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Bob Gresswell, Ph.D.

 I am a USGS emeritus research biologist and affiliate assistant professor in the Department of Ecology at Montana State University.  My research is focused on the factors that influence fish abundance, distribution, and life history within, and among watersheds, and how these relationships change in through time. 

Research Interests: My interest in the role of disturbance in shaping the aquatic systems has led to research on the interactions among landscape-scale environmental features, instream habitat characteristics, and cutthroat trout abundance and distribution.  Currently my research is focused on the effects of fire, timber harvest, invasive species, and climate change on persistence of native trout in the Intermountain West.  I have been involved with the lake trout issue in Yellowstone Lake since these invaders were first discovered in 1994 and act as chair of the lake trout suppression independent scientific review panel that was formed 2008.

Recent Accomplishments


  • Ph.D. Fisheries Science. 1994. Oregon State University
  • M.S. Wildlife Science. 1973. Utah State University
  • B.S. Biology. 1970. University of New Mexico

Professional Studies/Experience


Professional societies/affiliations/committees/editorial boards

Honors, awards, recognition, elected offices

Scientific/Oral Presentations, Abstracts

Science and Products