| Summary: | These data are part of the Gulf Watch Alaska (GWA), Pelagic component of the EVOSTC, project numbers, 10100804, 090804, 080804, 070804, 12120114-N, 13120114-N, 14120114-N, 15120114-N, and 16120114-N. 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. The impact by humpback whales on Pacific herring (Clupea pallasi) populations in Prince William Sound (PWS) were evaluated in this study. Pacific herring in PWS have been classified as "not-recovered" by the Exxon Valdez Oil Spill Trustee Council (EVOSTC). Predation by marine mammals has been cited as a factor in the failure of this population to rebound. Following protocols established during the winters of 2007/08 and 2008/09(EVOSTC project PJ090804), the seasonal trends and abundance of humpback whales (Megaptera novaeangliae) in PWS were examined from 2012 to 2016. Prey selection by humpback whales was determined through acoustic surveys, visual observation, scat analysis and prey sampling. Chemical analysis of blubber samples (stable isotopes and fatty acid analysis) were collected to provide a longer term perspective on whale diet and shifts in prey type. These data will be combined in a bioenergetic model to determine numbers of herring consumed by whales, with the long term goal of enhancing the age structure modeling of population with better estimates of predation mortality. The native file format is a Microsoft Office Access 2007 database (12.0 6735.5000) containing the humpback whale surveys including survey effort, whale identification, photo quality, whale behavior, prey items and tissue samples. For archive, the Access database was converted to 59 comma-separated values (csv) files and 1 JPG file of the data provider's original data to ensure that the information contained within the Access database file is openly accessible to data customers.
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