No-fishing zones successfully restoring tuna while boosting fishing industry

Via SWNS

No-fishing zones are successfully restoring tuna while boosting the fishing industry, according to new research.

It is well-known no-fishing zones can help sedentary marine life such as coral or lobster.

Now scientists at University of Hawaii at Manoa have shown for the first time that they are also helping migrating fish traveling long distances.

Previously it was assumed no marine protected area (MPA) could be large enough to protect species that travel long distances, such as tuna.

But Papahānaumokuākea Marine National Monument is almost four times the size of California, and the world's largest no-fishing zone.

Scientists aboard fishing boats nearby but outside the area observed 54 percent more yellowfin tuna were caught, 12 percent more bigeye tuna and the catch rate for all other species increased by eight percent.

There are huge economic benefits to the zones too - globally the tuna fishing industry generates £35.5 ($39.9) billion a year and supports millions of jobs across the world.

Co-author Professor John Lynham at the Department of Economics at the University of Hawaii at Mānoa’s College of Social Sciences said: “We show for the first time that a no-fishing zone can lead to the recovery and spillover of a migratory species like bigeye tuna.”

Writing in Science, the team put the positive results down to tuna actually being homebodies, mostly living their lives in the same place.

Co-author professor Jennifer Raynor, at the Department of Forest and Wildlife Ecology at the University of Wisconsin-Madison, said tunas do not travel very far from their homes.

“Over the past 30 years, we have learned that tunas do not venture as far away from home as we once thought," she said.

“The Hawaiian Islands are a nursery for baby yellowfin tuna, and it turns out that many of these fish stay in the region.”

The zones have a cultural impact too because yellowfin tuna and bigeye tuna, otherwise known as ‘ahi, have historically been central to Hawaii’s culture and diet.

Dr. Sarah Medoff, another co-author and researcher at the School of Ocean and Earth Science and Technology at the University of Hawaii at Mānoa said: “Being born and raised in Hawaii, I know how important ʻahi is to the community here.

“It’s not just something eaten in fancy sushi restaurants, it’s the focal point of family gatherings, weddings, birthdays, graduation ceremonies and New Year’s Eve parties.

"It’s reassuring to know that the monument is protecting this resource for my own children and for future generations.”

Papahānaumokuākea was not created to generate benefits to the local tuna fishery when it was created in 2006 and expanded in 2016 - it was always intended to protect more biological and cultural resources.

The area is sacred to Native Hawaiians who co-manage the monument alongside the state of Hawaii and the federal government.

Professor Kekuewa Kikiloi from the Kamakakūokalani Center for Hawaiian Studies at the University of Hawaii at Mānoa, who was not involved in the study, said the research demonstrates just how important the protected areas in the Pacific are.

“This research by Medoff et al. reaffirms the value of large scale marine protected areas in the Pacific," he said.

“The protections that were fought for by Native Hawaiians and other stakeholders for Papahānaumokuākea serve to benefit everyone, including fishing interests.”