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Adam Hansen
Adam Hansen

​​​​​​​​Aquatic Research Scientist, Lake and Reservoir Ecology​​

Aquatic Research Scientist, Adam Hansen.

View Adam's Full CV​.​​​​​​​​​

Contact Information

317 W Prospect Rd, Fort Collins, CO 80526
Phone: 970-472-4432


  • Ph.D., Aquatic  and Fishery Science — University of Washington, 2014

  • B.S., Fishery Biology —​ Colorado State University, 2008

Current or Recent Positions

  • Aquatic Research Scientist – Colorado Parks and Wildlife, 2015-Current

  • Research Scientist Engineer III – Washington Cooperative Fish and Wildlife Research Unit, School of Aquatic and Fishery Sciences, University of Washington, 2013-2015

  • Graduate Fellow and Research Assistant – Washington Cooperative Fish and Wildlife Research Unit, School of Aquatic and Fishery Sciences, University of Washington, 2009-2013

  • Research Associate I – Department of Fish, Wildlife, and Conservation Biology, Colorado State University, 2008-2009

Current or Recent Research Projects

  • Quantifying the direct and indirect effects of illegally introduced or undesirable fish species on managed sport fish in Colorado reservoirs

  • Assessing factors influencing the feeding, growth, and survival of kokanee salmon and developing strategies for the long-term maintenance of Colorado’s kokanee program

  • Evaluating the effects of fishing tournaments and angler harvest on fish populations in small Colorado impoundments

  • Effects of dam operations on reservoir habitat and fish populations

  • Understanding the effects of gill lice infection on trout and salmon at the individual and population levels 

  • Ongoing use of standard gillnetting techniques to track trends in the abundance, size-structure, and health of lake trout populations 

  • Ongoing historical collections of zooplankton and Mysis shrimp in key waters for monitoring long-term environmental change​

Areas of Interest/Expertise

I’m broadly interested in the ecology of large lakes and reservoirs. I research how interactions among climate, human use, reservoir operations, environmental conditions, fish behavior and physiology, and food web structure work to either limit or promote the growth and survival of native and sport fish. I use field sampling, modeling, and the occasional experiment to diagnose the primary factors (i.e., harvest, habitat, food supply, competition, predation, and disease) limiting the production of important populations of fish and to identify/evaluate alternative approaches for improving or maintaining lake and reservoir fisheries.    


Hansen, A.G., J.A. Gardner, K.A. Connelly, M. Polacek, and D.A. Beauchamp. 2018. Trophic compression of lake food webs under hydrologic disturbance. Ecosphere 9(6):e02034.

Spanjer, A.R., P.W. Moran, K.A. Larsen, L.A. Wetzel, A.G. Hansen, and D.A. Beauchamp. 2018. Juvenile coho salmon growth and health in streams across an urbanization gradient. Science of the Total Environment 625:1003-1012. 

Johnson, B.M., W.M. Pate, and A.G. Hansen. 2017. Energy density and dry matter content in fish: new observations and an evaluation of some empirical models. Transactions of the American Fisheries Society 146:1262-1278. 

Borin, J.M., M.L. Moser, A.G. Hansen, C. Donoghue, D.A. Beauchamp, C. Pruitt, S.C. Corbett, J.L. Ruesink, and B. Dumbauld. 2017. Energetic requirements of the North American green sturgeon (Acipenser medirostris) feeding on burrowing shrimp (Neotrypaea californiensis) in estuaries: importance of temperature, reproductive investment, and residence time. Environmental Biology of Fishes 100:1561-1573.

Hansen, A.G., J.R. Gardner, D.A. Beauchamp, R. Paradis, and T.P. Quinn. 2016. Recovery of sockeye salmon in the Elwha River, Washington, after dam removal: dependence of smolt production on the resumption of anadromy by landlocked kokanee. Transactions of the American Fisheries Society 145:1303-1317.

Sorel, M.H., A.G. Hansen, K.A. Connelly, and D.A. Beauchamp. 2016. Trophic feasibility of reintroducing anadromous salmonids in three reservoirs on the North Fork Lewis River, Washington: prey supply and consumption demand of resident fishes. Transactions of the American Fisheries Society 145:1331-1347.​

Sorel, M.H., A.G. Hansen, K.A. Connelly, A.C. Wilson, E.D. Lowery, and D.A. Beauchamp. 2016. Predation by northern pikeminnow and tiger muskellunge on juvenile salmonids in a high-head reservoir: implications for anadromous fish reintroductions. Transactions of the American Fisheries Society 145:521-536.

Hovel, R.A., D.A. Beauchamp, A.G. Hansen, and M.H. Sorel. 2015. Development of a bioenergetics model for the threespine stickleback Gasterosteus aculeatus. Transactions of the American Fisheries Society 144:1311-1321.

Hansen, A.G., and D.A. Beauchamp. 2015. Latitudinal and photic effects on diel foraging and predation risk in freshwater pelagic ecosystems. Journal of Animal Ecology 84:532-544.

Hansen, A.G., and D.A. Beauchamp. 2014. Effects of prey abundance, distribution, visual contrast, and morphology on selection by a pelagic piscivore. Freshwater Biology 59:2328-2341.

Garcia, R.L., A.G. Hansen, M. Chan, and G.E. Sanders. 2014. Gyrodactylid Ectoparasites in a population of rainbow trout (Oncorhynchus mykiss). The Journal for the American Association for Laboratory Animal Science 53:92-97.

Hansen, A.G.,​ D.A. Beauchamp, and E.R. Schoen. 2013. Visual prey detection responses of piscivorous trout and salmon: effects of light, turbidity, and prey size. Transactions of the American Fisheries Society 142:854-867.

Hansen, A.G., D.A. Beauchamp, and C.M. Baldwin. 2013. Environmental constraints on piscivory: insights from linking ultrasonic telemetry to a visual foraging model for cutthroat trout. Transactions of the American Fisheries Society 142:300-316.

Lepak, J.M., K.D. Kinzli, E.R. Fetherman, W.M. Pate, A.G. Hansen, E.I. Gardunio, C.N. Cathcart, W.L. Stacey, Z.E. Underwood, M.M. Brandt, C.M. Myrick, and B.M. Johnson. 2012. Manipulation of growth to reduce mercury concentrations in sport fish on a whole-system scale. Canadian Journal of Fisheries and Aquatic Sciences 69:122-135.​

Electronic copies of all publications can be found at:​