UD researcher examines nations losing fish species due to climate change

As ocean warming causes fish stocks to migrate toward cooler waters to maintain their preferred thermal environment, many of the nations that rely on commercial fish species as an integral part of their economy could suffer.

A new study published in Nature Sustainability from the University of Delaware, the University of California, Santa Barbara and Hokkaido University, shows that nations in the tropics — especially Northwest African nations — are especially vulnerable to this potential species loss due to climate change. Not only are tropical countries at risk for the loss of fish stocks, the study found there are not currently any adequate policy interventions to help mitigate affected countries’ potential losses.

Kimberly Oremus, assistant professor in the School of Marine Science and Policy in UD’s College of Earth, Ocean and Environment, explained that when the researchers looked at international agreements, including the United Nations Convention on the Law of the Sea, they found no specific text for what happens when fish leave a country’s Exclusive Economic Zone (EEZ), a zone established to give a country national jurisdiction over a fishery resource.

​That means countries could be vulnerable to economic losses, and those potential losses could make the fish populations themselves vulnerable as well.

​“We realized there was an incentive for countries when they lose a fish or anticipate that loss to go ahead and overfish before it leaves because otherwise, they don’t get the monetary benefits of the resource,” said Oremus.