On May 14, Northeast Fisheries Science Center staff finished the 2019 spring bottom-trawl survey aboard the NOAA Ship Henry B. Bigelow. Those aboard conducted resource survey tows and temperature and salinity sampling at 356 of 377 planned stations (95% completion); and plankton tows at 106 of 116 planned stations (91% completion.)
The spring survey occurs in four legs that range from 10 to 19 days long, beginning in the south and finishing in the north.
The survey got underway March 10, which was 6 days later than originally planned, a ripple effect from the January federal government shutdown. The wind and weather were comparatively mild and vessel operations were steady this spring, which helped make up for the time lost to the delayed start. The vessel encountered rough seas during some of Legs 3 and 4, but overall working conditions were favorable and sampling occurred over the full survey region. The survey’s third leg included Easter on Georges Bank.
The NOAA Ship Henry B. Bigelow supports a variety of marine research. However, the NEFSC’s multispecies bottom-trawl survey is the most important of its missions for monitoring the region’s fishery resources, and is the longest running of its kind in the world. Data collected are used to monitor the distribution and relative abundance of fish and invertebrate species on the continental shelf and upper slope of the Northwest Atlantic Ocean.
Temperature and salinity profiles collected during the survey help link fish distribution to physical oceanographic conditions. Ichythyoplankton (larval fish and eggs) collected help with understanding spawning distributions and with estimating changes in fish abundance. Zooplankton (tiny animals and immature stages or some larger ones) collected tell researchers about the ocean food web, and are used to construct models that support ecosystem-based fisheries management.