Trophic overlap between native and invasive stream crayfish

Hydrobiologia
By:  and 

Links

Abstract

We examined trophic dynamics of a stream food web where invasive Orconectes neglectus appear to be displacing native O. eupunctus in the Spring River drainage of the Ozark Highlands, Missouri and Arkansas, USA. We collected crayfish species and possible food sources seasonally from a site of sympatry on the South Fork Spring River. We determined diet overlap and potential for competition between O. eupunctus and O. neglectus, and investigated seasonal variation using carbon and nitrogen stable isotope analyses and gut content analyses. Gut content analysis showed both species of crayfish consumed mainly detritus during summer and spring, with other prey categories varying by species and season. Stable isotope analysis showed that O. eupunctus and O. neglectus relied on invertebrates as a major energy and nutrient source throughout summer, autumn, and spring, and the two species showed differences in their stable isotope signatures during spring and summer, but not autumn. Given the trophic overlap between O. eupunctus and O. neglectus, there is a potential for the two species to compete for food and to be ecologically redundant. Ecological redundancy can lead to reduced effects on ecosystem function post-invasion, and therefore examining ecological redundancy of potential invaders should be a conservation priority.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Trophic overlap between native and invasive stream crayfish
Series title Hydrobiologia
DOI 10.1007/s10750-015-2457-0
Volume 766
Issue 1
Year Published 2016
Language English
Publisher Springer
Contributing office(s) Coop Res Unit Atlanta
Description 10 p.
First page 237
Last page 246
Country United States
State Arkansas, Missouri
Other Geospatial Ozark Highlands, Spring River
Google Analytic Metrics Metrics page
Additional publication details