Effects of climate-related stream factors on patterns of individual summer growth of Cutthroat Trout

Transactions of the American Fisheries Society
By: , and 



Coldwater fishes are sensitive to abiotic and biotic stream factors, which can be influenced by climate. Distributions of inland salmonids in North America have declined significantly, with many of the current strongholds located in small headwater systems that may serve as important refugia as climate change progresses. We investigated the effects of discharge, stream temperature, trout biomass, and food availability on summer growth of Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri, a species of concern with significant ecological value. Individual size, stream discharge, sample section biomass, and temperature were all associated with growth, but had differing effects on energy allocation. Stream discharge had a positive relationship with growth rates in length and mass; greater rates of prey delivery at higher discharges probably enabled trout to accumulate reserve tissues in addition to structural growth. Temperature effects were positive but not significant, and support in growth models was limited, likely due to the cold thermal regimes of the study area. The strength of the discharge effect on growth suggests that climate adaptation strategies for coldwater fishes that focus solely on thermal characteristics may be misleading and highlights the importance of considering multiple factors, including hydrologic regimes, in conservation planning.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Effects of climate-related stream factors on patterns of individual summer growth of Cutthroat Trout
Series title Transactions of the American Fisheries Society
DOI 10.1002/tafs.10106
Volume 148
Issue 1
Year Published 2019
Language English
Publisher American Fisheries Society
Contributing office(s) Northern Rocky Mountain Science Center
Description 14 p.
First page 21
Last page 34
Country United States
State Montana, Wyoming
Other Geospatial Shields River, Spread Creek
Google Analytic Metrics Metrics page
Additional publication details