GOTELLI DEB-9615708 Antlion larvae build and maintain steep-sided pits which are used to trap small arthropods. The probability of the antlion reaching adulthood depends on its ability to locate a suitable site for its pit and to determine when to change sites while avoiding predation. This proposal attempts to unravel the behavioral rules that antlions use in deciding whether or not to stay in a particular pit. The investigators will combine computer models (individual-based simulation models and dynamic programming models) with field data and field and laboratory experiments to evaluate a wide variety of potential behavioral strategies and assess their success under a range of ecological conditions. This work will significantly expand the current understanding of the ecological impact of predators, such as antlions, that sieve prey from the environment. Ant lions are significant predators on local ant communities, and they exert a potentially significant effect on the populations of these economically important organisms. The investigators field experiments will provide data that will enable a quantifying of the potential seasonal impact of antlion predation on local ant populations. This research will provide information on a general class of sit-and-wait predators which are important insect predators.