Environment

Management of high sea fisheries could compensate losses due to climate change

New UBC study finds, a 10 percent increase in fish catches in coastal waters when high seas are closed off to fishing. This increase could help the most vulnerable cope with the expected losses of fish caused by climate change. “Many important fish stocks live in both the high seas and coastal waters. Effective management of high seas fisheries could benefit coastal waters in terms of productivity and help reduce climate change impacts,” said lead author William Cheung, associate professor and director of science of the Nippon Foundation-Nereus Program at UBC’s Institute for the Oceans and Fisheries. The high seas cover close to two-thirds of the ocean’s surfaces and are outside the jurisdiction of any country. By using computer models, researchers used three different management scenarios to predict catches of 30 important fish stocks in 2050, living in both the high seas and coastal waters. The three different scenarios were as followed: international cooperation to manage fishing, closing the high seas to fishing, and maintaining the status quo.

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By using computer models, researchers used three different management scenarios to predict catches of 30 important fish stocks in 2050, living in both the high seas and coastal waters.(Photo courtesy of: www.freeimages.com)

Strengthening governance and closing the high seas to fishing were found to increase resilience of coastal countries to climate change. This effect was especially noticed in tropical countries which are highly dependent on fisheries for food and livelihood. “The scenarios of closing the high seas may greatly reduce the issue of inequity of benefits and impacts among different countries under climate change,” said co-author Vicky Lam, a postdoctoral fellow at UBC’s Institute for the Oceans and Fisheries. Countries in the South Pacific, Indo-Pacific, West African coast and west coast of central America are expected to be disproportionately impacted by climate change. According to previous UBC studies, these countries could face a 30 percent decrease, if carbon dioxide levels continue to rise in a similar manner. This decrease would be due to the fish migrating to cooler waters. “The high seas can serve as a fish bank of the world by providing the insurance needed to make the whole global ocean more resilient,” said paper co-author Rashid Sumaila, professor at UBC’s Institute for the Oceans and Fisheries and director of OceanCanada, one of the research funders. “By closing the high seas to fishing or seriously improving its management, the high seas can help us mitigate and adapt to the effects of climate change on marine ecosystems.”