Last week's dumping of four unarmed bombs into Australia's Great Barrier Reef by two American fighter jets during a training exercise gone awry is just the latest insult to a delicate ecosystem already under siege from a variety of man-made threats, environmentalists say.
The incident occurred on July 16, when two AV-8B Harrier aircraft launched from the U.S.S. Bonhomme Richard ran out of fuel and were each forced to jettison an inert practice bomb and an unarmed laser-guided bomb, none of which exploded.
The emergency dump site was a channel about 164 feet (50 meters) deep, located approximately 18 miles (30 kilometers) south of Bell Cay in the Great Barrier Reef Marine Park, according to a statement issued by the U.S. Navy.
Despite assurances by the Navy that the site was selected to "minimize the possibility of reef damage," environmental groups are calling for the ordnance to be removed as soon as possible and for the incident to be investigated.
"We need to know why it happened," said World Wildlife Fund-Australia's Richard Leck. "There's an enormous amount of threats around the reef ... and having more threats occur in this form is certainly the last thing the reef needs."
The bomb drops happened on the second day of Talisman Saber, a biennial military joint training exercise between Australia and the U.S.
Felicity Wishart of the Australian Marine Conservation Society (AMCS) said she would like to see an end to such exercises near the reef. "It's not just the bombs. It's all the ship movement and aircraft noise," she said. "All of these things are not a normal part of that particular environment."
The dumping of the bombs has sparked public outrage. Australian Senator Larissa Waters called the drops "outrageous."
"Have we gone completely mad?" Waters told the Australian Broadcasting Corp. "Is this how we look after our World Heritage area now? Letting a foreign power drop bombs on it?"
Reactions on Twitter ranged from disbelief to sarcasm. "Say whaaaaat?! Nemo is rightfully pissed," tweeted @VIPVirtualSols. @BrockMaria wrote: "Seriously—like seriously?"
The U.S. Navy says it is currently reviewing the possibility of retrieving the bombs. "If the park service and the government agencies of Australia determine that they want those recovered, then we will coordinate with them on that recovery process," U.S. 7th Fleet spokesman Lt. David Levy told the Seattle Times on Monday.
Insult to Injury
The military mishap is merely the latest threat to the reef, which stretches for some 1,250 miles (2,000 kilometers) off northeast Australia's Queensland coast.
The reef is the largest structure on Earth built by living organisms. It is home to a staggering diversity of marine life, from mollusks and fish to sea turtles and aquatic plants.
But in recent years, the reef has not only been battered by global challenges such as climate change—which has been blamed for an increase in severe category 4 and 5 cyclones—but also by local problems. The most serious of these are farm runoff and industrial development, conservationists say.
As a result of poor land management, 17 million tons of agricultural runoff—most of which is from human activities, as well as fertilizers and pesticides—flow into the reef from rivers each year, AMCS's Wishart said.
The nutrient runoff has been blamed for outbreaks of thorn-crowned starfish, a species that can eat its weight in coral everyday and that has decimated large parts of the reef.
There is also growing alarm over plans to expand or construct so-called "megaports" that requires dredging the seafloor and dumping the unearthed soil back into the reef's waters.
"We think the dumping of industrial waste into the Great Barrier Reef is a practice that doesn't belong in this day and age," Leck said.
All of these pressures are negatively impacting the coral organisms that create and maintain the reef, scientists say. A government-funded study published last year in the journal PNAS concluded that the reef has lost half of its hard coral cover during the past 27 years.
'List of Shame'
Concerned by the rapid pace of the reef's deterioration, the World Heritage Committee of the United Nations Educational, Scientific, and Cultural Organization (UNESCO) recently warned that without the urgent implementation of sustainable management improvements, the reef could land on its list of World Heritage in Danger as early as 2014.
The group made a series of recommendations, and officially requested that Australia revamp plans to manage the reef.
"There's a lot the Australian government needs to do before the deadline of June next year to make sure the reef isn't put on that 'list of shame,'" WWF-Australia's Leck said.
But even if Australia manages to change farming practices and control industrial development to reduce pressure on the reef, it won't be able to address the greatest danger to the reef by itself, scientists say.
"The most significant long term threat is climate change," said Hugh Sweatman, a behavioral ecologist at the Australian Institute of Marine Science.
Solving that "requires a global solution to reduce carbon emissions sharply," Sweatman said, "but that continues to elude humanity."
Brian Handwerk contributed reporting to this article.
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