Coral Reefs

Called the “rain forests of the sea,” coral reefs are important ocean ecosystems that support a quarter of all marine organisms despite covering less than one percent of the sea floor.

FEATURES

Blog entry
The pre-industrial American landscape was once rightly described as a place where “the deer and the antelope roam.” On land, we take it for granted that the plant-eating deer and antelope far outnumber the...
If you look closely, you can read a message in the corals. We are not being...
The majestic and highly predatory red lionfish ( Pterois volitans ) , native to...
Blog entry MORE STORIES Blog entry MORE AUDIO / VIDEO
Reef biologists over a certain age are haunted by memories of what glorious...

LATEST CATCH

Compare the healthy coral on the left with the bleached coral on the right. Increased water temperatures caused the bleached coral to lose the microscopic algae that give the coral color and provide it with food. Corals can...
The Oculina deep-sea coral reef at top has not been disturbed by humans—but...
What are corals? Corals themselves are animals. But tropical reef-building...

DIVE DEEPER

Coral reefs are the most diverse of all marine ecosystems. They teem with life, with perhaps one quarter of all ocean...
In this photo of a shallow coral reef in the Pacific there are three species of forams . On the left, Peneroplis planatus . In the center, Amphistegina lessonii . And on the right, Laevipeneroplis sp...
The Tubbataha Reefs National Park site in the Philippines was inscribed on the World Heritage List in 1993. The site is an example of a pristine coral reef with a spectacular 100 m (330 ft)...
Nestled among the beautiful coral reefs of Papua New Guinea (PNG) is a place that could provide the key to our understanding of one of the biggest threats to coral reef survival: Ocean Acidification...
When we think "Africa," we think of the "Big Five"—lions, elephants, leopards, buffalo and rhinos—that crisscross the African Savannah. Few would imagine that there could be more natural beauty on...
Dr. Carole Baldwin , a research zoologist and fish expert with the Smithsonian's National Museum of Natural History, gives viewers an inside-look at the Deep Reef Observation Project (DROP). She and...
A master of disguise, the pygmy seahorse ( Hippocampus bargibanti ) grows to only 2cm in length and matches the gorgonian coral that it lives on. The pygmy seahorse is so successful at hiding that it...
A variety of organisms make their home on this tropical coral reef in Indonesia. More about coral reef ecosystems can be found in the Coral Reefs section .
How does a coral spend its day? Most of us would say: not doing much. To the human eye, a coral looks relatively still, waiting in the current and hoping some food will run into its tentacles. But...
The branches of a primnoid coral in the genus Calyptrophora provide a habitat for galathaoid crabs. Learn more about the deep-sea coral reefs in our Deep-sea Corals article .
Scientists have been studying why populations of crown-of-thorns sea stars ( Acanthaster planci ) have mushroomed in recent decades. Coral reefs can suffer when the sea star's numbers explode because...
Dead man’s fingers ( Alcyonium digitatum ) are soft corals named for their appendage-like appearance when thrown ashore by storms. The finger-like clumps of coral polyps come in various shades of...
The “Hyperbolic Crochet Coral Reef,” a unique exhibition and thought-provoking fusion of science, conservation, mathematics, and art, is on display in Washington, D.C., at the Smithsonian’s National...
The Ujung Kulon National Park in Indonesia was inscribed on the World Heritage List in 1991. The park, located in the extreme western tip of Java on the Sunda shelf, includes the Ujung Kulon...
This photo of Kingman’s Reef in the Line Islands shows what a healthy coral reef should look like. The water is crystal clear. A variety of richly colored corals carpet the seabed. And a native...
Algae has overtaken this coral reef off heavily populated Kiritimati, or Christmas Island. Few fish swim in the murky waters. The causes include pollution, overfishing, and increased water...
This bluefin trevally is lucky to call Hawaii’s Maro Coral Reef, part of the Papahānaumokuākea Marine National Monument , its home. Maro is the largest reef in the Northwest Hawaiian Islands and just...
Dr. Stephen Cairns is a research zoologist and chair of the Department of Invertebrate Zoology at the Smithsonian’s National Museum of Natural History. His research focuses on the diversity,...
This coral reef in the Western Pacific Ocean was killed by human input of silt and sand from nearby islands reaching the coral reef habitat. More about coral reef ecosystems can be found in our Coral...
Subscribe to Coral Reefs