Using otolith geochemistry to understand the ocean ecology of a changing Alaskan salmon system
EMSL Project ID
51783
Abstract
Overview. The goal of this project entitled is to relate otolith ?18O and ?13C isotope variability during ocean residency of adult sockeye salmon (Oncorhynchus nerka) returning to the Copper River, Alaska, over a 17-year period (2004-2020) to a suite of environmental variables that capture signals of ocean-climate and density-dependent factors operating in the North Pacific Ocean, as well as population performance traits of sockeye including adult body size and body condition. Time series analysis will be used to formalize relationships between environmental drivers and responses by Copper River sockeye to advance the general knowledge of high latitude marine ecosystem response to rapid and unprecedented levels of environmental change, as well as the scientific information needed to inform the long-term sustainable management of this key Alaskan salmon system.Intellectual Merit. Between 2014-2016, the eastern sector of the North Pacific Ocean including the Gulf of Alaska (GOA) experienced one of the largest marine heatwaves ever recorded. Responses by southcentral Alaskan salmon stocks to these anomalous ocean-climate conditions in the GOA, and other density-dependent environmental changes related to the release of significant numbers of hatchery pink salmon to the GOA, have been highly variable and range from record returns by Prince William Sound pink salmon in 2015 to run failures by these same stocks in 2016, as well as run failures by sockeye salmon returning to the nearby Copper River system in 2018. Thus, Pacific salmon of the GOA appear to be responding to recent, highly anomalous environmental changes, however, environmental driver and salmon response relationships have not been formalized. The research described in this proposal will fill this knowledge gap.
Broader Impacts. This project will forge new partnerships with collaborators, Dr. Tim Linley a research ecologist at the Pacific Northwest National Laboratory (PNNL, the host site) – a United States Department of Energy research and development center located in Richland, WA, and Stormy Haught a fisheries research biologist with Alaska Department of Fish and Game located in Cordova, AK who has access to an otolith library for Copper River sockeye dating back to 2004. This project would not be possible without these new partnerships. During the fellowship, the project’s PI (Dr. Kristen Gorman, research faculty in the College of Fisheries and Ocean Sciences at the University of Alaska Fairbanks[UAF]) will spend three months during the first year of the award working in Dr. Linley’s lab at the PNNL host site to conduct otolith ?18O and ?13C isotope analysis. The remaining three months of the fellowship will be focused on data analysis using time series methods, manuscript preparation, and presentation of results at an international conference. The NSF Directorate, Division, and Program that most closely aligns with this proposal's research focus is Geosciences, Ocean Sciences, and Biological Oceanography.
Project Details
Start Date
2020-11-18
End Date
2021-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)