Hawaii reefs doing well but are still in hot water

Humans pose main trouble for isles’ coral, report says

Coral reefs near Hawaii are in better shape than reefs in other parts of the United States, particularly those in the Caribbean Ocean ravished by rising ocean temperatures, the National Oceanic and Atmospheric Administration said yesterday.

But reefs in heavily populated areas, such as Oahu, commonly suffer more degradation than reefs around some of the other islands, state officials said.

FULL STORY »

Despite bleak news of poor coral reef ecosystems in U.S. states and territories released in a federal report yesterday, coral reefs around the main Hawaiian islands are good, on average, and good to excellent in the Northwestern Hawaiian Islands.

Almost half the coral reef ecosystems in U.S. territory are in poor or fair condition, mostly because of rising ocean temperatures, according to the National Oceanic and Atmospheric Administration report.

The reefs discussed in the report serve as breeding grounds for many of the world's seafood species and act as indicators of overall ocean health.

"They are a major indicator of something that could go wrong with the environment," said Timothy Keeney, NOAA's deputy assistant secretary for oceans and atmosphere.

But Hawaii has not seen the kind of massive mortality caused by cells of hot water sitting for weeks over corals such as in the Caribbean, said Athline Clark, who helped prepare the report and is state superintendent for Papahanaumokuakea Marine National Monument in the Northwestern Hawaiian Islands.

The Northwestern Hawaiian Islands reefs are isolated and pristine, while those around the main Hawaiian islands are generally and on average in good condition, but are in fair or poor conditions in other areas, she said.

Waters off heavily populated areas, such as Oahu, commonly suffer more reef degradation than waters around some of the other islands, said Clark, who works for the state Department of Land and Natural Resources.

Clark cited isolated incidents of higher ocean temperatures in the northern part of the Northwestern Hawaiian Islands in 2002 and 2004, and the main Hawaiian islands in the 1990s, though not to the degree that they have occurred in the Caribbean.

While those can be attributed to global warming, most of the problems affecting Hawaii's reefs are more from human use and not major climatic shifts, Clark said, though he acknowledged that "at the end of the day, it's all about us."

Reefs around the main Hawaiian islands are subject to a number of impacts such as altering the shoreline, water pollution, alien species such as algae, losing critical nursery habitat, and high-pressure fishing including recreational fishing, Clark said.

The decline in near-shore reef fish around the main Hawaiian islands can be attributed to these types of human activity, not climate change, Clark said.

Also, "upland development where sediment comes down and smothers reefs" is a major concern, especially on Kauai, she said. Other problems came from the Ka Loko Dam breach and heavy rain that washes sediment onto the reefs and leaves them covered in mud and trees, she said.

"If we lose the reefs, you lose a very significant and important habitat," Keeney said.

Since NOAA's last report in 2005, the Caribbean region has lost at least 50 percent of its corals, largely because sea temperatures have risen, Keeney said.

The 569-page report took 18 months to complete with input from 270 federal, state and university scientists. It documented 15 ecosystems in U.S. states and territories, including the U.S. Virgin Islands, Puerto Rico, Florida, Hawaii, American Samoa and Guam. It was released at the 11th International Coral Reef Symposium in Fort Lauderdale, Fla.

"We can actually document these declines now," said Jenny Waddell, co-editor of the study and an NOAA marine biologist.

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.

The study does not make recommendations, but simply serves as what its authors deem a "call to action" for state governments and Caribbean countries.

Keeney sees corals as "a sentinel species of the planet" and calls them "the rain forests of the sea." Beyond their importance as breeding grounds for fish, reefs could hold cures for diseases.