Banning Fishing at Revillagigedo National Park Works

Banning fishing in the 57,000-square-mile Revillagigedo national park in Mexico's Pacific Ocean did not reduce the nation's fishing catch, dispelling the "myth" spread by fishing companies that banning fishing would leave less fish available for people to eat. The park, a favorite of scuba divers, is loaded with manta, tuna, sharks, and other big fish.

Before fishing in the Marine Protected Area was banned in 2017, Mexico's $1 billion fishing sector had warned it could reduce their catch of tuna and other pelagic fish by 20 percent. But catch data comparisons from the four years before and after the ban showed the MPA "had no causal effect on catches or area use, and, therefore, did not cause harm [to the Mexican fishing fleet]," said Fabio Favoretto, lead author of a new study published in the journal Science Advances.

One "high speculative" conclusion might be the existence of more fish in the areas around, as well as inside, MPAs, caused by a "spillover effect" into the surrounding seas, Favoretto said, adding that the research team aimed to look at this issue in its next study.

During the four years, illegal fishing was minimal and dropped to zero once a specialized marine crime monitoring program was fully implemented in 2021.

The idea that MPAs might mean more, not less, fish for fleets is not new, said Enric Sala, one of the study's co-authors. "It's a myth that we can't protect more of the ocean because we need more fish to feed more people. The global fishing catch has been declining since the mid-'90s, yet only three percent is protected from fishing. The worst enemy of the fishing sector is not protected areas. It's overfishing."

This is an edited version of an article written by Sophie Kevany that appeared in theGuardian.org on June 1, 2023