Krzysztof Sakrejda

PhD Candidate

B.A. Chemistry, Vassar College, 2002
M.S. Environmental Studies, University of Oregon, 2005

Advisor: Benjamin Letcher
Dissertation/thesis title: Estimation problems in complex field studies with deep interactions: time-to-event models for environmental responses in vital rates

Research Interests

Biology is in a position to answer both basic questions about why the world looks as it does, and pressing social needs. I am focusing on dynamics of small populations relevant to extinction as well as the spread of infectious disease. The most interesting questions to me are those that involve uncertainties about mechanisms, particularly with important trade-offs. To that end I am pursuing questions and modeling methods which give us the opportunity to identify closely related mechanisms.

I am in the Letcher lab, and I am becoming especially familiar with their long-term salmonid community data set and individual-based methodology.

Some relationships in this complex data set, such as the postulated relationship between movement strategy and growth, are difficult to separate but key to understanding population dynamics. We seek to set multiple statistical analysis in the framework of a Bayesian capture-recapture model to explicitly include the timing and covariance of related effects in our analyses.

The biggest project I am involved in currently seeks to predict the responses of Atlantic salmon to changing climate regimes. We are also interested in the optimal application of limited conservation resources and are addressing both questions through simulations of survival, growth, and movement on a network space.

Finally, I am currently tying up a project looking at patterns and drivers of territoriality in the three Salmonids which occur on our study site: Salmo salar (Atlantic salmon), Salvelinus fontinalis (brook trout), and Salmo trutta (brown trout).