For centuries, cod were the backbone of New England's fisheries and a key species in the Gulf of Maine ecosystem. Cod is a cold-water species, and the Gulf of Maine is at the edge of its geographic range. As the ocean warms, the capacity of the Gulf of Maine to support cod will decline, leading to a smaller population and a smaller fishery, according to hypotheses.
Today, cod stocks are on the verge of collapse, hovering at 3-4 percent of sustainable levels. Even painful cuts to the fishery have failed to slow this rapid decline, surprising both fishers and fisheries managers. A new report in Science links the cod collapse directly to rapid warming of ocean waters.