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Some fish are moving between the Atlantic and Pacific oceans. Credit: Monterey Bay Aquarium / TOPP
Many species of marine life are changing addresses. As the oceans get warmer, they’re moving to new waters to seek out comfortable temperatures. But quite a few species of fish could be about to make a really big move -- from the north Atlantic to the north Pacific or vice versa. That could mean big changes for the ecosystems of both regions -- and for the people that depend on them.
For the last several million years, the Arctic Ocean has been so cold that it’s been a barrier between the Atlantic and Pacific. As ocean temperatures rise, though, fish from both oceans have been poking farther into the Arctic.
A recent study says that a major migration could be under way by the middle of the century. Researchers studied the habits of more than 500 species of fish. They concluded that by 2050, as many as 41 species could migrate from the Atlantic to the Pacific, with 44 species going the other direction. And by 2100, the passages between the two oceans could be packed with migrating fish.
No one is sure what that will mean. When the Suez Canal opened, invasive species from the Red Sea basically took over the Mediterranean Sea. But when the Panama Canal opened, the exchange of species between the Pacific and the Caribbean did little damage to either ecosystem.
But since almost 40 percent of the world’s fish that go to market are caught in these two regions, one thing is clear: Life won’t be the same for either the fish or the people whose livelihood depends on them.
