Coral reefs are one of the most diverse ecosystems on the planet and the backbone of local and regional economies.

Supporting approximately 25 percent of all known marine species, coral reefs are called “rainforests of the sea.” These reefs are intricately tied to communities and economies, attracting tourists and locals alike for diving, snorkeling, and other recreational opportunities. They provide homes for many commercially and recreationally important fish species.

The National Marine Sanctuary System harbors roughly 15-20 percent of the nation’s coral reefs, including some of the most pristine reefs in the US.

  • Florida Keys National Marine Sanctuary protects the third largest living coral barrier reef system in the world.
  • Papahānaumokuākea Marine National Monument, the largest protected area in the Northern Hemisphere, is home to the longest-living marine species in the world—black coral—the oldest of which is estimated to be 4,265 years old.
  • Big Momma, one of the largest corals in the world, is located in the Valley of the Giants in National Marine Sanctuary of American Samoa.
  • Flower Garden Banks National Marine Sanctuary features shallow coral reefs as well as deeper corals that occur in the mesophotic or “twilight” zone. Similar to shallow water reefs, these deeper corals serve as unique habitat but were previously unexplored until scientific diving and remotely operated vehicle technologies advances made them more accessible.


But the threats against corals are mounting.

Pollution and climate change is causing dramatic changes in the water quality, temperatures, and chemistry. Because corals are sensitive to environmental changes, coral serves as a “canary in the coal mine” and warns scientists about the health of the marine environment.

Corals need clean, clear water to survive. When sediment and other pollutants enter the water, they smother coral reefs, speed the growth of damaging algae, and lower water quality. Pollution can also make corals more susceptible to disease, impede coral growth and reproduction, and cause changes in food structures on the reef.

Coral bleaching events occurs when corals are stressed under the pressure of increased water temperatures, and may be exacerbated by ocean acidification and other stresses. The ocean is experiencing its largest and most damaging coral bleaching event in recorded history. These bleaching events can result in the death of a coral reef. In some cases, however, corals can recover if conditions are advantageous and other stressors, like pollution and overfishing, are removed.

Ocean acidification also affects the growth, reproduction, and health of corals. This can have cascading effects up the food chain. It also reduces the integrity of reefs themselves, putting at risk the protection they provide land masses from storms and rising seas. With coral reefs supporting 25 percent of life in the ocean, these events can have lasting impacts to marine environments and the communities that depend upon them. [godeeper_slider]


NMSF supports coral conservation, research, and monitoring.

Sanctuaries are sentinel sites where science, research, and monitoring can help to better understand the changes and impacts to corals and other marine resources and scientists and communities can explore innovative strategies for early warning, recovery, restoration, and adaptation.


Supporting Coral Nurseries for Restoration, Resilience, and Adaptation

To advance on-the-ground restoration efforts, the National Marine Sanctuary Foundation supports coral nurseries and research in the Florida Keys. These nurseries aim to replenish wild populations of corals by providing care and protection to nurse them back to health and eventually transplanting them on the reef to improve and supplement existing corals. Coral restoration efforts, like these nurseries, hope to enhance reef resilience, and citizen science initiatives actively promote stewardship and outreach to reduce additional stressors.


Uncovering the Mysteries of Coral Spawning

In the darkness of night, days following the full moon in August, scientists and researchers witness an underwater blizzard. The National Marine Sanctuary Foundation partners with academic institutions and organizations to study this natural phenomena, known as a mass coral spawning event, at the Flower Garden Banks National Marine Sanctuary. During these mass spawning events, certain corals simultaneously release their sperm and eggs producing a snowstorm of reproduction. Flower Garden Banks is known as one of the most prolific spawning events in the Caribbean due to the large colonies and high coral cover of broadcast spawning corals. The hope is that a better understanding of coral reproduction will aid recovery, and strengthen efforts to limit coastal pollutants and sediments that can interfere with successful coral spawning.


Blue Star Operators to Promote Sustainable Tourism

Florida Keys National Marine Sanctuary founded the Blue Star Program to engage and recognize tour operators and charter boats who are committed to promoting responsible and sustainable diving and snorkeling practices to reduce the impact of these activities on coral reefs. Blue Star businesses receive specialized training to educate their customers visiting these treasured places to help keep the sanctuary’ coral reefs healthy for future generations.


Preventing Anchor Damage and Promoting Sustainable Recreation with Mooring Buoys

Anchors can cause damage to coral reefs as they drag along the seafloor to secure a vessel in place. The National Marine Sanctuary Foundation supports the installation and maintenance of mooring buoys across the National Marine Sanctuary System. These buoys prove vital to conservation, sustainable outdoor recreation and local economies.


Catlin Seaview Survey: Visualizing Climate Change through Coral Bleaching Impacts

The National Marine Sanctuary Foundation partners with Google Street View and Catlin Seaview Survey to conduct underwater filming and photography expeditions. The images and videos produced provide viewers a virtual window into less accessible locations, seeing the before and after impacts of climate change and coral bleaching events, and, hopefully, documenting recovery efforts at several sites that experienced intense bleaching since 2014.