Representatives of 25 governments met in Chile last month to discuss the formation of a South Pacific Regional Fisheries Management Organization and sustainable-fishing regulations for the region’s high seas.

Environmental groups lauded one of the principal outcomes of the meeting: the creation of rules that would effectively end a fishing method called bottom trawling in the South Pacific’s international waters.

“Bottom trawling is the world’s most destructive fishing practice, and it’s being done throughout the high seas, the least protected place on earth,” says Matthew Gianni of the Deep Sea Conservation Coalition, a global network of marine-conservation organizations. “This meeting was a major step forward in the conservation of high seas fisheries.”

But industrial fishing operators, while supportive of restrictions on bottom trawling, complained that the rules go too far. Meanwhile, green activists and some fishing-industry representatives were concerned that a second measure adopted—a two-year limit on fishing for jack mackerel (Trachurus murphy)—is structured in such a way that the species will come under more pressure rather than less.

Eighty percent of Chilean fishing in the region’s high seas is aimed at jack mackerel, which is used mainly to make fishmeal and is considered by the United Nations Food and Agriculture Organization to be in a state of “overexploitation.”

The provisional limit, intended as an interim measure while a final agreement is negotiated, would limit the jack mackerel catch to its levels prior to Jan. 1, 2008, when the measure is slated to take effect. Héctor Bacigalupo, general manager of Chile’s National Fishing Association (Sonapesca), asserts that this creates a “perverse incentive” for vessel operators not currently fishing for jack mackerel to begin doing so between now and Jan. 1.

Bacigalupo says that while his association backs rules on bottom trawling, the agreement reached in Chile went too far. “The proposal approved at this meeting as an interim measure on bottom fishing has exceeded recommendations by the United Nations and will in reality mean a moratorium for the next two years, making our region the only one with such a limitation,” he says.

The high seas, located 200 miles off of sovereign coastlines, make up about two-thirds of the world’s oceans. The South Pacific, which makes up about one-fourth of the world’s oceans, extends roughly north to south from Ecuador and the equator to Antarctica and east to west from Chile to Australia.

Fishing on the high seas has not been regulated by international agreement, and has until recently escaped the control of governments. Meantime, as near-shore waters are increasingly overexploited, fishing fleets have moved into the deeper international waters, in many cases using fishing methods that are banned or restricted within the sovereign zone.

By far the greatest cause of damage to marine life in the high seas has been bottom trawling, which involves dragging heavy nets and rollers across the sea floor. Bottom trawling, responsible for about 80% of the high-seas catch of bottom species, is likened by marine conservationists to strip mining. It utterly destroys fragile coral reefs (half of the planet’s coral reefs are found in high-seas areas) and obliterates nearly all marine life in its path. Worse, scientists say 98% of the ocean’s species live on or just above the sea floor.

Overall, scientists warn that bottom trawling forever destroys countless thousands of endemic species and species that have yet to be discovered. New species often are found on sea mounts, essentially underwater mountains. There are an estimated 100,000 sea mounts globally but scientists so far have only studied about 400.

In Chile last month, the participating governments, which included the United States, the European Union, Japan, China and other major fishing interests, agreed on bottom trawling measures based on a landmark resolution adopted by the UN General Assembly in December 2006.

That resolution prohibits bottom trawling from high seas areas where ecosystems are considered vulnerable unless an acceptable environmental impact assessment is prepared. The assessment, to be reviewed by a scientific committee of the regional South Pacific fishing body, would have to demonstrate that precautionary measures could be implemented that would prevent damage to such ecosystems.

The bottom-trawling measure takes effect on September 30. It also calls for onboard observers for all types of bottom fishing in the high seas, and mandates vessels must not fish within five nautical miles of vulnerable ecosystems such as coral reefs.

Juan Carlos Cárdenas, executive director of the Chilean marine protection group Ecoceanos, says environmental organizations are optimistic that bottom trawling may be halted not only in the South Pacific, but worldwide thanks to the agreement reached in Chile.

“Because all the big fishing nations were party to this agreement, and they agreed to implement the UN recommendations, we believe that this sets an important global precedent,” Cárdenas says.

Environmental groups share the concern of Chilean fishing industry executives that the Jan. 1 start date of jack-mackerel limits could precipitate a destructive influx of new jack-mackerel fishing operators in the interim. However, they feel that even if the jack mackerel catch were limited to its current level, this would be insufficient. Absolute reductions are in order, they argue. “If mackerel stocks are allowed to be overfished, the ecological, social and economic impacts would be serious, especially for dependent local communities and for species such as tuna and swordfish that feed upon mackerel,” Alistair Graham, high seas policy advisor to the World Wide Fund for Nature, said in a press statement.