This process takes decades as boulder-type corals grow less than one centimeter per year. Thinner, branching corals grow as quickly as ten centimeters per year, but are easily broken in strong storms or as a result of human impact. The age of corals can be determined by examining coral growth rings, similar to counting rings in the trunk of a tree, or through the use of radioisotopes. The Tortugas Coral can reproduce asexually or sexually. Asexual reproduction occurs when a portion of living tissue buds off or when part of the colony is broken away from the parent colony, neither of these instances allows for genetic recombination.
Sexual reproduction is the combination of egg and sperm to form larvae.
These larvae are planktonic and exist in the water column until they settle onto an appropriate substrate and metamorphosize into a single coral polyp. The single polyp will then grow into a colony. Coral spawning is a spectacular event and one means of sexual reproduction that occurs in the Florida Keys on an annual basis. Corals have been observed releasing their gametes into the water column five to eight days after the August full moon over the past four years. This type of broadcast spawning has been known to occur on Pacific reefs, but it was not observed in the north Atlantic until 1990.