CastAway CTD Data: 2017-2019 and 2021-2024, Gulf Watch Alaska Pelagic Component, Long-term Monitoring of Humpback Whale Predation on Pacific Herring in Prince William Sound

These data are part of the Gulf Watch Alaska (GWA) Pelagic component, which is a long-term ecosystem monitoring program of the Exxon Valdez Oil Spill Trustee Council (EVOSTC) for the marine ecosystem affected by the 1989 oil spill. As part of a larger study of humpback whale (Megaptera novaeangliae) impact to Pacific herring (Clupea pallasi) populations in Prince William Sound (PWS), CTD surveys were conducted as part of an integrated fall/winter predator-prey survey.

Vessel surveys in Prince William Sound (PWS) were conducted twice per year during the spring and fall months to record Conductivity, Temperature, and Depth (CTD) measurements. The surveys were timed to coincide with the movement of whales into the PWS. The surveys visited PWS bays that have historically been used by whales and herring to maintain ongoing EVOSTC funded long term monitoring surveys for humpback whales.

The dataset is presented as .zip file containing collections of CSV files by study year from 2017-2019 and 2021-2024 for different survey locations. A field season in 2020 was cancelled due to the COVID-19 pandemic. The individual CTD files are named: __< Cast time in UTC > location . The files contain pressure, depth, temperature, conductivity, conductance, salinity, sound velocity, and density for each CTD cast. Instrument metadata is contained in the header file.