| Summary: | These data are part of the Gulf Watch Alaska (GWA), Pelagic Component of the Exxon Valdez Oil Spill Trustee Council, project numbers 12120114-M, 13120114-M, 14120114-M, 15120114-M and 16120114-M. Gulf Watch Alaska is the long-term ecosystem monitoring program of the Exxon Valdez Oil Spill Trustee Council for the marine ecosystem affected by the 1989 oil spill. This dataset is a number of comma-sepearetd values (csv) files which describe locations received from satellite tags deployed on killer whales in Prince William Sound and Kenai Fjords during the years 2004-2014. Locations were calculated by the ARGOS system, and the resulting output is listed in these .xls spreadsheets. The resident killer whale is a genetically and behaviorally distinct ecotype of killer whale (Orcinus orca) that feeds primarily on Pacific salmon (Oncorhynchus spp.). Details regarding habitat use have been inferred by boat surveys, but are subject to effort bias and weather limitations. To investigate use of habitat, 33 resident killer whales representing 14 pods in the Northern Gulf of Alaska were tagged with satellite transmitters from 2004 to 2014, and transmissions were received during the months of June to January. Core use areas were identified through utilization distributions using a biased Brownian Bridge movement model. Distinct shifts in these core use areas were revealed that are highly specific to season and pod. In June, July, and August, the waters of Hinchinbrook Entrance and west of Kayak Island were primary areas used, mainly by the AB, AI, and AJ pods. These same pods shifted their focus to Montague Strait in August, September, and October. Port Gravina was a focal area for the AD16 and AK pods in June, July, and August, but this was not the case in later months. AK and AD16 pods were responsible for seven of eight documented trips into the deeper fjords of Prince William Sound, though these fjords were not a focus for most groups. These temporal shifts in habitat use are likely a response to the seasonal returns of salmon, though details on specific migration routes and timing for these fishes are limited. We found strong seasonal and pod-specific shifts in patterns among core use areas. Future research should investigate pod differences in diet composition and relationships between core area use and bathymetry.
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