Scientists Develop Video Fish Counting System

Scientists at the UMass School for Marine Science and Technology are reporting a major advance in a new technology to use video to survey the fish stocks in the fishing grounds of the North Atlantic.

Dr. Kevin Stokesbury’s team surveyed the entire Stellwagen Bank, a fishing ground in the Gulf of Maine about 15 miles south of Gloucester and 6 miles north of Provincetown. They found large numbers of cod, whose stock assessments have been sharply reduced in recent years because of surveys done by NOAA fisheries. The reduction has caused a chain reaction in the fishing industry as abundant species cannot be caught if too much cod is hauled in as bycatch.

Four years in the making, Stokesbury’s video apparatus has now been equipped with high-resolution video that enables the identification of every fish that passes through the open-ended trawl net used to count fish without harming them.

“The seven-day cruise was very successful,” Stokesbury said in a news release. “Atlantic cod were observed over much of the bank, and the largest tow collection was of 345 cod in a half hour, with individuals measuring up to 83 centimeters. The idea is to increase the amount of sea floor sampled per sea day without killing more fish.”

The big improvement over past versions of the video apparatus is the addition of a GoPro camera that enables the identification of every fish in high definition. Prior versions relied entirely on a tethered black and white video camera.