A study by a group of researchers led by Dr. Andrew J. Pershing from the Gulf of Maine Research Institute appeared in Science last November (“Slow adaptation in the face of rapid warming leads to collapse of the Gulf of Maine cod fishery”). The Pershing study concluded that fisheries managers overseeing Gulf of Maine cod failed to consider ocean temperature in their management strategies, leading to overfishing of the stock.
This week’s issue of Science published comments from two groups of scientists critiquing the Pershing study and its conclusions. In the same issue, the Pershing team responded with a defense of their work. Summaries of the comments and response are provided below:
A group of researchers at the Population Dynamics Branch of the Northeast Fisheries Science Center, led by Dr. Michael C. Palmer, argues that the Pershing study’s claim that rising temperatures led to “extra mortality” is unsubstantiated by the overall mortality data. While Palmer’s group agrees that environmental factors affect fish stocks, they argue that the Pershing study failed to attribute additional mortality to temperature alone. Consequently, they conclude, “The analyses of Pershing et al. provide no evidence to support the hypothesis that failure to account for increases in temperature led to overfishing of the Gulf of Maine Atlantic cod stock.”