A group of island nations meeting at a conference in Honolulu starting today says it wants the United States to significantly reduce its use of purse seine nets in the central and western Pacific in light of overfishing of bigeye tuna.

Members of the Western and Central Pacific Fisheries Commission, which includes 24 nations and the European Union, are meeting this week at the Marriott Ihilani Resort at Ko Olina.

They include the eight parties to the so-called Nauru Agreement, island nations that want the United States to reduce the number of days its boats fish each year.

While such a reduction is not on the conference agenda, the United States and Pacific island countries are negotiating an extension of the 1987 Multilateral Treaty, which allows the United States 40 vessels and no limit on fishing days. That treaty expires on 2013.

A purse seine is a large fishing net shaped like a fence with floats along the top and weights on the bottom. A vessel releases it into the ocean to encircle and capture schools of fish.

Most U.S.-flagged purse seine fishing vessels are based in American Samoa, where there was a tuna canning factory until August 2009, and some other western Pacific island countries. The American Samoa factory is expected to reopen next year.

Overfishing of bigeye tuna has had an effect on Hawaii’s fishing industry, including the imposition of quotas on longline fishing that have reduced bigeye fishing by 10 percent since 2004.

Hawaii’s longline fishing vessels virtually stopped bigeye fishing in the central and western Pacific as of Nov. 22 after reaching their quota, and are now fishing in nontraditional waters in the eastern Pacific, where the trips are longer and it is unknown how much tuna is there.

"We don’t know what the results are going to be," said Brooks Takenaka, assistant general manager of the fish auctioneer United Fishing Agency. "How that’s going to work out is anybody’s guess."

Greenpeace members plan to attend the conference and urge attendees "to do the right thing, follow the science, end the overfishing and rebuild the tuna fish populations to healthy levels," said Phil Kline, oceans campaigner for Greenpeace USA. "Do not repeat the mistakes of the rest of the world where their tuna fisheries are totally depleted."

Two Greenpeace members climbed to the top of Aloha Tower yesterday and hung a banner urging members of the commission not to "let time run out on tuna."

After more than an hour, the two climbers rappelled down with the banner and were questioned by Honolulu police, Kline said.

"We don’t know if they’re facing trespassing charges," he said, "but we wanted to send a message."

Today, Greenpeace officials plan to "work inside the meeting, talking to the delegations," Kline said.

The Western Pacific Regional Fishery Management Council, which acts as a policy adviser to the U.S. secretary of commerce, has been supporting the use of various methods to increase bigeye tuna numbers and prevent overfishing.

Paul Dalzell, a senior scientist with the council, said in order to increase the bigeye stock, there needs to be a reduction in the use of purse seine nets at fish-aggregating devices — open-ocean buoys — because too many juvenile bigeyes are being caught before they become sexually mature and can propagate.

The central and western Pacific provides about 54 percent of the world’s tuna, amounting to about 1.3 million tons annually.

The United States and Japan are the largest consumers of canned tuna.

James Movick, deputy director general of the Pacific Islands Forum Fisheries Agency, said while overfishing for bigeye tuna is not at a critical stage, there is overfishing, and his group’s goal is to reduce the bigeye catch by 20 percent to 30 percent.

At a conference in April, parties to the Nauru Agreement banned purse seine fishing by vessels under license to the group in some high seas around their nations as of Jan. 1. That agreement covers an estimated 25 percent of the world’s tuna catch.

The countries signing the agreement were the Federated States of Micronesia, Kiribati, the Republic of the Marshall Islands, Nauru, the Republic of Palau, Papua New Guinea, Solomon Islands and Tuvalu.

Commission members also include Australia, China, Canada, the Cook Islands, the European Union, Fiji, France, Japan, South Korea, New Zealand, Niue, the Philippines, Samoa, Chinese Taipei, Tonga, the United States and Vanuatu.