Scientists deliver plan for rescuing America's coral reefs
An international team of marine ecologists is urging the United States to take immediate action to save its fragile coral reefs. Their message is contained in a strongly worded essay titled "Are U.S. Coral Reefs on the Slippery Slope to Slime?" that appears in the March 18 edition of the journal Science.
"We're frustrated with how slowly things are moving with coral reef conservation in the United States," said Fiorenza Micheli, an assistant professor of biological sciences at Stanford University's Hopkins Marine Station. "Tiny steps are being taken, but they really don't address the overall problem."
Micheli and Stanford graduate student Carrie Kappel are among 11 researchers from the United States and Australia who co-authored the Science essay, which focuses on America's two major coral reef systems in Hawaii and Florida.
Florida's coral reef barrier stretches some 200 miles along the Florida Keys and plays an important role in the state's economy. "Annual revenues from reef tourism are $1.6 billion, but the economic future of the Keys is gloomy owing to accelerating ecological degradation," the authors note. "Florida's reefs are well over halfway toward ecological extinction. … Large predatory fishes continue to decrease, reefs are increasingly dominated by seaweed and alarming diseases have emerged."
In 1990, the U.S. government established the Florida Keys National Marine Sanctuary to protect the reef—the third longest in the world behind Australia and Belize. But pollution, overfishing, disease and thermal stress caused by climate change remain significant problems throughout the sanctuary, according to the authors. "Conversion of 16,000 cesspools to centralized sewage treatment and control of other land-based pollution have only just begun," they noted, and only 6 percent of sanctuary waters have been set aside as "no take zones" where fishing is prohibited.
In contrast, the neighboring countries of Cuba and the Bahamas have agreed to conserve 20 percent of their coral reef ecosystems, while Australia recently zoned one-third of its massive Great Barrier Reef as "no take" in an attempt to reverse further ecological decline.
The coral reefs of Hawaii's main islands—Oahu, Maui, Kauai and Hawaii—also show degradation similar to that of the Florida Keys, according to the authors. And while reefs in the isolated northwest Hawaiian Islands remain in relatively good condition, they, too, are showing signs of decline: "Monk seals and green turtles are endangered; large amounts of marine debris are accumulating, which injure or kill corals, seabirds, mammals, turtles and fishes; and levels of contaminants, including lead and PCBs, are high."
To prevent further ecological deterioration, the research team recommended that the United States start managing its coral reefs as whole ecosystems instead of as fragmented habitats. "For too long, single actions such as making a plan, reducing fishing or pollution, or conserving a part of the system were viewed as goals," they write. "But only combined actions addressing all of these threats will achieve the ultimate goal of reversing the trajectory of decline. We need to act now to curtail processes adversely affecting reefs."
Stopping overfishing will require integrated systems of "no take" areas as well as quotas on harvests, they say, and "terrestrial runoff of nutrients, sediments and toxins must be greatly reduced by wiser land use and coastal development." In addition, "slowing or reducing global warming trends is essential for the long-term health of all tropical coral reefs."
Like any other successful business, managing coral reefs requires investment in infrastructure, according to the authors. However, such investment will produce long-term benefits for the economy and the environment.
"Short-lived species, like lobster, conch and aquarium fish will recover and generate income in just a few years," they note. "Longer-lived species will recover, water quality will improve and the ecosystem will be more resilient to unforeseen future threats. Ultimately, we will have increased tourism and the possibility of renewed sustainable extraction of abundant megafauna. One day, reefs of the United States could be the pride of the nation."
The Science essay was co-written by lead author John Pandolfi of the University of Queensland, Australia; Jeremy Jackson, Scripps Institution of Oceanography and the Smithsonian Tropical Research Institute (STRI), Panama; Nancy Baron, National Center for Ecological Analysis and Synthesis; Roger Bradbury, Australian National University; Héctor Guzman, STRI; Terry Hughes, James Cook University, Australia; John Ogden, Florida Institute of Oceanography; Hugh Possingham, University of Queensland; and Enric Sala , Scripps.