Dr. Clint Muhlfeld

Research Ecologist
West Glacier


U.S. Geological Survey
Northern Rocky Mountain Science Center
Glacier Field Station, Glacier National Park
West Glacier, Montana 59936

Phone 406-888-7926
Fax 406-888-7923

Ph.D. 2008. Fish and Wildlife Biology, Montana State University, Bozeman.
Ph.D. Dissertation: Behavioral, ecological, and fitness consequences of hybridization between native westslope cutthroat trout and nonnative rainbow trout

M.S. 1999. Fishery Resources, University of Idaho.
M.S. Thesis: Seasonal habitat use and movement of redband trout in the Kootenai River drainage, Montana

B.S. 1994. Aquatic Biology, University of Montana (1990-1993, University of Maine)

Research interests:

I am a Research Aquatic Ecologist for the USGS Northern Rocky Mountain Science Center stationed in Glacier National Park and Assistant Research Professor at the University of Montana, Flathead Lake Biological Station. My general research interests encompass the fields of aquatic ecology, fisheries biology, and conservation biology.

My research goal is to understand how aquatic species interact with physical and biological templates over space and time to inform conservation and management. Specifically, my applied research focuses on assessing how human stressors – invasive species, habitat modification, and climate change – influence native salmonids and rare alpine macroinvertebrates in the Rocky Mountains of the United States and Canada.

My published research spans a range of scientific questions and conservation issues from examining the evolutionary and ecological impacts of invasive species on native fishes, assessing life history and genetic diversity of native salmonids, assessing the status of threatened freshwater species, investigating the impacts of dams and barriers on aquatic species and ecosystems, developing quantitative models (e.g., stream temperature, instream flow/habitat, bioenergetics, riverscape connectivity, population viability) to predict species’ responses to environmental change, to understanding and predicting the impacts of climate warming on freshwater species and ecosystems.

I particularly enjoy collaboration and multidisciplinary research, and advising and educating graduate students working on various aspects of freshwater ecology and conservation biology. Currently, I actively participate on several regional, national, and international science teams that address natural resource issues facing aquatic ecosystems. My hope is that the ecological integrity of our watersheds will be preserved for future generations through research-informed management and education.


  • Aquatic ecology
  • Fisheries biology
  • Invasive species
  • Climate change
  • Conservation biology

Professional experience:

  • 2007-present. Research Aquatic Ecologist, USGS-Northern Rocky Mountain Science Center, Glacier Field Station, Glacier National Park
  • 2011-present. Assistant Research Professor, Flathead Lake Biological Station, The University of Montana
  • 2009-present. Affiliate Faculty Member, Wildlife Biology Program, The University of Montana, Missoula
  • 2009-present. Affiliate Faculty Member, Environmental Studies Program, The University of Montana, Missoula
  • 2009-present. Affiliate Faculty Member, Department of Ecology, Montana State University, Bozeman
  • Spring 2007. Instructor, Montana State University: Principles of Fish and Wildlife Management (FWL 301)
  • 1999-2007. Fisheries Research Biologist, Montana, Fish, Wildlife & Parks, Kalispell
  • 1994-2006. Fisheries Research Technician, Montana, Fish, Wildlife & Parks, Libby