Cooperative Fish and Wildlife Research Units Program: New Mexico
Education, Research and Technical Assistance for Managing Our Natural Resources

New Mexico Project

Impacts of Drought on Southwestern Cutthroat Trout: Influences of Changes in Discharge and Stream Temperature on the Persistence of Rio Grande Cutthroat Trout Populations

July 2015 - December 2019


Participating Agencies

  • National Climate Change and Wildlife Science Center and Climate Science Centers
Rio Grande cutthroat trout

Rio Grande cutthroat trout (RGCT; Oncorhynchus clarkia virginalis) are the southernmost subspecies of cutthroat trout and currently occupy less than 12% of their historic range. Loss of habitat due to competition and hybridization with introduced trout and habitat alteration has restricted the remaining 122 populations to small (5.8 km median length) isolated habitat patches. A stream temperature and discharge monitoring program also identified that the majority of occupied habitat patches, while currently thermally suitable for the subspecies, have very low summer baseflows (< 1.0 cfs) which restrict fish movement and increases the risk of population extirpation due to stochastic disturbances (i.e., drought). We are using otoliths and multistate capture-mark-recapture data collected along a temperature and stream drying gradient to assess life-history traits and persistence of RGCT. In addition, we are using secondary production to determine if stream temperature has affected RGCT abundance and growth. We are working with USGS National Wildlife and Climate Adaptation Science Center, US Forest Service (Santa Fe, Carson), and the New Mexico Department of Game and Fish. Our work will assist with the conservation of the most southern subspecies of cutthroat trout through in a more comprehensive long term management strategy.

Presentations Presentation Date
Huntsman, B.M., Caldwell, C.A., Lynch, A.J., and Abadi, F. 2018. Rio Grande Cutthroat Trout population dynamics and persistence along a temperature and precipitation gradient. American Fisheries Society Annual Meeting, Atlantic City, New Jersey, August 20-24, 2018. 2018-08-20
Flynn, L.M., B.M. Huntsman, C.A. Caldwell, and A.J. Lynch. 2018. Effects of biotic and abiotic factors on the specific growth rates of Rio Grande cutthroat trout, Oncorhynchus clarkii virginalis. Western Division of the American Fisheries Society Annual Meeting. Anchorage, Alaska. 2018-05-23