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Lobed coral

Lobed coral

NOAA Flower Garden Banks National Marine Sanctuary

U.S. agency says 20 coral species are threatened

Ocean acidification, warming waters, and disease could lead 20 species of Caribbean and Pacific corals to be at risk for extinction by 2100. That argument formed the basis for a decision Wednesday by the National Oceanic and Atmospheric Administration (NOAA) to add them to the list of threatened corals under the Endangered Species Act (ESA).   

"I don’t think we can make any decision anymore about ESA listings without taking into account the reality that the planet is warming, that the ocean is changing, and will continue to change," said Russell Brainard, NOAA’s Coral Reef Ecosystem Division chief, in explaining the agency’s action. Two coral species are already listed as threatened, a less protective category than endangered. The agency must now decide how to reduce the stress of those changes on coral species, some of which have declined by 90%.            

In 2009, the Center for Biological Diversity (CBD) asked NOAA to list 83 species under the federal law, arguing that each one had declined by at least 30% in 30 years. In 2012, NOAA proposed listing 66 of those petitioned corals as threatened and moving the two species already on the list, the Caribbean elkhorn and staghorn corals (Acropora palmata and Acropora cervicornis), to the most protective category of endangered. David Bernhart, the protected resources chief for NOAA Fisheries' Southeast region, told reporters yesterday that new information about the abundance of each coral species, their location, and how they respond to threats like pollution and ocean warming led to fewer listings than had been anticipated.

While protecting five Caribbean and 15 Indo-Pacific corals marks an important acknowledgement that corals are in trouble,” said CBD’s Miyoko Sakashita, it falls short of what the environmental group had wanted. “There is a little bit of a mixed reaction because there were some corals that we felt deserved protection that didn’t ultimately get it.” According to Melanie Rowland, a retired NOAA attorney and ESA expert not involved in the listing decision, it’s not unusual for an agency to change its mind between its initial proposal and its final decision, especially when there is new research.

Now that 20 corals are listed, the question is how to arrest their decline. Threatened status does not automatically restrict activities like fishing or coastal development. However, other federal agencies undertaking projects that could harm corals, such as building ports, must now consult with NOAA first. “Those bigger threats [from] climate change have bigger impacts and harder solutions,” said Mike Tosatto, NOAA’s fisheries administrator for the Pacific Islands. “Land-based impacts of fishing and land-based pollution are generally lesser threats overall, but [they are] something that we might be able to more effectively address.”

The agency already has a coral reef conservation program, and it will continue to study climate change impacts to corals while trying to reduce overfishing of reef ecosystems and reduce polluting runoff from land that can cause coral disease. But many scientists fear those steps, by themselves, won’t be enough to save corals. “Without reducing carbon dioxide concentrations in the atmosphere, no amount of good management of these ecosystems is going to save coral reefs,” said Katharine Ricke, a climate scientist at the Carnegie Institution for Science in Palo Alto, California, who has modeled large-scale climate impacts to corals. 

*Clarification, 10 September, 2:35 p.m.: David Bernhart's NOAA position has been clarified.