Dr. Charles Gowan


  • Post Doc. Colorado State University, 1996
  • Ph.D. Colorado State University, Fisheries Biology, 1995
  • M.S. Michigan State University, Fisheries Biology, 1985
  • B.S. State University of New York, College of Environmental Science and Forestry, Forest Biology, 1982
  • A.S. Herkimer County Community College (NY), Environmental Science, 1980


BIOL 121 Integrative Biology I
BIOL 350 Biostatistics
BIOL 230 Ichthyology
BIOL 310 Freshwater Ecology
EVST 105, 305, 405, Environmental Problem Solving I, II, and III

Research Interests

(why I like being a biologist, and why you would too!)

My primary research interest is the ecology of trout in streams. I started my career in Michigan trying to understand how stream flows, altered by irrigation withdrawals, affect trout habitat and abundance. This led to work in the Pacific Northwest studying how hydroelectric dams affect salmon, including how the dams could be engineered differently in order to reduce their harmful effects. A move to Colorado allowed me to study certain techniques for improving trout habitat in ways that favorably influence survival rates, reproductive success, immigration, and emigration.

Most recently, my work in Virginia has focused on how individual trout learn to recognize each other, and how this learning affects how they interact when they compete for food and space. It turns out that trout are really smart. Perhaps not surprisingly, when one fish beats up another (they fight for food), the loser remembers who the winner is and won’t go hear him again. In fact, both the winner and the loser have a series of ritualized behaviors that they use to avoid repeated fights. The winner turns a light color, perks up its fins and swims slowly toward the loser. The loser turns dark, folds its fins, and swims backwards. The interesting thing is that you can have, say, five fish all in the same pool and each one knows exactly who it can beat and who it can’t. This is called a dominance hierarchy wherein there is an “alpha” fish who can beat up everybody, a “beta” who is second in command, and so on down the line. Each fish knows exactly where it stands in the dominance hierarchy.

As if all that isn’t interesting enough, a new fish entering the pool can learn where it is in the dominance hierarchy just by watching other fish fight. This process, technically known as “transitive inference”, helps a fish avoid getting into fights that it is going to lose. For example, say the new fish watches a fight between Fish A and Fish B, and Fish A wins. The new fish then has a fight with Fish B and loses. The new fish now knows that it would lose a fight to Fish A, and Fish A knows this too. So, even though they have never fought before, when Fish A gets near the new fish, Fish A turns a light color and perks up its fins. The new fish turns dark, folds its fins, and swims slowly backward. Both Fish A and the new fish have learned, just by watching each other interact with other fish, who’s the boss. To me, that is simply fascinating. Right now I’m trying to find out how big the hierarchy can be and still have all the fish recognize each other. I know that they can do it with five fish in a pool. 10? 20?

I like to do a mixture of other things besides the trout stuff, particularly work related to protecting the environment. I co-authored a book on statistical methods for monitoring endangered species, and published research on topics including the role of economic analysis in environmental decision-making, the effects of storms on beach erosion, and methods citizens can use to monitor health of their local streams. I authored the engineering guidelines the Commonwealth of Virginia uses when permitting water withdrawals. These guidelines specify how projects need to be built in order to protect fish. I also work with endangered beetles that live on the beaches in Chesapeake Bay, and another population that lives in a small sand dune in southwest Utah and nowhere else on Earth.

Here’s the point: biologists are never bored because animals are never boring.

Selected Publications

Gowan, C., M. K. Young, K. D. Fausch, and S. C. Riley. 1994. Restricted movement in resident stream salmonids: a paradigm lost? Canadian Journal of Fisheries and Aquatic Sciences 51: 2626-2637.

Gowan, C. and K. D. Fausch. 1996. Long-term demographic responses of trout populations to habitat manipulation in six Colorado streams. Ecological Applications 6: 931-946.

Thompson, W. L., G. C. White, and C. Gowan. 1998. Monitoring vertebrate populations. Academic Press, San Diego, CA.

Gowan, C., and K. D. Fausch. 2002. Why Do Foraging Stream Salmonids Move During Summer? Environmental Biology of Fishes 64:139-153.

Albanese, B., P. Angermeier, and C. Gowan. 2003. Designing mark-recapture studies to reduce effects of distance weighting on movement distance distributions of stream fishes. Transactions of the American Fisheries Society 132: 925-939.

Gowan, C., K. Stephenson, and L. Shabman. 2006. Ecosystemvaluation in dam removal decisions: the case of the Elwha. Ecological Economics 56: 508-523.

Gowan, C. 2007. Short-term cues used by foraging trout in a California stream. Environmental Biology of Fishes 78:317–331.

Gowan, C., M. Ruby, R. Knisley, and L. Grimmer. 2007. Stream monitoring methods suitable for citizen volunteers working in the coastal plain and lower piedmont regions of Virginia. American Entomologist Spring 2007: 48-57.

White, S., C. Gowan, K.D. Fausch, J. Harris, and C.W. Saunders. 2011. Response of trout populations in five Colorado streams two decades after habitat manipulation. Canadian Journal of Fisheries and Aquatic Sciences 68: 2057-2063.

White, S., and C. Gowan. 2012. Brook trout use individual recognition and transitive inference to determine social rank. Behavioral Ecology. doi:10.1093/beheco/ars136.

White, S.L. and C. Gowan. 2014. Social learning enhances search image acquisition in foraging brook trout. Environmental Biology of Fishes 97: 523-528.