FLORIDA KEYS (CBSMiami/FKNB) – Several colonies of laboratory-raised mountainous star coral, a reef-building boulder coral, were observed spawning in the Florida Keys National Marine Sanctuary earlier this week by researchers from the Keys-based Mote Marine Tropical Research Laboratory.

The breakthrough, the first spawn ever for lab-raised restored massive corals, according to Mote Marine officials, took place on a reef south of Big Pine Key. Spawning, part of sexual reproduction sometimes characterized as “sex on the reef,” is often described by divers as resembling an upside-down underwater snowfall.

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During spawning, corals release their gametes (eggs and sperm) into the water column. The gametes move with currents and can settle on the sea floor to eventually create new coral colonies.

With reefs around the world threatened by challenges such as global warming, many scientists believe that the efforts to restore coral can only be truly successful if laboratory efforts result in spawning.

Mountainous star coral, listed as threatened under the U.S. Endangered Species Act, helps form the backbone of Florida’s Coral Reef.

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Through a microfragmentation-fusion process pioneered by Mote researchers in the Keys, the slow-growing mountainous star corals can have their growth accelerated to reach sexual maturity in just five years.

It’s not the first time cultivated coral has spawned in the Keys.

Researchers at the Key Largo-based Coral Restoration Foundation saw their nursery-raised staghorn corals first spawn in 2009.

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