PRESERVES & NURSERIES: Coral reefs all around the world are dying, and coral reef experts issued an alarm based on their first-ever global study. Extinction threatens one-third of all coral reefs, but preservation is possible if we reduce greenhouse gas emissions, pollution and overfishing and set aside marine reserves.

More than 32% of the 700 species of coral are on the verge of extinction, according to a study presented at the International Coral Reef Symposium in Fort Lauderdale, Fla., and published in last week's issue of Science. Losing coral reefs means losing global biodiversity, not to mention devastating a way of life for more than 500 million impoverished, tropical fishermen who depend on the reefs to feed their families.

Humans Threaten Coral Reefs

Corals are tiny marine animals whose exoskeletons make up the great reefs, which take millions of years to form. They grow in tropical and subtropical waters just off shorelines. Coral reefs provide food and shelter to marine life, 25% of which depends on the reefs.

Coral's plight cannot be blamed on any one factor, but all the major causes of its calamity have the same source—humans:

• Overfishing—Destructive fishing practices, such as the use of explosives and bottom trawling, destroy coral reefs.
• Agricultural runoff—Chemicals from farming make their way down rivers and into coastal coral beds, poisoning the water.
• Tourism—Both building and dredging along coasts for resorts pollute ocean water. Careless divers and snorkelers damage coral.
• Global warming—Rising water temperatures disrupt the symbiotic relationship between coral and an algae that supplies critical nutrients, without which the coral turns white. As the water temperature warms, the coral discharge the needed algae. This "bleaching event" weakens coral and makes it vulnerable to disease. (Warming sea temperatures also harm fish.)
• Ocean Acidification—Carbon dioxide from greenhouse gas emissions acidifies the ocean water, making it inhospitable to coral (see sidebar).

Losing the reefs could be devastating not only to marine life, but to the people who rely on them.

"They [coral reefs] are important for food and important for other types of livelihoods," said Prof. Kent Carpenter of Old Dominion University in Virginia, who led the study. "So, if we lose the ecosystems, we lose not only the biodiversity, but we also lose the capability of people to obtain income and food from coral reefs." (Voice of America, 7/11/08)

Coral Survival Depends on Marine Reserves

Last week the National Oceanic and Atmospheric Administration released a report that said half of the coral reefs in U.S. territory are in "fair" or "poor" condition, including these:

• Guam
• Palau
• Puerto Rico
• U.S. Virgin Islands

But Carpenter and the 38 other marine biologists involved in the study say we can save many of the world's reefs. How?

• preserving reefs in marine reserves
• reducing greenhouse gas emissions
• restricting fishing until certain fish populations recover
• reducing ocean pollution

To work, however, Carpenter said we need to take the above steps now. Otherwise, we can expect the coral reefs to die completely in 40 years.

"If we do not do those things, then, at the current level of how things are going, we will probably lose our coral reefs by the middle of this century," Carpenter said. "So, 2050 is the date that many people are predicting that coral reefs will cease to exist." (Voice of America, 7/11/08)

Copyright © 2010 Informify

Question for Readers:

Do you think establishing more marine reserves and greater fishing restrictions will help save the world's coral reefs?