Fall and Winter Seabird Abundance Data, Prince William Sound, 2007-2024, Gulf Watch Alaska Pelagic Component

This dataset contains marine bird observation data in Prince William Sound (PWS) from 2007-2022. The dataset includes 16 comma-separated value (csv) files exported from the marine bird and mammal observation software dLOG (Ford Consulting, Inc., Portland OR 1999; 2007 - March 2021) and SeaLog (ABR, Inc; September 2021-present) for each winter the survey was conducted. Depending on the winter and project, marine bird observations were collected in September, October, November, December, January, February, or March. In the 2006/07 and 2022/2023 seasons, data were collected only during March (2007, 2023). These data began as part of the restoration programs of Exxon Valdez Oil Spill (EVOS) Trustee Council's Herring Program (2007-2011) and Gulf Watch Alaska (GWA) Pelagic Component (2012-2016, 2017-2022). The EVOS Herring Program is a multi-faceted study to determine why herring populations in PWS remain depressed since the early 1990s. GWA is the long-term ecosystem monitoring program of the EVOS for the marine ecosystem affected by the 1989 oil spill. Data were collected under multiple projects each with different objectives. In March 2021 and 2022, the survey was expanded and partially funded by the Prince William Sound Regional Citizens' Advisory Council. Beginning in March 2023, the PWS Regional Citizens' Advisory Council became the sole funder of the March seabird survey, which then shifted to September and November surveys in 2024. GWA remains a funder of annual surveys in September. Refer to funding chronology under Supplemental Information for project-specific objectives. All marine bird observations were conducted using established U.S. Fish and Wildlife Service (USFWS) protocols (USFWS 2007). Except for the March 2007 survey, all surveys record number of birds sighted by observers within a strip transect width of 300 m (150 m both sides and ahead of the boat, in 3 distance bins of 50 m) made by a research vessel. In March 2007, the strip-width was 200 m. The observer recorded observations into a laptop computer integrated with a global positioning system (GPS) using the program Dlog (2007 - March 2021) or SeaLog (September 2021- onward). These GPS-integrated programs provided location data at 15-sec intervals and for every entered observation. Because surveys were conducted in conjunction with different research programs, observations were typically conducted under one of two scenarios: while boats were transiting between areas or, in the case of juvenile herring surveys, observations were conducted in juvenile herring survey bays along a zigzag track, approximately 200 m or greater from shore that coincides with the same transect line as the nocturnal hydroacoustic juvenile herring surveys. In the later years, the project expanded from placing bird observers on-board EVOS-sponsored PWS Science Center juvenile herring surveys and NOAA Humpback Whale surveys to include two additional ships of opportunity as observation platforms. These include: Alaska Department of Fish and Game spot-shrimp cruise and the Ocean Tracking Network maintenance cruise.