The structure of natural communities is shaped by both abiotic characteristics and by the ongoing processes of community assembly. Important components of this process are the habitat selection behaviors and subsequent survival of colonists, both in the context of temporal changes in the abiotic characteristics and priority effects driven by earlier colonists. Aquatic beetles are prevalent in temporary freshwater systems, form speciose assemblages, and can arrive in ponds soon after they fill. While beetles have the potential to influence community structure through post-colonization interactions (predation and competition), our goal was to determine whether the presence of existing beetle assemblages (versus patches without beetles) influence the colonization and oviposition of a diverse group of animals in a naturally-colonized experimental landscape. We established mesocosms containing naturally-occurring beetle assemblages and observed colonization and oviposition patterns of aquatic beetles, hemipterans, gray treefrogs, and mosquitoes.
Results/Conclusions
Treefrogs (Hyla chrysoscelis) and mosquitoes (Culex restuans) both deposited fewer eggs in patches containing beetle assemblages, while two beetle taxa and one hemipteran colonized those patches at lower rates. One beetle species colonized patches containing beetle assemblages at higher rates, while six beetle taxa exhibited no colonization differences between treatments. Our results illustrate the importance of habitat selection in determining the species composition of habitat patches while emphasizing the role of priority effects in influencing patterns of community assembly. Habitat selection in response to abiotic and biotic characteristics of habitat patches can potentially create greater spatiotemporal niche separation among the numerous, often closely-related species (phylogenetically and trophically) that can be simultaneously found in similar patches across landscapes.