator size or hunger level. Feeding time was constant within an instar but varied between instars. When fed prey at 1 h intervals extraction efficiency per prey again remained constant but feeding time declined with successive prey. This pattern is consistent with the hypothesis that the rate of prey digestion determines feeding time. Another experiment showed that the rate at which the contents were extracted from the body did not determine feeding time in line with the hypothesis. Differences in the extraction efficiency of larvae feeding on different prey species are due to the presence in some prey of defensive secretions which the larvae do not ingest. Variation in extraction efficiency also results from incomplete consumption of the ant by the ant-lion. There is little difference in the rates of energy intake predicted by the gut-limitation and optimal foraging hypotheses; the factors affecting the level of gut fullness are of greater importance in determining the rate of prey consumption.

This publication has 1 reference indexed in Scilit: