Robust Reserve

A decade ago, the waters of Cabo Pulmo off of Baja California in Mexico had been hammered by overfishing. Now, thanks to local backing of a national park with strict “no take” rules, fish populations have soared, according to the results of a long-term study.

“We could have never dreamt of such an extraordinary recovery of marine life at Cabo Pulmo,” says National Geographic Explorer-in-Residence Enric Sala, who started the study in 1999. Then, “there were only medium-sized fishes,” he recalls. Now, “it’s full of large parrotfish, groupers, snappers and even sharks.”

For 10 years, a team of scientists has been monitoring the Gulf of California’s rocky reefs every year, sampling more than 30 islands and peninsula locations along Baja California. And since the 71-square-kilometer Cabo Pulmo National Park (CPNP) was established in 1995, fish communities have rebounded to sizes typically found at far less exploited sites. In particular, the total amount of fish found in the reserve ecosystem (the “biomass”) boomed more than 460 percent between 1999 and 2009, they report in PLoS ONE.

“No other marine reserve in the world has shown such a fish recovery,” says Octavio Aburto-Oropeza, lead author of the study and a postdoctoral researcher, at the Scripps Institution of Oceanography at the University of California, San Diego.

The success is the result of a range of action, the authors note, including protection of spawning areas for large predators, and determined enforcement of conservation rules by local families and boat captains. If you visit the place now, you cannot believe the change that has taken place,” says study co-author Exequiel Ezcurra, Director of the University of California Institute for Mexico and the United States (UC MEXUS. “Coastal villagers decided to take care of their place and to be at the helm of their own destiny.”

“Few policymakers around the world are aware that fish size and abundance can increase inside marine reserves to extraordinary levels within a decade,” says Aburto-Oropeza. “Showing what’s happened in Cabo Pulmo,” he hopes, “will contribute to ongoing conservation.”David Malakoff | August 14, 2011

Source: Aburto-Oropeza O, Erisman B, Galland GR, Mascareñas-Osorio I, Sala E, et al. (2011) Large Recovery of Fish Biomass in a No-Take Marine Reserve. PLoS ONE 6(8): e23601. doi:10.1371/journal.pone.0023601

Image Octavio Aburto-Oropeza/iLCP