U.S. coral reef ecosystems have declined in recent years and about half are considered to be in "poor" or "fair" condition due to threats ranging from global warming to overfishing, the federal government said in a new report Monday.
"While the report indicates reefs in general are healthier in the Pacific than the Atlantic, even remote reefs are subject to threats stemming from climate change, as well as illegal fishing and marine debris," Tim Keeney, co-chair of the U.S. Coral Reef Task Force, said in a statement issued with the report.
In the Caribbean, the report stated, "overall trends indicate that resource condition is declining and threats are increasing."
A quarter of all marine species need coral reefs to live and grow, while 40 percent of the fish caught commercially use reefs to breed, Keeney said in raising a call to action. "If we lose the reefs, you lose a very significant and important habitat."
Keeney noted that since the previous federal reef report in 2005, the Caribbean has lost at least 50 percent of its corals.
The report found that coral bleaching caused largely by rising sea temperatures is a major factor. Carbon dioxide released by burning fossil fuels is absorbed by the oceans, making the waters more acidic and corrosive on corals.
Land-based pollution, such as sewage, beach erosion, coastal development and overfishing also are to blame.
“There’s no question that ... man-made actions are the major cause for these losses and stresses on the reefs,” Keeney said.
Fewer fish in the sea
The deterioration is impacting reef fish as well as the coral themselves.
"Populations of harvested reef fishes in Florida and the U.S. Caribbean are largely depleted," the report stated, noting that only three percent of snappers and groupers observed between 2001 and 2007 were large enough to fish.
In Florida's Broward County, only 2 of the 242 groupers seen during four years of surveys were larger than the minimum legal size.
In the Florida Keys, 25 species of snapper and grouper were considered "overfished," the report noted.
At the same time, the number of recreational fishing vessels grew by 41,000 and 25 percent more saltwater fishing licenses were issued.
Dave Allison, a senior campaign director for the advocacy group Oceana, said the entire world’s coral reefs “border on disaster.”
“All the world’s coral reefs are being stressed by both short-term and long-term human impacts,” Allison said. “We’ve known about the human impact on corals for decades. It’s just that the combination of problems confronting the corals have never come together in such a perfect storm.”
10 threats cited
Released at the 11th International Coral Reef Symposium in Fort Lauderdale, Fla., the report cited 10 main threats to U.S. reef systems: climate change and coral bleaching; coral disease; tropical storms; coastal development; tourism and recreation; commercial fishing; subsistence and recreational fishing; vessel damage; marine debris; and nonnative species.
Most of the areas surveyed saw at least nine of those threats worsen in recent years, the report stated.
The report's authors noted that since the last status report, two coral species — Elkhorn and Staghorn corals — had become the first corals ever listed as threatened under the Endangered Species Act.
Keeney called coral “a sentinel species of the planet and "a major indicator of something that could go wrong with the environment."
Beyond their importance as breeding grounds for fish, reefs could also hold cures for diseases, he said.
The full report is online at ccma.nos.noaa.gov/stateofthereefs.