Gulf of Maine Cod Fishery Collapse Assisted by Warming Waters
Posted by feww on October 30, 2015
‘Slow adaptation in the face of rapid warming leads to collapse of the Gulf of Maine cod fishery’
Vital to New England’s fisheries, Atlantic cod is a key species in the Gulf of Maine ecosystem, say the authors of a new report released by the National Science Foundation (NSF).
Researchers used sea surface temperature data to establish temperature trends in the Gulf of Maine since 1982 and over the last decade (2004-2013) and found the Gulf of Maine had experienced unprecedented decadal warming.
The recent 10 year warming trend is remarkable, even for a highly-variable part of the ocean like the northwest Atlantic. Over this period, substantial warming also occurred off of western Australia, in the western Pacific, and in the Barents Sea; and cooling was observed in the eastern Pacific and Bering Sea. The global ocean has a total area of 3.6 x 108 km2, yet only 3.1 x 105 km2 of the global ocean had warming rates greater than that in the Gulf of Maine over this time period. Thus, the Gulf of Maine has warmed faster than 99.9% of the global ocean between 2004 and 2013. Using sea surface temperatures from 1900-2013, the likelihood of any 2° by 2° segment of the ocean exceeding this 10-year warming rate is less than 0.3%. Based on this analysis, the Gulf of Maine experienced decadal warming that few marine ecosystems have encountered.
The cod stocks today are on the verge of collapse estimated at only 4% of sustainable yield.
The most recent assessment found that SSB in this stock is now less than 3,000 mt, only 4% of the spawning stock biomass that gives the maximum sustainable yield (SSBmsy).
The report is posted at http://www.sciencemag.org/content/early/2015/10/28/science.aac9819.full