Bigeye tuna specimens. (Photo: Stock File)
MARSHALL ISLANDSWednesday, August 20, 2014, 23:40 (GMT + 9)
Newly released stock assessment that shows bigeye tuna is being overfished underlines why the Western and Central Pacific Fisheries Commission (WCPFC) must take decisive action at its December annual meeting to reduce further reductions in bigeye mortality.
“PNA said that measures adopted last year by the WCPFC to protect bigeye were inadequate, and the results of the detailed stock assessment support this conclusion,” said Dr. Transform Aqorau, CEO of the Parties to the Nauru Agreement (PNA), a bloc of eight nations that control waters where over 50 per cent of the world’s supply of skipjack tuna is caught. “Last year’s annual meeting did not do enough to stop overfishing of bigeye tuna and we had always known that it would not be enough.”
Scientists based at the Secretariat of the Pacific Community (SPC) delivered a comprehensive stock assessment for bigeye, yellowfin, skipjack and albacore tuna during the WCPFC’s annual Scientific Committee meeting held earlier this month in Majuro. These reports show that stocks of bigeye have dropped below the WCPFC “limit reference point” of 20 per cent to just 16 per cent of the original biomass now present. For the first time, scientists stated clearly that bigeye is being overfished.
Yellowfin tuna stocks were pegged by scientists to be below 40 per cent of their original unfished population, while skipjack stocks were the healthiest at slightly over 50 per cent. Albacore is also a concern, with scientists reporting that “there is a notable risk of recent fishing effort levels reducing the adult biomass of south Pacific albacore below the Limit Reference Point (of 20 per cent) within the coming years.”
Aqorau cautions that conservation measures need to be stepped up by the WCPFC for all tuna species.
Aqorau said the WCPFC members, which include all the major fishing nations as well as Pacific island countries, have known for several years that bigeye was in danger of being overfished.
“Now the scientific evidence is on the table,” Aqorau. The eight-member PNA, he said, will be working with other countries to gain consensus on measures needed to significantly reduce bigeye catches that will be taken up by the WCPFC at its annual meeting in Auckland, New Zealand later this year.
“It is clear that fishing of bigeye tuna needs to be cut by about 40 per cent to return to sustainable levels,” Aqorau said.
But there is heavy pressure on western Pacific tuna stocks from record-setting catches over the past several years. A record 2.65 million tons of tuna was hauled from the western Pacific in 2012 valued at USD 7 billion, and last year’s catch was only marginally smaller.
“PNA has been a leader in enforcing conservation measures to ensure the tuna fishery remains sustainable in the long-term,” said Aqorau. “Since 2009, PNA has enforced moratoriums on the use of fish aggregation devices (FADs), closed two high seas pockets to fishing as a condition of in-zone licenses, and required 100 per cent observer coverage of all purse seiners and in-port transshipment of tuna by purse seiners.” These have all been essential elements for successful in-zone management of tuna resources.
"But these in-zone measures must be complemented with similarly clear requirements for fishing on the high seas, with a particular focus on reducing catches by longline fishing boats that target bigeye and yellowfin tunas for global sashimi markets," Aqorau said.
“FAD closures in PNA waters are protecting juvenile bigeye, but we have yet to see compatible measures by high seas longline fleets targeting mature bigeye,” Aqorau pointed out.
“Currently, PNA is shouldering the burden for bigeye conservation, but PNA waters are mainly a skipjack fishery,” he stressed. Tuna congregate under FADs, which are essentially platforms used to attract fish. Many FADs are outfitted with sophisticated sonar that tells fishing vessels the size of tuna schools under the FAD. Bigeye catches drop dramatically during the PNA FAD ban from July through October.
PNA currently bans use of FADs for tuna fishing four months of the year, but is prepared to increase this to six. “But we want to see the commitment from distant water fishing nations to address bigeye catch on the high seas and some consideration for PNA for losses PNA domestic vessels that fish only in-zone will sustain if the FAD ban is expanded,” Aqorau stressed.
Not only do distant water fishing nations need to take action to reduce catches on the high seas, they need to begin providing operational catch data required by their membership in the WCPFC. Aqorau praised the United States for complying with this requirement by changing its domestic legislation, and said four Asian nations that have yet to comply must do so.
“PNA is providing the Commission with all catch data from fishing within our waters. The Asian fishing nations need to do the same for their catches on the high seas. The lack of data leaves gaps in the stock assessments and undermines the sustainability of the fishery for everyone because we are forced to make decisions based on incomplete information,” he concluded.
Related articles:
-Data gaps affect pacific tuna assessment
- Greenpeace demands urgent recovery plan for bigeye tuna