Predator diversity stabilizes and strengthens trophic control of a keystone grazer.

Published

Journal Article

Despite the global vulnerability of predators to extinction, and the critical functional role they play in many ecosystems, there have been few realistic tests of the consequences of predator species deletion (conversely, predator diversity) in natural ecosystems. We performed a four-month field experiment in a southeastern United States salt marsh to test the role of predatory crab diversity in regulating populations of a keystone grazer that can decimate marsh vegetation at high densities. Our results revealed that a combination of this system's two resident predator species, in comparison to individual species, both stabilize and strengthen predation rates on the potent grazer. Monthly monitoring of predation rates from intense, hot summer months into the cooler autumn indicate this diversity benefit arises from predators responding differentially to changing environmental conditions across seasons. This study provides some of the first experimental field support for the insurance hypothesis from marine ecosystems, suggests that predator temporal complementarity may be more common than currently perceived, and argues for conservation of predator diversity to ensure reliable and effective control of potentially habitat-destroying grazers.

Full Text

Duke Authors

Cited Authors

  • Griffin, JN; Silliman, BR

Published Date

  • February 2011

Published In

Volume / Issue

  • 7 / 1

Start / End Page

  • 79 - 82

PubMed ID

  • 20739314

Pubmed Central ID

  • 20739314

Electronic International Standard Serial Number (EISSN)

  • 1744-957X

International Standard Serial Number (ISSN)

  • 1744-9561

Digital Object Identifier (DOI)

  • 10.1098/rsbl.2010.0626

Language

  • eng