Marine zoning in the Pacific Ocean, in combination with other measures, could significantly improve numbers of heavily overfished bigeye tuna and improve local economies, a fish modelling study has found.
Scientists working at the University of Hawaii at Manoa (Honolulu, HI), the Secretariat of the Pacific Community (SPC, Noumea, New Caledonia) and Collecte Localisation Satellites (CLS, Toulouse, France), have found that a network of marine zones in the Pacific Ocean could be a more effective conservation measure than simply closing relatively small areas to some types of fishing. These marine zones, where different fishing activities are allowed in different areas, may have significant and widespread benefits for bigeye tuna numbers. Dr John Sibert of the University of Hawaii Joint Institute of Marine and Atmospheric Research is one of four scientists leading the study. After testing the effectiveness of a range of conservation measures with an ecosystem and fish population model, Dr Sibert says the team found that the most effective measures were to:
"We found that simply closing areas off to fishing doesn't work, because the boats just move their operations to neighbouring zones and fish even harder. It's going to need a combination of approaches," he says.
"The model will help people evaluate alternative policies to manage tropical tuna fisheries. Our predictions can help countries estimate how effective conservation measures might be, relative to any economic effects, and tailor measures to suit their goals. The advantage of this approach is that effects can be estimated locally, as well as for the stock as a whole."
Half the current bigeye tuna catch is by longline, which targets high-value tuna sold as fresh fish. These fish command a market premium and sell for over $10 per kilogram.
The other half is caught in purse-seine nets as incidental bycatch when aiming to catch skipjack tuna. These juvenile bigeye tuna are sold to the canning industry for $1.70 per kilogram.
Dr Sibert says the study calls for a complete economic valuation of the Western Central Pacific Ocean (WCPO) tuna fishery.
He says the most effective conservation measures are those "which protect fish throughout their lifetime."
Rebuilding the bigeye-tuna stock will take at least 15 years, and will be affected by any climate changes the ecosystems experience.
Sibert, J., I. Senina, P. Lehodey, and J. Hampton. 2012. Shifting from marine reserves to maritime zoning for conservation of Pacific bigeye tuna (Thunnus obesus). PNAS 109(44): 18221.
University of Hawaii ‑ SOEST:
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Some, like dolphins or chimps, are sophisticated communicators. But do they have their own languages? Its a question that misses the point
Grey and harbour seals in the North Sea weave in and out of offshore wind farms in search of fish, which gather around turbines
Researchers have created wheat that is resistant to a common disease, using advanced gene editing methods.
An archaeological dig uncovers new clues about life and death in America's early history
Ted Stanley is giving $650 million to the Broad Institute of MIT and Harvard to find and treat the genetic underpinnings of mental illnesses. His son has bipolar disorder.
As far as agricultural genome research goes, this may be the best thing since sliced bread - wheat bread, that is.
The discovery and culturing of bacteria that eat and excrete electrons means we may soon find out just how little electricity fundamental life requires
The spectacularly well-preserved prehistoric sea creature sported compound eyes, body armor and two spiky claws for grabbing prey
The Beagle's library of more than 400 books has been reconstructed and made freely available in digital form
When the gorilla Willie B. had to move to a tiny cage at the Atlanta Zoo for six months, the vet staff decided to put Thorazine in the Coca-Cola he drank in the morning. Willie responded to the drug as many institutionalized humans do: He shuffled back and forth across his cage with dulled eyes.