Between 3--14 July 2016, researchers from the National Marine Fisheries Service/Marine Mammal Laboratory conducted harbor porpoise research in the inside waters of Southeast Alaska. The main objective was to collect genetic material to assess harbor porpoise "stock structure". The Marine Mammal Protection Act defines a stock as "a group of marine mammals of the same species or smaller taxa in a common spatial arrangement that interbreed when mature." Two areas of porpoise concentrations have persisted throughout our long-term studies (1991 through 2016). These include the waters of both Glacier Bay/Icy Strait and the waters surrounding Wrangell/Zarembo Islands and Sumner Strait.
In 2015, we conducted a pilot project to evaluate whether or not we could obtain genetic material from harbor porpoise fluke prints (i.e. water samples). This "environmental DNA" (eDNA) method proved successful and porpoise DNA was collected. Given the success of this pilot project, we opted to continue this research. During July 2016, we obtained 22 porpoise water samples from the Wrangell/Zarembo Islands area and 33 samples from the Icy Strait area. These samples will be analyzed with the hope of understanding gene flow between harbor porpoises within Southeast Alaska and beyond.
Another porpoise survey is planned for September 2016. For more information, please contact Dr. Marilyn Dahlheim (marilyn.dahlheim@noaa.gov) at 206/526-4020.