Acoustic-Trawl surveys provide critical input to fisheries management. They are traditionally undertaken using an echo-sounder on a research ship.
Pictured right, is one of NOAA's Fisheries Survey Vessels the Oscar Dyson, alongside a Saildrone in the Bering Sea in 2015. FSV's like the Oscar Dyson perform acoustic transects over large areas of the ocean to produce fish abundance estimates.
"Fish stock assessments are key to the sustainable management of our fisheries and provide the best scientific information available to determine the status of fish stocks. They guide the setting of annual catch limits (ACLs) that prevent over fishing and attain optimum yield from our fisheries." (NOAA 2015)
Saildrone has worked closely with SIMRAD, part of the Kongsberg group, and PMEL, to incorporate the very latest acoustic fish stock assessment device (wide band transceiver) onto the Saildrone platform. Additional trials and inter-comparisons with the Oscar Dyson were conducted throughout summer 2016 in the Bering Sea.
Acoustic-Trawl surveys from Saildrone Unmanned Surface Vehicles (USVs) augmenting Fisheries Survey Vessels have the potential to reduce the number of ship days required per assessment and allow additional sampling of currently under-sampled areas.
Saildrone operating with the Oscar Dyson in the Bering Sea, Summer 2015.
Map of acoustic backscatter attributed to walleye pollock along tracklines during an Oscar Dyson acoustic-trawl survey of walleye pollock in the vicinity of Shelikof Strait in the Gulf of Alaska.
Data from the onboard WBT mini (EK80) 38kHz Frequency in deep water,
showing good signal down to the sea floor @ 900m.