Sensitivity of salmonid freshwater life history in Western US streams to future climate conditions.
Glob Chang Biol. 2013 May 2;
Authors: Beer WN, Anderson JJ
We projected effects of mid-21(st) century climate on the early-life growth of Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) in western United States streams. Air temperature and snowpack trends projected from climate models and observed 20(th) century trends were used to predict future seasonal stream temperatures. Fish growth from winter to summer was projected with temperature-dependent models of egg development and juvenile growth. Based on temperature data from 115 sites, by mid-21(st) century the effects of climate change are projected to be mixed. Fish in warm-region streams that are currently cooled by snowmelt will grow less, and fish in sub-optimally cool streams will grow more. Relative to 20(th) century conditions, by mid-21(st) century juvenile salmonids’ weights are expected to be lower in the Columbia Basin and California Central Valley but unchanged or greater in coastal and mountain streams. Because fish weight affects fish survival, the predicted changes in weight could impact population fitness depending on other factors such as density effects, food quality and quantity changes, habitat alterations, etc. The level of year-to-year variability in stream temperatures is high and our analysis suggests that identifying effects of climate change over the natural variability will be difficult except in a few streams. This article is protected by copyright. All rights reserved.
PMID: 23640715 [PubMed – as supplied by publisher]
via pubmed: school of aquatic an… http://www.ncbi.nlm.nih.gov/pubmed/23640715?dopt=Abstract