Article
Heterogeneity in body size and habitat complexity influence community structure
Journal of Freshwater Ecology
(2018)
Abstract
Food web studies commonly ignore individual variation within a population and variation in the environment and assume these factors have insignificant effects on community dynamics relative to interspecific interactions. However, variation in body sizes within a population (size structure) and the physical structure of habitats (habitat complexity) can both affect interspecific interactions independently, with possible interactive effects. Using experimental mesocosms, we examined effects of predator size structure and habitat complexity on predation by two common predators in fishless ponds: larval aquatic beetles (Cybister fimbriolatus) and larval dragonflies (Anax junius). Cannibalism, intraguild predation, and predation on shared prey were measured at two levels of habitat complexity crossed with six size-structured pairs of predators. We found that highly complex habitats sustain a higher prey density because prey can take refuge from predators. Additionally, size structure had direct (size better predicted predation rate than did species identity) and indirect (IGP and cannibalism lowered predation rates) effects on consumptive interactions, which changed the composition and density of the predator guild. The identified size- and habitat-mediated mechanisms can change the frequencies of intraguild vs. interguild predation (a balance important in determining top–down control of predators), and therefore we argue that these sources of heterogeneity should be included in community ecology studies where possible.
Keywords
- Size structure,
- intraguild predation,
- cannibalism,
- community structure,
- Anax junius,
- Cybister fimbriolatus
Disciplines
Publication Date
April 10, 2018
DOI
10.1080/02705060.2018.1435429
Publisher Statement
This is an Open Access article.
Citation Information
Shannon K. Carter, Darrell Vodopich and Patrick W. Crumrine. "Heterogeneity in body size and habitat complexity influence community structure" Journal of Freshwater Ecology Vol. 33 Iss. 1 (2018) p. 239 - 249 ISSN: 2156-6941 Available at: http://works.bepress.com/patrick-crumrine/6/
Creative Commons license
This work is licensed under a Creative Commons CC_BY International License.