The world's corals and coral reef ecosystems are in crisis. In just a few decades, scientists warn, these “rainforests of the sea” and all their rich biodiversity could disappear completely. While corals face numerous dangers, the overarching threats of global warming and ocean acidification are the greatest, and they're accelerating the decline of corals around the world.

The year 2016 marked the warmest ocean annual average temperatures ever recorded, putting corals at risk and foreshadowing what we can expect as climate change continues. Unprecedented warm ocean waters from 2014 through 2017 caused the most widespread and damaging coral bleaching event in history, killing millions of corals from the Great Barrier Reef to the Hawaiian Islands. Urgent action is needed to save the world's coral reefs from extinction.

That's why the Center has expanded our efforts to conserve coral reefs. Our ongoing coral work began with defending elkhorn and staghorn corals, for which we earned federal protection in 2006. In 2009 we filed a scientific petition to protect the 83 most vulnerable corals within U.S. waters — the corals that can benefit most from U.S. protection — as threatened or endangered under the Endangered Species Act. Under pressure from the Center, the National Marine Fisheries Service released a status review of the 82 corals, finding that 56 of them are likely to go extinct before the end of the century primarily because of ocean warming, disease and ocean acidification. 

In 2014, 20 corals saw victory when — after the Center filed three notices of intent to sue the Fisheries Service if it continued to ignore our petition — the National Marine Fisheries Service declared them threatened. The Center is now seeking Endangered Species Act protection for the cauliflower coral, Pocillopora meandrina, in Hawaii, which has seen a 36 percent drop in coverage around the Hawaiian Islands in recent years..  

The protected corals in the Caribbean include Dendrogyra cylindrusOrbicella annularisOrbicella faveolataOrbicella franksi and Mycetophyllia ferox, and those in the Indo-Pacific include Acropora globicepsAcropora jacquelineaeAcropora lokaniAcropora pharaonisAcropora retusa, Acropora rudisAcropora speciosaAcropora tenella, Anacropora spinosaEuphyllia paradivisaIsopora crateriformisMontipora australiensis,Pavona diffluensPorites napopora and Seriatopora aculeate


The declines of the petitioned-for corals have been linked to numerous major threats, including destructive fishing practices, overharvest, disease, predation, pollution and physical damage from boats. But the greatest threat of all to coral reefs is carbon dioxide emissions from burning fossil fuels that leads to ocean warming and acidification. The world's leading coral biologist, Charles Veron, warns us that unless CO2 concentrations in the atmosphere are reduced to below 350 parts per million soon, coral reefs and reef-dependent marine life will be committed to a terminal and irreversible decline due to global warming and ocean acidification.

In recent years global warming has caused nearly every reef around the world to suffer declines. When corals are exposed to elevated ocean temperatures they are susceptible to bleaching — which means that they expel the colorful zooxanthellae algae they need to survive — and while some corals may survive a bleaching event, many will die. This risk is growing ever more dangerous because global warming increases the severity, length, and frequency of bleaching events.

The more CO2 we spew into the air, the greater the consequences of bleaching will be for coral reefs. Corals face another ominous threat from the oceans becoming more acidic as they absorb CO2 from the atmosphere, and this means that corals will have difficulty growing and building their skeletons as ocean waters become more corrosive. Thus corals that suffer from bleaching may never be able to rebuild their majestic reefs.

If corals are to survive, they need relief from each of these threats, and the strong protections of the Endangered Species Act will be a vital step toward the conservation of corals and coral reef ecosystems. 

The Center sought protection for all corals in U.S. waters for which population declines have been estimated at more than 30 percent in 30 years. These include eight corals species in Florida and the Caribbean, nine corals in Hawaii and 67 corals occurring in American territories of the Pacific.

Photo by joshbousel/Flickr