Skip to Main Content
Competition and predation as mechanisms for displacement of greenback cutthroat trout by brook troutAuthor(s): C. C. McGrath; W. M. Lewis
Source: Transactions of the American Fisheries Society. 136: 1381-1392.
Publication Series: Miscellaneous Publication
PDF: View PDF (425 B)
DescriptionCutthroat trout Oncorhynchus clarkii frequently are displaced by nonnative brook trout Salvelinus fontinalis, but the ecological mechanisms of displacement are not understood. Competition for food and predation between greenback cutthroat trout O. c. stomias and brook trout were investigated in montane streams of Colorado. A replicated field study was used to describe the population density, diet, stomach fullness, and body condition of the two species in allopatry and sympatry. Population data confirmed that brook trout displaced greenback cutthroat trout at sites where the species occur together. The diets of the two species were different; cutthroat trout consumed more prey items and a wider variety of prey than brook trout. Sympatry did not influence gut fullness or body condition for either species. Predation occurred at low rates that did not account for declines in populations of greenback cutthroat trout. Instead, population data suggest that the displacement of greenback cutthroat trout by brook trout occurs through a bottleneck on recruitment due to the mortality of eggs or juvenile cutthroat trout.
- You may send email to firstname.lastname@example.org to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationMcGrath, C. C.; Lewis, W. M., Jr. 2007. Competition and predation as mechanisms for displacement of greenback cutthroat trout by brook trout. Transactions of the American Fisheries Society. 136: 1381-1392.
Keywordscutthroat trout, Oncorhynchus clarkii, nonnative brook trout, Salvelinus fontinalis, competition, predation
- Alien invasions in aquatic ecosystems: toward an understanding of brook trout invasions and potential impacts on inland cutthroat trout in western North America
- Role of climate and invasive species in structuring trout distributions in the interior Columbia River Basin, USA
- Analyzing tradeoffs between the threat of invasion by brook trout and effects of intentional isolation for native westslope cutthroat trout
XML: View XML