Climate Change Threatens These 5 Important Coral Reefs

Coral reefs are considered the “rainforests of the sea” because they host such a wide variety of animals and plants, produce so much food and provide so many essential services that make life on Earth possible.

They occupy only .2 percent of the ocean, notes the Earth Institute at Columbia University, yet are home to a quarter of all marine species. Crustaceans, reptiles, seaweeds, bacteria, fungi and over 4,000 species of fish live in and around coral reefs. With an annual global economic value of $375 billion, coral reefs provide food and resources for over 500 million people in 94 countries and territories.

Coral reefs not only help protect land, they help create it, too. They can reduce the force of giant waves generated by storms and tsunamis and populate the remnants of volcanic islands once the lava cools and sinks below the waves. Just as we have found medicines hiding in rainforest plants, we may find compounds to fight disease on coral reefs.

Plus, coral reefs are spectacular. If you ever have a chance to snorkel or dive around a reef, take it (though swim carefully to avoid any damage). You’ll be amazed at the beauty and wonder a coral reef inspires.

Given how essential coral reefs are, you’d think we’d be doing everything in our power to protect them.

Not so.

Overfishing robs them of the predators, prey and “service” creatures like parrotfish and urchins that clean large algae off corals. Development of coastal areas leads to dredging that pollutes water with sunlight-blocking sediment. Runoff full of agricultural chemicals and wastewater smothers corals. Invasive species transported in the bilge water of transoceanic vessels take their tolls as well.

A particularly serious threat is posed by climate change. Increasing levels of carbon dioxide in the atmosphere are causing the oceans to warm, making them more acidic, explains

“Warm water causes bleaching episodes in which coral polyps expel the microscopic algae that live inside their tissues and nourish them. Algae provide corals’ color, so the reefs turn white. Corals can recover, but the process stresses and may kill them. Acidification, which occurs as seawater absorbs CO2 from the atmosphere, reduces the amount of carbonate available for corals to build their skeletons, so reefs grow more slowly and become weaker.”

“The coral bleaching and disease, brought on by climate change and coupled with events like the current El Niño, are the largest and most pervasive threats to coral reefs around the world,” said Mark Eakin, NOAA’s Coral Reef Watch coordinator. “As a result, we are losing huge areas of coral across the U.S., as well as internationally. What really has us concerned is this event has been going on for more than a year and our preliminary model projections indicate it’s likely to last well into 2016.”

Perhaps because they are underwater and fundamentally defenseless, coral reefs are among the planet’s most endangered ecosystems.

Here’s a snapshot of five important coral reefs worldwide and the dangers they face.

Tropical Reef Grunt

Coral Necklace off Florida’s southern tip – Between Key Biscayne and Dry Tortugas, the Florida Keys contain about 6,000 coral reefs. This reef system—third largest in the world—contains more than 100 species of soft and stony corals and hundreds of fish species, from tiny sergeant majors to giant barracudas. In 1997, reports the National Wildlife Federation, federal researchers discovered that disease on Florida’s coral reefs had increased nearly threefold. The disease may be linked not only to the draining of the Everglades and tourism in the Keys, but to polluted runoff from farms, factories, cities and even our own lawns.

The Great Barrier Reef, Queensland, Australia

The Great Barrier Reef off Australia’s western coast – About 35 per cent of corals on this magnificent reef have been killed by bleaching. Scientists are drawing a direct link between climate change, rising ocean temperatures and the inability of coral to thrive when waters heat up as little as 1 degree Celsius above their normal average temperature.”This year is the third time in 18 years that the Great Barrier Reef has experienced mass bleaching due to global warming, and the current event is much more extreme than we’ve measured before,” said Professor Terry Hughes of the ARC Centre of Excellence for Coral Reef Studies. You can see distressing before-and-after photos of bleached coral on the Daily Mail’s website here.

Glover's Atoll Coral

The Belize Barrier Reef System - The Belize reef is the largest continuous reef system in the Western Atlantic. It includes about 6,000 square kilometers of lagoon, supporting over 500 species of fish, 100 different types of coral species and hundreds of invertebrate species like starfish and sea urchins. Rising ocean temperatures and hurricanes, which are also linked to climate change, are responsible for most of the damage this ecosystem has suffered. But humans have also had serious and negative impacts, reports the Asenk Belize Barrier Reef blog, including overfishing and runoff from coastal development. While tourism is one of Belize’s greatest sources of income, cruise ships pose a threat to reefs by crushing reefs with their anchors and propellers, polluting the water with oily bilge water and polluting the air with exhaust.

Crosshatch Butterflyfish

The Philippines - The coral reefs of the Philippines are the second-largest in Southeast Asia. They support hundreds of species of corals and fish, all of which are endangered by direct human activity as well as climate change. The reefs lie within the Coral Triangle, which includes more than 75 percent of all coral species and 35 percent of the world’s coral reefs, reports the Union of Concerned Scientists. Their economic worth is valued at more than U.S. 2 billion annually due to the fishing, tourism and storm protection they provide. Unfortunately about 98 percent of Philippine reefs are classified as threatened. UCS says that 70 percent are at high or very high risk. Major threats come from destructive fishing methods using explosives and poison (cyanid fishing for the aquarium trade), excessive fishing, pollution runoff from logging, agriculture and urban development. 

School of snappers, Cayo Largo

The Caribbean - Only 8 percent of the Caribbean’s reefs today retain coral, says the International Union for Conservation of Nature (IUCN), due to “overfishing, pollution, disease and bleaching caused by rising temperatures resulting from the burning of fossil fuels.” Forty years ago, over half of the reefs in the Caribbean sported coral. But after decades of human impacts, only remote reefs in the region show coral growth up to 30 percent, still just over half that found in 1970, reports Monga Bay. “It’s a dire picture,” says Carl Gustaf Lundin, director of IUCN’s Global Marine and Polar Programme.

What Can You Do To Help Protect Coral?

Because coral are so slow-growing and vulnerable to pollution and climate change, it’s essential to do what we can to protect them. Here are some suggestions:

  • Never anchor on a reef.
  • When snorkeling or diving, don’t break off pieces of coral and make sure to avoid hitting coral when you kick your fins.
  • Support organic agriculture to reduce toxic runoff.
  • Support policies that limit coastal development and encourage coastal communities to contain trash and stop wastewater dumping into the sea.
  • Encourage elected officials to set aside coral reefs as marine sanctuaries that are protected from fishing and development.
  • Volunteer with organizations working to clean up local waterways. The health of all waterways—rivers, lakes and bays—ultimately affects the ocean.
  • Slow global warming by conserving energy, which includes using energy-efficient lighting and appliances and using mass transportation whenever possible.

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Siyus Copetallus
Siyus C2 years ago

Thank you for sharing.

LF F2 years ago

Oh my gosh, the vibrant beautiful colors. How can anyone not believe that there is a miraculous God?

Iskrica Knežzevic

thank you!

Jim Ven
Jim Ven2 years ago

thanks for the article.

Sharon B.
Sharon B2 years ago

Thank you for sharing.

Deborah W.
Deborah W2 years ago

Willing to bet these are old pics ... nothing is left this pure given all the dumping, overfishing, rerouting, technology implants, etc. What say you ...

Danuta Watola
Danuta W2 years ago

Thank you for sharing.

william Miller
william Miller2 years ago


Marie W.
Marie W2 years ago

Threatens All Coral Reefs.

Natasha very busy
Past Member 2 years ago

Such a shame. All that's beautiful about this earth is dying still we flourish--so unjust.