| Summary: | These data are part of the Prince William Sound Herring Survey Program (EVOS project number 10100132-G), of the Exxon Valdez Oil Spill Trustee Council which is a multi-faceted study to determine why herring populations in Prince William Sound remain depressed since the early 1990s. Our fish predators on juvenile herring project dataset is 11 comma-separated values (csv) files exported from a Microsoft Access database with a graphical relationship chart. The original dataset is also provided in Microsoft Acces(.acdb format). The data contain measurements of fish predator abundance and distribution in relation to juvenile herring in a series of bays in Prince William Sound during the 2009/10 through 2011/12 winters. Specifically, fish collections took place during November and March over three winters, beginning in November 2009 and ending March 2012. We deployed 79 longline sets including 61 sets at the five core bays (Eaglek, Lower Herring, Simpson, Whale, and Zaikof). Longlines were set near schools of herring located during hydroacoustic surveys conducted the previous day. For all six cruises we supplemented information on potential predators using variable-mesh gill nets placed perpendicular to shore. For each cruise, we collected up to 30 individuals of each species captured from the combined longline and gill net sets in the sampled bay. Fish were measured (TL, mm) and weighed (g) prior to removal of stomachs for dietary analyses. Stomach contents were analyzed in the laboratory to determine diet composition. Gut contents were sorted into gross taxonomic categories, enumerated and weighed (g). All fish prey items (fish tissue, otoliths and bones such as jaws, vertebrae, etc. as well as partially and fully intact fish prey) were shipped to a second laboratory. There fish were identified to species, estimated to size from hard parts based on published regressions, and counted.
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