An eclectic team of investigators is attempting to construct a high-resolution map of cod spawning on Stellwagen Bank.

South Shore fishermen, alarmed by the downward trend in cod take, approached The Nature Conservancy (TNC) for help. Although the season and area of code spawning in Massachusetts Bay is known in a broad sense, a widespread closure could be ruinous to the local industry. But a high-resolution spawning map, in space and in time, might allow for small, targeted closures to protect spawning while permitting fishing to continue as the stocks rebuild.

TNC responded to the fishermen by assembling a diverse team of federal, state, academic and Conservancy scientists to tackle the problem.

At a press conference last week, participating fishermen and representatives of TNC, the state’s Department of Fish and Game and Division of Marine Fisheries, NOAA’s Northeast Fisheries Science Center, and UMass Dartmouth’s School for Marine Science and Technology outlined the plan. Bottom mounted hydrophones will record the time and extent of the pronounced vocalizations that cod make during spawning. Meanwhile, acoustic transducers will record the movements of some 150 mature cod that have been electronically tagged over the past month or so. Researchers hope to integrate the data to zero in on the when and where of cod spawning in Mass Bay.

“This project has been a unique and successful collaboration between the fishing industry and scientists from multiple institutions,” said SMAST PhD student Doug Zemeckis, who is leading the tagging effort. “The information acquired from acoustic telemetry, passive acoustic monitoring, and at-sea sampling will be helpful for informing future fishery management decisions to help rebuild the resource and the cod fishery.” Read more.

Photo courtesy John Clarke Russ/TNC.