Martin Pratt, an expert on maritime boundaries at Durham University in England, says that the only environmental protection afforded under the United Nations Convention on the Law of the Sea relates to so-called Exclusive Economic Zones (EEZ) in waters within a territory extending 200 nautical miles (370 kilometers) from a country's coastline. "In Antarctica," he says, "there's this problem where states have claims, but those claims are frozen and the question is whether establishing an EEZ represents a violation of the treaty."

The current debate about the treaty's stability began in October 2007 when the U.K. announced that it would file a claim under the Law of the Sea extending the seabed boundaries of their Antarctic territory based on the extent of the continental shelf. The British claim already overlaps with Argentina and Chile, heightening the potential for a territorial dispute.

Argentineans are still fuming over their defeat in 1982 when they tried to reclaim South Georgia Island and the Falkland Islands from the U.K.—the closest thing we've had to an Antarctic war. Although Britain insists it will not contravene restrictions against oil, gas and mineral exploration in Antarctica, Robin Churchill, an expert in international law at the University of Dundee in England, says the move has the potential to be "quite destabilizing." That would be shame, he says, because "the Treaty has promoted scientific research by opening Antarctica up for any scientist to go anywhere, fostering a spirit of cooperation."

In February, Australia—with U.N. approval—expanded its seabed borders along the Kerguelen Plateau around Heard and McDonald islands, pushing into the Antarctic Treaty jurisdiction. Although Australia says that mineral and petroleum exploration is out of the question, some fear that this move could open the door to trawling on the seabed and bioprospecting in the region.

"Legally, it may be defensible," says Alan Hemmings, a specialist on Antarctic governance at the University of Canterbury in New Zealand. "Politically, it's more problematic."

Ironically, Australia's move may serve to strengthen rather than weaken environmental protection. Back in 2002, an Australian research boat sent a Japanese whaling vessel scurrying back to its mother ship after it was spotted inside Australia's EEZ near Prydz Bay. Last December, Australia sent the Ocean Viking to monitor Japan's whaling fleet in Antarctica and by late January, an Australian federal court had ruled that it was illegal for Japanese to whale within 200 nautical (230 statute) miles of their Antarctic territory. Pratt says it is still a "tricky legal problem" and "an issue [that will] presumably [be] tested in court somewhere, sometime."

Farther north, in the southern Indian Ocean, Australia runs regular patrols around Heard Island, France patrols the Kerguelen Islands, and South Africa has a marine-protected area around its Prince Edward Islands, which are right along the northern boundary of the treaty area. Ainley says that patrolling these sovereign territories—which partially overlap with the treaty regime—is the only enforcement of fishing regulations in the region.

The Antarctic Treaty has provided a model for conservation of the terrestrial environment, but biologists agree that the marine environment has suffered under Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR).

The Commission (created by the CCAMLR) provides licenses to vessels fishing in the Southern Ocean and requires licensed boats to have an observer on board to monitor catch levels. It also has the ability to set up marine protected areas in the Southern Ocean, such as one proposed for the Ross Sea. But it has yet to do so and, in general, adoption of fishing regulations proposed in the Commission's scientific working groups has moved at a glacial pace in the face of opposition from the powerful fishing industry.