Staghorn coral is a type of stony coral found in the northern Atlantic ocean. Commonly found around the Caribbean islands, the Florida Keys, and the Bahamas, it can also be found in areas of the Gulf of Mexico and Venezuela. The scientific name for staghorn coral is Acropora cervicornis.
Also called antler coral, staghorn coral receives its common name from its superficial resemblance to deer antlers. As is typical for stony corals, staghorn coral consists of tiny polyps which secrete a hard skeleton and live together in a colony. The fastest growing coral in its native range, staghorn coral can have branches reaching up to 6.5 feet (2 m) long. Normally, individual branches will grow between 4–8 inches (10–20 cm) each year. Its age can be determined by counting the growth rings on the skeleton, just as with trees.
Living in symbiosis with photosynthetic microscopic algae called zooxanthellae, this coral receives its nutrients from the zooxanthellae. Since the algae needs sunlight for photosynthesis, staghorn coral is not found deeper than 98 feet (30 m) from the surface. Without the symbiotic algae, the coral cannot obtain sufficient nutrients.
Staghorn coral is able to reproduce both sexually and asexually. Its primary means of reproduction is asexual, by means of fragmentation. Fragmentation occurs when branches break off a colony and reattach somewhere else. This is especially advantageous when recovering from weather-based disasters which break large numbers of branches. One of the disadvantages, however, is a lack of genetic diversity when new coral is produced asexually.
Sexual reproduction occurs in staghorn coral by gametes which spawn, moving into the water column where they grow into larvae. The larvae live with plankton as they grow, eventually settling into a colony. Spawning only happens once a year however, in August and September, and few larvae survive to settle.
Staghorn coral is one of the most important corals in the Caribbean since it contributes significantly both to reef structure and fish habitats. It is, however, a threatened species, with populations declining at an alarming rate since the 1980s. In some places staghorn populations have declined by as much as 98 percent.
Factors which contribute to the decline of this coral include natural occurrences, like hurricanes, as well as human interference. The primary cause of the decline, however, is disease. Staghorn coral is often afflicted with bleaching, which causes the loss of zooxanthellae.
In an effort to combat the coral's decline, scientists have created several restoration efforts. One approach is to manually reattach fragmented coral. This does not help with disease issues, however, since asexually reproduced coral will have the same increased likelihood of disease as its parent coral. An additional approach is to introduce cultivated larvae into the reef environments in an effort to provide greater genetic diversity.