Meeting Abstract

P3.135  Tuesday, Jan. 6  Effects of Habitat Structure on Predation of Agalychnis callidryas tadpoles by Giant Water Bugs (Belostomatidae) GONYER, Kristy M.*; MCCOY, Michael W.; VONESH, James R.; WARKENTIN, Karen M.; Reed College; Boston University; Virginia Commonwealth University; Boston University gonyerk@reed.edu

Predation success is often affected by abiotic factors such as a habitats structural complexity. Habitat structure can inhibit predator efficiency by hindering search efforts, impeding pursuit of prey, or providing refugia for prey. Conversely, habitat structure can increase predation success when prey are associated with particular structural features or when elements of the habitats structure enhance a predators searching behavior. In this study, I characterize giant water bug (Belostomatidae) foraging behavior and success in different structural environments. Observations revealed that the insects alternate between active searching and use of habitat structure in a sit-and-wait strategy when foraging for red-eyed tree frog (Agalychnis callidryas) tadpoles. To test whether structure affects the behavior and foraging success of belostomatids I constructed mesocosms with artificial structure placed in bottom, mid, or upper water-column, all water-column levels, and without structure. The belostomatids behavior was observed to quantify use of structure and predation success was measured by running 24 hour predation trials. I found that belostomatids tended to use structure when available and they tended to use structure in the lower water column when given a choice. The belostomatids had higher predation success when in tanks with rather than without structure, and predation success was highest when there was structure lower in the water column. In addition, when given a choice, belostomatids tended to use structure in the lower water column where they tended to have the highest foraging success.