Human Activities Threaten Coral Reefs
09 August 2010
Scientist Scott Porter holds coral samples that he removed in June from an oil drilling rig in the Gulf of Mexico. He is studying the effects of the BP spill.
BOB DOUGHTY: This is SCIENCE IN THE NEWS in VOA Special English. I'm Bob Doughty.
FAITH LAPIDUS: And I'm Faith Lapidus. Today we tell about threats to coral reefs and some new discoveries about these ancient, biological structures.
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BOB DOUGHTY: Corals are groups of small organisms called polyps. Millions of polyps grow together to form coral reefs. America's National Oceanic and Atmospheric Administration, NOAA, says the coral reefs that exist today are up to fifty million years old. The ancestors of these reefs were formed at least two hundred forty million years ago.
However, human activities are threatening the world's coral reefs. NOAA scientists say the main threats are pollution, overfishing and climate change. As a result, coral reef populations are decreasing worldwide.
An undated image provided by NOAA shows a shallow-water coral reef in the Florida Keys
NOAA says an estimated twenty percent of the reefs have been damaged beyond recovery. About fifty percent of the remaining coral are under risk of collapse.
FAITH LAPIDUS: Now there is a new threat facing coral reefs in the Caribbean Sea. The threat comes from another sea creature.
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