March 9, 2022 — Unlike boundaries on the land, the ocean is contiguous — fish move and transcend international waters as they please, without bothering about jurisdictions. As long as ocean temperatures remain generally stable, the fish remain in their known habitats and all is well. But as climate change heats up oceans rapidly, fish are on the move, upsetting fishing treaties between nations that stipulate who can catch how much fish in shared waters.
“Many of the fisheries management agreements made to regulate shared stocks were established in past decades, with rules that apply to a world situation that is not the same as today,” Juliano Palacios-Abrantes, a marine biologist at the University of Wisconsin-Madison, said in a press release.
In a recent study, Palacios-Abrantes and his colleagues from Canada, the U.S., U.K. and Switzerland predict that about half of the world’s commercial fish in shared waters will move from their known habitats by the end of the century. Published in the journal Global Change Biology, the study warns of a dramatic change in fish stocks by as early as 2030 that could lead to international disputes in exclusive economic zones, the area within 200 nautical miles (370 kilometers) of a country’s coast where it has exclusive rights for fishing.
By 2030, according to the study, climate change will force 23% of shared fish stocks to move from their historical habitats and migration routes, if nothing is done to halt greenhouse gas emissions. By the end of the century, that number could rise to 45%.