Climate Change and Native Salmonids Collaborative Research Site

Welcome to the Climate Change and Native Salmonids collaborative research site, developed by a cooperative research project team consisting of fisheries researchers from USGS, US Forest Service, and Trout Unlimited. Our goal is to host a dynamic array of resources for stakeholders interested in the consequences of various climate scenarios to native trout management and restoration.


State and federal agencies and non-governmental organizations are increasingly consumed with the recovery and restoration of native trout and salmon, all of the family Salmonidae, throughout the western United States. Almost all of the native inland cutthroat species, grayling and bull trout have been proposed for listing under the Endangered Species Act and a number are currently listed as “Threatened”.

Trout, grayling, and char historically inhabited a variety of freshwater habitats (streams, rivers, lakes, ponds, reservoirs), but have declined due to habitat degradation, fragmentation, and introductions of nonnative species. The remaining intact populations of native trout, char, and grayling species are largely restricted to small, fragmented headwater habitats. Recent localized extinction of these small populations caused by wildfires and subsequent floods have highlighted their vulnerability.

Complicating these issues is global warming and associated climate change, which are likely to increase air and water temperatures, increase the risk of catastrophic fire, change the timing and quantity of water from snowpack, increase winter flooding in some areas, and provide habitat conditions that favor introduced species. Understanding how effects of climate change will influence habitat for native fish is critical for effective management and recovery of these species.


Our team is studying how global warming and associated climate change may drive landscape scale impacts that affect the fresh water habitats of key native fish species. Specific research questions we will explore include:

  • What is the geographic distribution of target species or populations in relationship to current temperature and flow regimes?
  • How are the flow and temperature regimes likely to change in response to a warming climate, and which habitats and populations will be affected most?
  • How will these large-scale changes in climate affect native salmonid distributions across the western United States?
  • How well do broad scale estimates of the relationship between climate variables (i.e. stream temperature, flow) and native salmonid distribution reflect actual measurements within a basin?

Composite climate risk map of historic and current range for Westslope cutthroat trout. Adapted from Williams et al. 2007.Outputs of the project are:

  1. Develop a database including all existing species distribution and habitat information, and air and water temperature data.
  2. Develop maps defining existing and projected future distributions of native salmonids factoring in anticipated temperature, hydrology, and non-native impacts alone and in combination.
  3. Develop an open file report of this analysis that would include data analysis, maps and forecasts for each of the species listed.
  4. Preparation of a scientific journal article that synthesizes the work.
  5. Distribution of information through a series of workshops and meetings with resource managers to update them on the projected change scenarios.

By developing these types of forecasting tools, we can assist wildlife managers in predicting potential climate change induced impacts on various fish species throughout the Rocky Mountains and the interior western United States.

l Progress To Date l