Survey Finds Corals Are Among the Most Imperiled Species on Earth

More than a quarter of the world’s reef-building corals are threatened with extinction, says a new survey in Science. That makes corals the world’s most endangered group of animal species, along with frogs and toads. Climate change and human activity are disrupting the reefs: The corals’ symbiotic relationships with algae are being disturbed by warming waters, and untreated sewage released into oceans is causing massive algal blooms that suffocate the tiny organisms. In 1998, a single reef destruction caused by warming seas killed an area half the size of the Amazon. In less than 50 years, one scientist who participated in the survey said, there could be no coral reefs left in some regions, including the Caribbean.