HR: 1330h
AN: NB33Q-01    [Abstracts]
TI: Impacts of Size Structure on Intraguild Predation in Pond Communities
AU: * Crumrine, P W
EM: crumrinepw@longwood.edu
AF: Department of Natural Sciences, Longwood University, 201 High Street, Farmville, VA 23909 United States
AU: * Crumrine, P W
EM: crumrinepw@longwood.edu
AF: Blandy Experimental Farm, 400 Blandy Farm Lane, Boyce, VA 22620 United States
AB: Size structure, the degree to which individuals in a population vary in size, can greatly influence the dynamics of intraguild predation (IGP) within ecological communities. I manipulated the degree of size structure within assemblages of IG predators and IG prey to examine impacts on the direction and intensity of IGP in communities of larval dragonflies and larval water beetles. In pond enclosure studies, Pachydiplax longipennis (IG prey) mortality was lower when exposed to size structured assemblages of Anax junius (IG predator) than when exposed to only large A. junius at the same density. Effects of size-structured assemblages of A. junius on shared prey, Ischnura verticalis, were similar to the effects each size class alone at the same density. Separate experiments with Dytiscid water beetle larvae as IG predators and size-structured assemblages of A. junius as IG prey suggest that IG prey size structure plays only a limited role in mediating shared prey survival. These experiments highlight the importance of size structure as a characteristic that may promote the coexistence of predators in IGP systems.
DE: 9810 New fields (not classifiable under other headings)
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly