Cooperative Fish and Wildlife Research Units Program: Utah
Education, Research and Technical Assistance for Managing Our Natural Resources

Arctic lakes support trophic interactions, biological processes, and critical habitat at all trophic levels; however, climatic warming threatens to alter the structure and function of aquatic communities and overall system production. Arctic ecosystems are warming at some of the fastest rates observed on earth, and arctic lakes are experiencing more frequent years of warmer surface water and deeper mixing. However, the ability to detect and quantify ecosystem effects and specific biological responses (e.g. bacterial diversity, invertebrate production, fish growth) to these climatic changes has been primarily limited to non-mechanistic modeled scenarios and observational studies in uncontrolled environments. The proposed research will use a controlled whole-lake manipulation experiment to answer: How will warmer lake temperatures and extended growing season alter (1) lake ice coverage and annual thermal regime, (2) abundance, activity and diversity of primary and secondary producers, (3) fish vital rates and dynamics, and (4) degree of carry-over across growing seasons and cumulative effects on ecosystem production. The project is a collaboration of researchers across multiple academic entities including Oregon State University and the Marine Biological Lab, Woods Hole, MA. This research will quantify lake thermal processes and lake-atmosphere feedbacks, provide more precise projections of lake horizontal and vertical temperature structures, and document and
predict lake biota and ecosystem responses to lake thermal condition changes under different climate scenarios. By providing some of the first empirical evidence of how fundamental processes will actually change in the face of climate change, this research will also improve understanding of ecosystem service sustainability (e.g., subsistence fisheries).