In my position as Lead Marine Mammal Researcher in the Wildlife Program at the Washington Department of Fish and Game, I coordinate and carry out research in support of wildlife management and conservation efforts by the State. Through collaborations with Federal, Tribal, academic, and non-profit organizations, our group conducts a variety of field- and laboratory-based investigations including abundance estimation, diet analysis and bioenergetics, and habitat use by Washington's pinnipeds and cetaceans.

      As a postdoctoral scholar at the Cooperative Institute for Climate, Ocean, and Ecosystem Studies (CICOES, formerly JISAO) at the University of Washington, I worked to develop new tools for studying marine mammal biology, physiology, and life history using concentrations of trace elements in teeth. A primary goal of this work was to create a new tool for wildlife conservation and management. This research relied on specimens from animals harvested by Alaska Native subsistence hunters, and involved collaborations with researchers at the University of Alaska Fairbanks, the University of Alaska Museum, Alaska Department of Fish and Game, and the North Slope Borough Department of Wildlife Management.

      As a postdoc in the Water and Environmental Research Center at the University of Alaska Fairbanks, I developed an R package for applying Suess and Laws corrections to stable carbon isotope (δ¹³C) data from marine systems. Burning of fossil fuels since the Industrial Revolution has substantially changed the stable carbon isotope ratios of the atmosphere and oceans. This baseline shift is translated into marine foodwebs as phytoplankton incorporate aqueous CO₂ into their cells during photosynthesis. This shift in baseline stable carbon isotope values makes comparison of δ¹³C data across broad time periods problematic. Because the release of anthropogenic CO₂ into the atmosphere has been increasing exponentially, comparison of δ¹³C data collected across as short a span as a single decade may be shifted by an amount equal to or greater than the instrument error typically reported in stable isotope studies (~0.2‰). SuessR applies two region- and year-specific corrections to δ¹³C data. The Suess correction itself deals only with the change stable carbon isotope ratios of the CO₂ dissolved in the oceans. The Laws correction accounts for changes in fractionation of carbon isotopes by phytoplankton associated with increased water temperatures, aqueous CO₂ concentrations, etc. In its current state, the SuessR package applies both Suess and Laws corrections for the Gulf of Alaska, the Aleutians, and the Bering Sea. Work on the SuessR package is ongoing, and more regions will be added in the future. To check out the SuessR package, click on the Shiny and/or GitHub links below or run the following code in R (requires the devtools package):

devtools::install_git("https://github.com/ctclark/SuessR")