Thermal onset of cellular and endocrine stress responses correspond to ecological limits in brook trout, an iconic cold-water fish

Conservation Physiology
By: , and 

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Abstract

Climate change is predicted to change the distribution and abundance of species, yet underlying physiological mechanisms are complex and methods for detecting populations at risk from rising temperature are poorly developed. There is increasing interest in using physiological mediators of the stress response as indicators of individual and population-level response to environmental stressors. Here, we use laboratory experiments to show that the temperature thresholds in brook trout (Salvelinus fontinalis) for increased gill heat shock protein-70 (20.7°C) and plasma glucose (21.2°C) are similar to their proposed thermal ecological limit of 21.0°C. Field assays demonstrated increased plasma glucose, cortisol and heat shock protein-70 concentrations at field sites where mean daily temperature exceeded 21.0°C. Furthermore, population densities of brook trout were lowest at field sites where temperatures were warm enough to induce a stress response, and a co-occurring species with a higher thermal tolerance showed no evidence of physiological stress at a warm site. The congruence of stress responses and proposed thermal limits supports the use of these thresholds in models of changes in trout distribution under climate change scenarios and suggests that the induction of the stress response by elevated temperature may play a key role in driving the distribution of species.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Thermal onset of cellular and endocrine stress responses correspond to ecological limits in brook trout, an iconic cold-water fish
Series title Conservation Physiology
DOI 10.1093/conphys/cov017
Volume 3
Issue 1
Year Published 2015
Language English
Publisher Society for Experimental Biology
Publisher location Oxford
Contributing office(s) Leetown Science Center
Description 12 p.
First page 1
Last page 12
Online Only (Y/N) N
Additional Online Files (Y/N) N