President Obama’s proposal in June to expand a marine sanctuary around seven U.S.-controlled islands and atolls in the central Pacific Ocean drew immediate praise from scientists and conservationists, but has since sparked opposition from representatives of the tuna industry, including fishermen in Hawaii who say it would threaten their livelihood.

The tuna fishermen oppose the plan because commercial fishing is prohibited in the Pacific Remote Islands Marine National Monument, which would increase from nearly 83,000 square miles to nearly 755,000 square miles (215,000 square kilometers to nearly 2 million square kilometers) under the plan Obama announced.

“No other country is restricting fishing in its own waters to this extent, says Kitty Simonds, executive director of the Western Pacific Regional Fishery Management Council, which manages fisheries in the Pacific.

But conservationists argue that the proposed expansion would have minimal impact on the industry, saying fishermen haul little tuna from those areas.

“Even if those places are made off-limits, the fishermen won’t lose that percent of their catch because they will be able to fish in other areas, says Jack Kittinger, the director of Conservation International’s Hawaii office.

Although the public comment period ended August 15, Obama administration officials have met over the past few weeks with conservationists and fishing representatives to work out the details of what would be the world’s largest protected natural area. A final ruling could come any day, although administration officials declined to discuss their decision process.

President George W. Bush first designated the monument in February 2009, protecting an area that extended out to 50 nautical miles around seven uninhabited islands and atolls: Kingman Reef and Palmyra Atoll in the northern Line Islands, Wake Island, Jarvis Island, Johnston Atoll, Howland Island, and Baker Island.

On June 17, Obama proposed extending the monument to include the entire 200-nautical-mile U.S. exclusive economic zone around those areas.

“I’m using my authority as president to protect some of our nation’s most pristine marine monuments, just like we do on land,” Obama had said at the time.

National Geographic Explorer-in-Residence Enric Sala led a National Geographic science expedition to the region in 2005, which documented rich biodiversity and reefs in a largely pristine state. He says the proposed monument would protect deep corals that are thousands of years old, 22 species of marine mammals, five species of endangered sea turtles, and millions of fish and nesting seabirds. The area hosts one of the largest populations of manta rays and sharks that Sala has seen anywhere, including endangered silky and oceanic whitetip sharks. One of the islands, Kingman Reef, was featured in the July 2008 issue of National Geographic magazine.

The discoveries were cited by Bush in his presidential proclamation that created the monument. Bush, like Obama, used his power under the 1906 Antiquities Act to protect the area.

More than 135,000 U.S. citizens have sent letters of support for the proposed expansion, as have more than one million people from around the world, according to environmental organizations that tracked the submissions. More than 200 scientists who have worked in the region signed a letter of support, as have more than 40 national environmental groups and foundations, 30 Hawaii-based nonprofits, and 35 Hawaii-based businesses, including water sports outfitters.

In a September 12 letter to Obama, Maui County Mayor Alan Arawaka, who lived on Wake Island for two years as a child, wrote that as a diver, he has been distressed by the “severe decline in the coral reef habitats in Maui County and throughout Hawaii. To ensure “the survival and abundance of many species that may be threatened elsewhere, he added, it is “vitally important that we extend protection of these locales that have been minimally impacted by human presence.

The Obama administration declined to release information about the comments filed in response to the proposal, making it impossible to tell how much support opponents were able to generate during the comment period.

But American Samoa’s representative to Congress, Eni Faleomavaega, wrote a letter to the president in July opposing the expansion, saying it would have little impact on marine conservation and “prove an economic hardship for area fishermen.

Opposition From a Fishing Group

The Western Pacific Regional Fishery Management Council, based in Hawaii, had opposed the creation of the monument in 2009. At a boisterous town hall meeting in Honolulu in August and in a meeting at the White House on September 9, representatives of the council made their case against expansion, arguing that current fisheries laws adequately protect marine wildlife.

Simonds says the Hawaii-based longline fleet, which fishes for tuna and other large predatory fish, in 2000 set about 16 percent of its hooks in the area of the proposed monument expansion, marking the high point for fishing there.

That fishery is already a “global model of sustainability, she says, although she notes that it could be improved. She’d like to see purse seine fishermen switched from vessel day-limits to a catch quota system, which currently governs longline fishermen and is a better way to control overfishing, she says.

But Conservation International’s Kittinger says data from the Western and Central Pacific Fisheries Commission (which oversees international fishery agreements in the area) shows that, since 2008, less than four percent of the U.S. Pacific tuna catch came from within national waters, with just a fraction of that from within the proposed monument.

Simonds and her colleagues dispute that assessment. Sean Martin, who owns six commercial fishing boats and serves as president of the Hawaii Longline Association, says he and his colleagues frequently travel to the monument area, even though it is about 900 miles (1,450 kilometers) from Hawaii to the nearest of the seven islands.

Paul Dalzell, a senior scientist with the Western Pacific council, said, “Fishermen go where the fish are. Right now they’re in the eastern Pacific. But he noted that they often move with the ocean’s periodic temperature shifts.

During El Niño years fish tend to migrate toward the proposed monument expansion area, and the frequency of El Niños is expected to double due to climate change, says Dalzell.

Kittinger counters that, even during El Niño years, only 10 percent of the Pacific fleet’s total catch comes from that region. But Dalzell says during the 1997 El Niño, 21 percent of the catch of Hawaii-based purse seine fishermen was taken from the monument area.

Martin, who has worked as a fisherman for about 40 years, told National Geographic that the Hawaii-based fleet is getting squeezed by increasing limits on the high seas and in the waters of other countries, as well as substantially higher usage fees to fish within the waters of other countries.

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