Coral Reef Ecosystems

Learn more about the importance of coral reefs, the species they support, and reef restoration efforts. Explore NOAA’s work in studying and protecting these areas and how national marine sanctuaries benefit coral reef ecosystems.


Coral Basics

Hard corals are the building blocks of coral reefs, and the mainstay of the coral cap at Flower Garden Banks National Marine Sanctuary. Soft corals are completely missing from this area of the sanctuary.

Fishes swimming with corals in their surroundings

Corals Tutorial

The tutorial is an overview of the biology of and threats to coral reefs, as well as efforts being made to conserve and protect them. It includes images, animations, and videos.

Stacks of coral reefs

Earth is Blue Magazine: Coral Reefs

Coral reef ecosystems are some of the most diverse ecosystems: thousands of species rely on them for survival. They are also crucial to human communities, protecting coastal populations from storm damage, supporting commercial fisheries, attracting tourists, and more.

Coral reef in florida keys

Corals and Coral Reefs from the Florida Keys National Marine Sanctuary

Florida Keys National Marine Sanctuary protects North America's only coral barrier reef. These reefs are intricately tied to our area’s economy, attracting tourists for diving, snorkeling, and other recreational opportunities and providing homes for many commercially important fish species.

Coral reefs

Coral Reefs in American Samoa

Coral reefs are among the oldest and most diverse ecosystems on Earth. Even though they cover less than one percent of Earth’s surface, it is estimated that they support more than 25 percent of all marine life.

Coral reef in florida keys

Shallow Coral Reef Habitat

Coral reefs are underwater structures built by tiny sea animals. Their beautiful shapes and colors are a magnet for divers, but they also provide an excellent home for thousands of marine creatures, including fish we love to eat.

Coral Spawning

Coral Spawning in Flower Garden Banks National Marine Sanctuary

Every August, the reef-building corals of Flower Garden Banks National Marine Sanctuary put on a fantastic spawning display. It is one of the most abundant coral spawning displays in the entire Caribbean due to the high density cover of broadcast spawning species.

Coral reef disease map

Florida’s Coral Reef Disease Outbreak

Florida's Coral Reef is experiencing a multi-year outbreak of stony coral tissue loss disease. While disease outbreaks are not uncommon, this event is unique due to its large geographic range, extended duration, rapid progression, high rates of mortality and the number of species affected.

Restoring coral reef diver

Restoring Coral Reefs

Coral reefs provide coastal protection for communities, habitat for fish, and millions of dollars in recreation and tourism, among other benefits. But corals are also severely threatened by rapidly worsening environmental conditions. Learn how NOAA works to restore these valuable habitats.