Tag Archives: Mexico

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World’s Most Robust Marine Reserve is at Baja California

A thriving undersea wildlife park tucked away near the southern tip of Mexico’s Baja peninsula has proven to be the most robust marine reserve in the world, according to a new study led by researchers at Scripps Institution of Oceanography at UC San Diego.

Results of a 10-year analysis of Cabo Pulmo National Park (CPNP), published in the Public Library of Science (PLoS) ONE journal, revealed that the total amount of fish in the reserve ecosystem (the “biomass”) boomed more than 460 percent from 1999 to 2009. People living around Cabo Pulmo, previously depleted by fishing, established the park in 1995 and have strictly enforced its “no take” restrictions.

“The study’s results are surprising in several ways,” said Octavio Aburto-Oropeza, a Scripps postdoctoral researcher, World Wildlife Fund Kathryn Fuller fellow and lead author of the study. “A biomass increase of 463 percent in a reserve as large as Cabo Pulmo (71 square kilometers) represents tons of new fish produced every year. No other marine reserve in the world has shown such a fish recovery.”

The paper notes that factors such as the protection of spawning areas for large predators have been key to the reserve’s robustness. Most importantly, local enforcement, led by the determined action of a few families, has been a major factor in the park’s success. Boat captains, dive masters and other locals work to enforce the park’s regulations and share surveillance, fauna protection and ocean cleanliness efforts.

Strictly enforced marine reserves have been proven to help reduce local poverty and increase economic benefits, the researchers say. Cabo Pulmo’s marine life recovery has spawned eco-tourism businesses, including coral reef diving and kayaking, making it a model for areas depleted by fishing in the Gulf of California and elsewhere.

“The reefs are full of hard corals and sea fans, creating an amazing habitat for lobsters, octopuses, rays and small fish,” said Brad Erisman, a Scripps postdoctoral researcher and co-author of the article. “During some seasons thousands of mobula rays congregate inside the park and swim above the reef in a magnificent way.”

The scientists have been combining efforts to monitor the Gulf of California’s rocky reefs every year for more than a decade, sampling more than 30 islands and peninsula locations along Baja California, stretching from Puerto Refugio on the northern tip of Angel de la Guarda to Cabo San Lucas and Cabo Pulmo south of the Bahia de La Paz.

In the ten years studied, the researchers found that Cabo Pulmo’s fish species richness blossomed into a biodiversity “hot spot.” Animals such as tiger sharks, bull sharks and black tip reef sharks increased significantly. Scientists continue to find evidence that such top predators keep coral reefs healthy. Other large fish at Cabo Pulmo include gulf groupers, dog snappers and leopard groupers.

Sea of Cortez Threatened

Life in the Sea of Cortez is endangered by destructive new fishing methods.

Ten years ago graduate students Octavio Aburto-Oropeza and Gustavo Paredes surveyed the marine life of the Sea of Cortez (also known as the Gulf of California). In 2009 they went back and were shocked at how things had declined. Sixty percent of the surveyed sites showed signs of degradation, according to Aburto-Oropeza, and many are now missing the top predators normally present in healthy, functioning ecosystems.

“Ten years later we can actually measure the effects of not putting conservation measures in place,” Paredes told Explorations Magazine. “Some of us had been conducting surveys in certain sites every year, but until this year we didn’t know the whole story of what was going on.”

The changes have occurred because of fishing. Traditional hook-and-line fisherman have been put out of business by vastly more damaging gill net fishing and “hookah” diving. Hookah fishermen use surface-supplied air through piping that allows them to walk along the seafloor for long periods of time. The technique is typically conducted at night when fish are resting, allowing the hookah fishermen to spear or grab large numbers of vulnerable fish and invertebrates.

In the most dramatic example of fishing impacts observed on the 2009 expedition a survey of San Esteban Island in the north revealed reefs devoid of fish and instead covered by mats of cyanobacteria.

There are areas which have flourished, though. One example is Cabo Pulmo near the southern tip of the Baja peninsula. Fishing restrictions there since 1995 have ensured that Cabo Pulmo retains a mix of sea life and flourishing fish populations. Other successes include Coronado Island inside the Loreto marine park and Los Islotes inside Espiritu Santo marine park.

Using compressed air has been banned in Mexico for sports fishermen for 40 years, but since commercial fishermen weren’t named specifically they had been allowed to use compressed air to clean the reef. In May 2009 this changed: the use of hookahs have now been outlawed for any type of fishing. Illegal fishing still goes on though, and environmental organisation Sea Watch is asking people to report any that they encounter at http://seawatch.org/en/Resource-Library/359/report-illegal-fishing

Further Reading:
Scripps Institution of Oceanography