In general, I study the processes that govern the growth and behavior of stream fishes and the success of their populations.

Much of my research concerns drift feeding, a common behavior in which fish hold a steady position facing into the current and dart back and forth to intercept passing items of food. I look at a wide range of other topics that either influence this behavior (such as cognitive ecology and invertebrate drift) or mediate its effect on populations (such as territoriality and bioenergetics). I have focused much of my early career on feeding behavior because it forms one of the primary links between animals and their environment. It determines how energy intake depends on environmental conditions, which in turn affects habitat choices, competition, growth, and survival.

This work on feeding behavior stems from a broader interest in deepening our quantitative understanding of the connections between the behavior and physiology of animals and patterns we detect in their behavior at larger scales, such as the decline of a population or a shift in its habitat usage.


Primary Specialties

  • Behavioral ecology in general
  • Population dynamics
  • Territoriality
  • Drift feeding behavior
  • Habitat selection
  • Stereo video methods for 3-D measurement
  • Aquatic entomology
  • Individual-based modeling
  • Machine learning
  • Invertebrate drift
  • Bioenergetics

Other Interests

  • Cognitive ecology
  • Pattern-oriented modeling
  • Complex adaptive systems

Academic Projects

  • Chena River Drift Study

    A collaboration with ADF&G and the University of Alaska to measure and model invertebrate drift and inedible debris that distracts foraging salmon.

  • Drift Model Project

    My Alaska-based post-doctoral project through the University of Georgia focused on juvenile Chinook Salmon, but with important components also studying Arctic Graying and Dolly Varden.

    We developed new, more accurate models of drift-feeding behavior, and tested those models on three species in interior Alaska (juvenile Chinook salmon, Arctic grayling, and dolly varden).

    See DriftModelProject.org for more information.

  • Chena River Chinook Salmon Study

    At the University of Alaska, I was one of four graduate students on this project studying several aspects of Chena River Chinook Salmon ecology.

    My dissertation consisted of chapters on 3-D video methods (see VidSync software), the effects of fine drifting debris on drift-feeding fish, 3-D territoriality within schools of juvenile Chinook salmon, and the relationship between stream discharge and the population dynamics of Chena River Chinook Salmon. Other students looked at primary productivity, fish growth and diet, and the invertebrate drift in the Chena.

    See my dissertation for details on this work.

  • VidSync Software

    A free, open-source Mac application I wrote to do advanced scientific video analysis.

    VidSync enables fast, user-friendly 2-D and 3-D measurement and event logging using one or more synchronized video clips. I developed it as a part of my Ph.D. project on the Chena River Chinook Salmon study, expanding upon a foundation laid by the work of Nick Hughes an Lon Kelly. It has been used for many fisheries research projects worldwide, including in New Zealand, Argentina, the Seychelles, Mexico, and several studies in the U.S.

    See VidSync.org for more details.

  • BioenergeticHSC

    A free, open-source, cross-platform graphical interface to drift foraging models and habitat suitability curves.

    See my Publications page for papers with Sean Naman, Jordan Rosenfeld, and others describing the capabilities of this software. I wrote the initial code, which was refined and rigorously tested by Sean and Jordan. I have since had multiple small contracts to expand the program’s features.

Other Projects

  • Troutnut.com

    Troutnut.com is melds my zeal for fly fishing with my academic interests. It contains an encyclopedia of aquatic entomology for fly anglers.

    Troutnut.com contains detailed descriptions of the life history and behavior of thousands of aquatic insect species, which I compiled from an extensive systematic review of the fly fishing literature. It includes thousands of high-quality closeup photos of the aquatic insect species fly anglers seek to imitate. It is one of the web’s most authoritative sites on many of the scientific aspects of fly fishing, thanks in large part to a community of contributors (including many professional entomologists) who continually help improve its content.

    I began developing the site 2003 and spent a year improving it between undergraduate and graduate school.