Tackling the over-fishing crisis – no take zones

cabo pulmo (credit: jeff gunn)

New research has again shown that no take zones in the seas and oceans can be a major way in which to make fishing sustainable in the oceans and seas. The new research covered an area of ocean off Baja California. This marine park and no take zone has seen fish numbers increase by over 460% in 10 years.

The Cabo Pulmo National Park was established by the Mexican government in 1995 after the area had effectively been laid barren by overfishing. Local officials and citizens have been fully supportive of enforcing a strict no take zone in the marine reserve.

Cabo Pulmo reef recover exceeds expectations.

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

This latest marine wildlife study has been published in the online journal Public Library of Science (PLoS) ONE.

During some seasons thousands of mobula rays congregate inside the park and swim above the reef in a magnificent way.

“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.”

Just 10 years to return to a near pristine marine ecosystem.

One of the most positive discoveries of this on-going 10 year old study is the speed at which the marine environment can recover if managed correctly. Cabo Pulmo National Park now has a wealth of species and complexity of interaction that is only seen in remote ecosystem that have not previously been commercially fished.

“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.”

Exequiel Ezcurra, Director of the University of California Institute for Mexico and the United States (UC MEXUS) and co-author of the article remarked,”I participated, back in the 1990s, in the studies for the declaration of the marine park. Frankly, we decided to go ahead because the community was so determined but the place at that time was not in good environmental health. If you visit the place now, you cannot believe the change that has taken place. And all of it has occurred thanks to the determination of a community of coastal villagers that decided to take care of their place and to be at the helm of their own destiny.”

Introduction of no take zones boosts local economy.

As the big fish and top predators returned so the local community has benefited financially. The re-established reef communities have led to a boom in eco-tourism with diving companies and sea kayaking activities attracting tourists from around the world to the area. But this has also had a negative impact with major resort developers now looking at exploiting the area. The new development could destroy the very reefs within a couple of years that is making the area so attractive.

“Few policymakers around the world are aware that fish size and abundance can increase inside marine reserves to extraordinary levels within a decade after protection is established; fewer still know that these increases often translate into economic benefits for coastal communities” said Aburto-Oropeza. “Therefore, showing what’s happened in Cabo Pulmo will contribute to ongoing conservation efforts in the marine environment and recovery of local coastal economies.”

No take zones can be important fisheries management tool.

This is yet further evidence that well managed and enforced no take zones can lead to a recovery of fish including commercial fish species. With European fisheries under pressure from over-fishing the EU and individual countries need to look to the value of setting aside at least 33% of territorial waters as no take zones. This will ensure that there are sufficient nursery grounds for juvenile fish to grow and mature before being harvested.

No take zones are not the ideal answer for some highly mobile species such as cod but they have been very effective in supporting other commercial marine species such as plaice, mackeral and lobster. If these very small no take zones were substantially increased then many more species will be helped and fishing could become sustainable as an industry.

There are many cases around the world where no take zones have been extremely effective and the success of this Cabo Pulmo National Park just highlights yet again how quickly marine environments can recover if the policy makers are prepared to take the bold steps needed.