Physiological Effects of Climate Change on Hummingbirds
My lab has begun a four-year project to explore how hummingbirds respond physiologically to climate change. This project, which is funded by NASA, is a component of a larger project entitled “Combining Remote-Sensing and Biological Data to Predict the Consequences of Climate Change on Hummingbird Diversity” involving several researchers from across the country. Specifically my lab will measure the energetic response of hummingbird species in North and South American to climatic shifts as well as attempt to model how physiological constraints might impact future changes in hummingbird distributions. Our primary collaborators in this project will be Catherine Graham (SUNY Stony Brook; Lead Principle Investigator), Scott Goetz and Pieter Beck (Woods Hole Research Center), and Susan Wethington (Hummingbird Monitoring Network).
Hummingbird flight energetics and biomechanics
My lab is currently exploring questions associated with how a hummingbird’s unique anatomical design impacts the biomechanics of flight and the associated energetic cost. Our approach involves laboratory studies where flight conditions are controlled in a wind tunnel and field studies of hovering flight currently being conducted in southeastern Arizona. Recently we have expanded our laboratory work to include studies of heat balance during flight using high-speed infra-red imaging. Key collaborators in this work are Dr. Bret Tobalske, University of Montana, Dr. Doug Warrick, Oregon State University, and Dr. Susan Wethington, Hummingbird Monitoring Network.
Reproductive energetics of the red-sided garter snake (Thamnophis sirtalis parietalis)
In collaboration with Dr. Bob Mason and his graduate student Chris Friesen my lab is exploring questions associated with the reproductive energetics of red-sided garter snakes (T. sirtalis parietals) with specific interest in male-male competition for females and female energetic cost during courtship and copulation. We have conducted in the past experiments that explore how body size (male and female) and mating-group size impact reproductive costs. This past season our experiments explored the cost of male copulatory plug production contributes to a male’s energetic costs and how the cost of plug production might be impacted by male body size.. T. sirtalis parictalis is particularly interesting because of the high concentration of males that are competing for a few females when they emerge from hibernation.
The role of aquaporin water channels in amphibian water regulation
We are looking at questions associated with the how water transport in amphibians is managed through the regulation of aquaporin water channels (AQPs). We are specifically interested in Urodele amphibians and in particular the rough-skinned newt (Taricha granulosa). For the past two years we have used western blotting and immunofluorescence techniques to study the cellular distribution of AQP 1, 2, 3, and 4 in ventral skin, kidney, and intestine all of which play a role in water regulation. This past summer we have explored how AQPs are regulated during excessive dehydration. In the future we plan to begin experiments that will help us define the cellular signaling pathways used to control the number of AQPs in tissue membranes. A key collaborator in this work is Dr. John Schmitt who is also on the faculty at George Fox University.