Staghorn Coral In The Virgin Islands — On The Brink of Extinction
Staghorn coral (Acropora cervicornis) is an ancient coral that can still be seen on the reefs around St. John, U.S. Virgin Islands, but it is on the brink of extinction. Encountering small patches is the norm, as the larger thickets have mostly disappeared.
Our world is changing, and nowhere is that change happening faster than in the oceans. A new class of tourism has even emerged, driven by the desire to witness parts of the Earth that are vanishing before our eyes, from the Antarctic glaciers to the staghorn coral, whose branching structure resembles the regal antlers of a 500-pound red stag.
While “last chance” or “doom tourism” is often criticized, many view it conversely as regenerative or responsible travel, since it is an effective way to raise awareness and fund conservation efforts. This is especially true when tourists book small, low-impact boat tours around St. John with our knowledgeable captains, as opposed to traveling en masse via cruise ship.
Staghorn coral around St. John USVI - Image credit: Jason Siska / Island Roots Charters
2025 Staghorn Coral Status In The Virgin Islands
As of 2025, staghorn coral in the USVI is considered critically endangered. Locals report on Reddit that it can still be seen around St. John, but one need only look to Florida, where staghorn is considered “functionally extinct” to see its future in the Virgin Islands, if the collapse continues.
Ross Cunning, Ph.D., a research biologist and coral expert with Shedd Aquarium, noted that “heat stress comparable to Florida’s 2023 event occurred across much of the Caribbean in both 2023 and 2024. Given that staghorn and elkhorn corals are among the most heat-sensitive species, impacts were likely severe. Reports suggest high mortality in some areas, while other locations have seen some corals survive.” As a disclaimer, he adds that he does not have specific data on staghorn corals in the Virgin Islands or the broader Caribbean.
What’s Killing It
Staghorn coral has been dying off en masse because of pollution, disease, ocean warming, and acidification. It all started in the early seventies and eighties when a severe white band disease outbreak event caused major species mortality. White band only attacks acroporid corals, like staghorn and elkhorn, but its effects are devastating and haunting — as it leaves behind the bone white skeleton of the coral tissue it completely destroys. Although the pathogen that causes white band disease has not been identified, Vibrio carchariae is the prime suspect.
Since then a number of additional stressors have furthered its decline:
Warming seas has led to thermal stress and bleaching. When water temperatures rise too high, the coral expels its symbiotic algae (zooxanthellae), causing it to turn white and lose its ability to photosynthesize.
Storm damage, especially from hurricanes, breaks and scatters the coral’s delicate branches.
Sedimentation smothers coral and block sunlight.
Pollution, from agricultural runoff, sewage, and coastal development.
Overfishing has reduced populations of herbivorous fish that help keep algae in check.
Ocean acidification has weakened coral skeletons and slowed its growth.
These above stressors have created a compounded effect that has left corals more vulnerable to disease and less growth, put staghorn into a downward spiral that could lead to the extinction of what was once one of the world’s most prolific coral systems.
Restoration Efforts
In the USVI, The Core Foundation and Coral World support a staghorn coral nursery aimed at saving these natural wonders. Here is a link to the 68 page pdf outlining the U.S. Virgin Islands Coral Reef Restoration Plan.
Looking to the future, Dr. Cunning adds, “The best hope for these species now lies in “gene banks” where much of their remaining genetic diversity is safeguarded in aquarium facilities on land for future restoration. These collections are being used to study and breed more heat-tolerant corals that could one day help rebuild reefs. Alongside selective breeding, scientists are also testing a range of interventions—from probiotics to gene editing—to enhance coral resilience and help them withstand future heatwaves until the climate stabilizes.”
Staghorn Coral As a Reef Builder
Staghorn coral exists as a complex three dimensional structure or thicket on coral reefs, which provides a safe habit for reef fishes and invertebrates. And it is because of its branching formation and ability to grow rapidly (4-8 inches per year - almost the same amount as a human grows during a puberty spurt!) that staghorn coral has been one of the major reef‑builders throughout the Caribbean. Other sources say that staghorn can grow up to a whole foot per year under ideal conditions.
As an individual, this coral is composed of tiny polyps that secrete a calcium‑carbonate that helps build the skeleton of coral colonies over long periods of time.
Its Place In The Food Web
Staghorn coral’s place in the reef food web is that it provides habitat for numerous organisms. The coral’s polyps host algae. It also uses stinging cells called nematocysts (and yes snorkelers and divers can get stung by them, but it usually only irritates the skin and causes a rash) to capture the nocturnal zooplankton drifting by. Then when the coral dies, algae, sponges, other corals grow on its skeleton as a substrate.
Staghorn Coral Reproduction
Staghorn coral reproduces by a process called fragmentation, which is when its broken branches re‑attach and form entirely new colonies. This super power made it one of the world’s most dominant species of coral, until recent times when it became attacked by multiple threats.
Fun fact: it is suggested that the fossilized coral skeletons of Acropora cervicornis have been dredged from harbors in the Caribbean and reused as ballast material for historical ships returning to London and Liverpool.
Scientific name and origin
Jean-Baptiste Lamarck is credited as the scientist who in 1816 provided the scientific name for staghorn coral as Acropora cervicornis. Acropora comes from the Greek word, Akron, meaning summit, in reference to the little coralitte at the tip of each staghorn coral branch. It is in the family Acroporidae, and the order of Scleractinia (stony corals).
According to genetic studies, A. cervicornis split from its Indo‑Pacific relatives around 41 million years ago.
Staghorn Coral Range
This coral, which is endemic to a variety of reef settings (patch refs, bank reefs, limestone reefs) is native to the Atlantic. It could once be found in southern Florida, where it is now considered extinct. Stagorn coral can now only be found through the Bahamas, the Gulf of Mexico, and throughout the Caribbean Sea. It also extends to the northern coastal countries of South America, i.e. Venezuela.
Staghorn Coral Depth
Staghorn coral usually likes shallow depths of less than 20 m (65 ft) because it needs light for the symbiotic algae (zooxanthellae) it depends on for glucose and amino acids. In reef zones where wave action is high, the upper depth may also be constrained because branches may break easily. However, it can sometimes be found as deep as 30 m (98 ft) or more when the light conditions allow.
Staghorn Coral Size
Branches can grow up to about 6.5 ft in ideal conditions. Fun fact: Staghorn coral grows larger than staghorn deer antlers, which usually grow to around 4 ft.
Staghorn Coral Look‑alikes
The main staghorn coral look-alike is elkhorn coral. When we consider staghorn vs. elkhorn coral (Acropora palmata), elkhorn’s “branches are broad and flattened, resembling elk antlers. Staghorn coral is far more cylindrical and slender.
The confusion really sets in with Acropora hybrids, like Acropora prolifera (called the “fused staghorn”), which share traits of both staghorn and elkhorn corals.
Elkhorn coral around St. John USVI - Image credit: Jill Siska / Island Roots Charters
Last Chance To See Staghorn Coral
Whether you are a reef lover, or an adventurer racing around the world to see a species like staghorn coral before it’s gone, now is the time visit the Virgin Islands.