Rising ocean temperatures are driving major changes in fisheries throughout western Europe, bringing warm water species typically seen in the Mediterranean to the coast of the United Kingdom.
A new report card issued by European marine researchers details the ecological and economic impact that climate change is having on fisheries in the UK and Scotland — concluding that there are “clear indications that climate change is affecting fish stocks” in the region.
The report card features a map of changes currently underway. In southwest England, there are increases in blue fin tuna, triggerfish, thresher sharks, stingrays, and ocean sunfish; In the North Sea, fisherman are catching far more squid, shifting from a traditional focus on haddock and cod; and on the coast of eastern England, fisherman are seeing major declines in cod due to overfishing and changing temperatures.
A rise in ocean temperatures could have mixed results in Europe, wiping out some fish stocks and making others more abundant. But the net impact would be unquestionably bad, warn the researchers:
Projected global redistributions of fish will affect different parts of the world unequally. By 2050, tropical regions could experience significant declines in landings with gains in some high latitudes. The overall cost of adaptation of the fisheries sector worldwide in response to climate change is predicted to be large and could lead to losses in gross fisheries revenues of $10–31 billion by 2050.
If ocean temperatures rise by 1 degree Celsius, the report predicts that mussel harvests could fall by half, while increasing storms could damage salmon farms — potentially introducing new predators or causing farmed salmon to escape in the wild and hybridize wild stocks.
The report card was put together by Marine Climate Change Impacts Partnership, a group of scientists from government agencies and NGOs. While some of the long-term predictions for fisheries are sketchy, the impacts today are already being seen: “There are clear changes in the depth, distribution, migration and spawning behaviours of fish — many of which can be related to warming sea temperatures.”