Mordy, C.W., E. Cokelet, A. DeRobertis, R. Jenkins, C. Meinig, C. Berchok, J. Crance, J. Cross, C. Kuhn, N. Lawrence-Slavas, P. Stabeno, J. Sterling, H. Tabisola, and I. Wangen (2017): Advances in ecosystem research: Saildrone surveys of oceanography, fish and marine mammals in the Bering Sea. Oceanography, 30, 2, doi:10.5670/oceanog.2017.230.
This month's featured article provides an overview of the first Saildrone mission conducted jointly between NOAA Fisheries Alaska Fisheries Science Center (AFSC) and Pacific Marine Environmental Laboratory (PMEL).
The Saildrone is an autonomous surface vehicle outfitted with meteorological and oceanographic sensors, including passive and active acoustics. In 2016, NOAA used the Saildrone to survey the Bering Sea, a region known for its harsh conditions (e.g., storms, low light, biofouling) and high level of biological productivity. The mission was a success, and the Saildrone proved to be effective at augmenting historical walleye pollock surveys, listening for critically endangered whales, and surveying fish abundance while northern fur seals were eating in near-real time.
The innovative platform performed well and demonstrated its potential to advance ecosystem research. Cross-comparison of sensors between the Saildrone from a known mooring site and the NOAA Ship Oscar Dyson show that the Saildrones provide high-quality meteorological and oceanographic data. On two occasions, NOAA Ship Oscar Dyson trailed behind a Saildrone to compare active acoustic systems under varying weather conditions.
Notable findings from this mission:
Net fishing sampling from NOAA Ship Oscar Dyson confirmed, as in previous years, that the acoustically detected activity on the outer shelf in 2016 was almost entirely attributable to walleye pollock, with older fish distributed closer to the seafloor.
Despite complications from ubiquitous hull-slapping noise, analysis of the approximately 5,150 hours of marine mammal recordings collected revealed the presence of killer whales and humpbacks, with possible detections of a right whale and fin whale.
Initial survey results suggested that differences in prey distributions may influence northern fur seal foraging behavior, and demonstrated that they prey on both small and large pollock.
Three Saildrones are currently in operation in the Bering and Chukchi seas. You can follow these Saildrones on the mission blog.
Read more about the northern fur seal work at AFSC: Dispatches from the Field blogs, 'Northern fur seal food study in Bering Sea using Saildrone: Second year adding video'. You can also learn more about the 2016 field season, 'Understanding northern fur seal relationship with prey key to conservation'.