Gulf Apex Predator-Prey Project
Kodiak Seafood and Marine Science Center
University of Alaska Fairbanks • School of Fisheries and Ocean Sciences • Kodiak, Alaska

GAP 2010

The role of balaenopterids in structuring Kodiak's marine ecosystem

Project Summary

In GAP 2010 our goal is to take a top-down approach to exploring the impact of balaenopterids on the nearshore marine ecosystem that includes waters of Kodiak and the western Gulf of Alaska. Broadly, we propose to identify and quantify (where possible) the ecosystem processes, drivers, sensitivities, and variability that affect these whale populations and their prey. Specifically, we will use empirical data (when available) to explore the ecological role of humpback and fin whale foraging in Kodiak’s nearshore waters and model potential trophic-level responses to changes in their abundance, diet, and/or consumption rate. From this we will examine the secondary and tertiary effects of those changes on potential prey populations and changes in carrying capacity (K) for other intermediate and upper level consumers. To do so we will rely on a combination of collaboration, synthesis, modeling, and monitoring.

Our objectives are to

  1. Identify existing oceanographic and biological data sets available within western Gulf of Alaska (and potential surrogates) and compile GAP-related research into an accessible meta-database
  2. Develop models using those available data to explore the impact of changes in baleen whale population size and diet on
    1. juvenile fish survival
    2. biomass removal of zooplankton and forage fish
    3. K for key species at the same trophic level (pollock, seabirds, salmon, Pacific cod, arrowtooth flounder)
  3. K for key species in next higher trophic level (Steller sea lion, harbor seal, human harvesters)
  4. Continue monitoring seasonal abundance and diet of Kodiak’s balaenopterids to refine future iterations of the model