Last week, the National Observer reported that lobsters off the Atlantic coast of North America are moving northward, decimating the New England lobster fishery.
A few weeks earlier, the Wall Street Journal reported on a similar trend among many Atlantic fish stocks, including red hake and summer and yellowtail flounder.
Throughout the world’s oceans, fish populations are moving poleward as climate change causes water temperatures to increase. And the migration has profound implications for ecosystem health and the fishing industry.
UBC has been on the frontlines of research into the effects of climate change on fisheries. Last month, UBC marine biologist Daniel Pauly spoke about the northward migration of fish stocks at the FACTS Biodiversity and Innovation conference, held at the university.
“These fish that move toward the poles, they carry with them a catch potential,” he said. “And if you take . . . the movement of catch potential, you see that the tropical belt will lose catch potential. And it will lose catch potential because the fish that are leaving the tropics are not being replaced by other fish.”
Back in 2013, Pauly and his colleagues published a paper in the scientific journal Nature showing that climate change had already been driving fish species to cooler, deeper waters for the previous four decades.
And more recent research shows that this large-scale migration could have significant impacts on B.C. communities.
In January, a new study led by former UBC graduate student Lauren Weatherdon found that B.C. coastal First Nations could see their fisheries’ catch decline by nearly 50 per cent by 2050, which could lead to economic losses of between $6.7 and $12 million annually.
Of course, some Canadian fisheries stand to benefit from the northward migration of more southerly fish. The National Observer reported that lobster fisheries in Nova Scotia and Prince Edward Island are booming, while Rhode Island, Connecticut and New York suffer.
But migrating fish species can also pose a serious threat to Arctic fish populations that don’t have the ability to expand their own ranges northward.
A 2015 paper in Nature Climate Change found that Arctic fish in the Barents Sea are retreating to the northernmost parts of the sea as cod, haddock and other Atlantic fish moved in from the south.
And warmer temperatures aren’t the only product of climate change that is affecting fisheries. Ocean acidification, caused by the oceans absorbing man-made carbon dioxide, is threatening many marine organisms, particularly shellfish and corals.
Finding a way to address these changes will certainly not be easy. But in his recent presentation, Pauly said an important place to start is to replace large-scale fisheries with smaller-scale, local industries.
“The large-scale fisheries, they induce too strong a pressure on the resource,” he said. “Sustainability is . . . being able to do what you do all the time. And only small-scale fisheries can do that.”
By Maura Forrest, June 8, 2016