SS3.07 Headwater Ecosystems in Forested Landscapes and Beyond
Date: Wednesday, June 12, 2002
Time: 11:45:00 AM
Location: View Royal
 
CooneySJ, Colorado State University, Fort Collins, CO, USA, Scott_Cooney@mail.com
Covich, A, P, Colorado State University, Fort Collins, CO, USA, AlanC@cnr.colostate.edu
Harig, A, L, Trout Unlimited, Boulder, CO, USA, aharig@tu.org
Fausch, K, D, Colorado State University, Fort Collins, CO, USA, kurtf@cnr.colostate.edu
Hobbs, N, T, Colorado State University, Fort Collins, CO, USA, nthobbs@nrel.colostate.edu
 
MODELING CLIMATE CHANGE: EFFECTS OF STREAM WARMING ON RESTORATION OF GREENBACK CUTTHROAT TROUT IN COLORADO
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Directional change in temperature over the next several decades is likely to alter montane distributions of fish. We examine how proposed changes in water temperature may affect restoration of populations of the federally listed greenback cutthroat trout, Oncorhynchus clarkii stomias, in the Colorado Rocky Mountains. Greenback populations persist today only above steep waterfalls that restrict access by non-native trout. Using existing air and water temperature data from 10 high-elevation streams, we modeled future weekly mean water temperature based on projected air-temperature warming scenarios of 2 and 4 C. In these warming scenarios spawning is predicted to begin 2 to 3.3 weeks earlier, respectively. Earlier peak discharge from more rapid snow-melt or rain-on-snow events may also alter these relationships. We conclude that additional new sites to restore greenback populations would likely provide stable populations at warmer, high-elevation streams, but only if non-native fish species are excluded.