Spectacular night dives are nothing new to the Florida Keys, however, dives on or around August 26th or September 24th, 2018 will have something extra special. Those dates are full moons, and it is the time of the year to witness Coral Reef Spawning in the region.
Although the exact reasons that trigger corals to spawn are not exactly understood, there is strong evidence to indicate that there is a connection to lunar cycles, tide, water temperature and 24-hour light cycles. The event is monitored by scientists every year, with a reasonable degree of accuracy of prediction when the next event will be.
Coral spawning takes place as a mass event when corals time the release of there sperm and eggs at the same time. After fertilization, the larvae float on the surface for several days before sinking to the bottom and starting to form new polyps and ultimately corals.
Check out the video below of coral spawning in the Florida Keys.
From Florida Keys National Marine Sanctuary. Sometimes corals will release just their male gametes, which will then be fertilized inside female coral polyps. But, the most impressive sight is the more common “broadcast spawn” where male and female gametes are released in unison to mix and fertilize in the water column and float to the surface. The fertilized baby corals will drift in the ocean currents for weeks before settling on the seafloor where they will hopefully grow into new reefs.
Divers interested in viewing Mother Nature’s romance at work should be prepared for a late evening of night diving, and be patient. While scientists have narrowed down the window of coral spawn nights, much of the timing is still a mystery and can be affected by weather and other environmental factors. As spawning begins, keep an eye out for tiny white, pink or orange spheres rising out of the center of each coral polyp, coral colonies which appear to be “smoking,” and the frenzied behavior of nearby fish.
Divers aren’t the only ones interested in spawning corals. Fish and marine life are in tune with this cycle, too, and eagerly await the spawn so they can feed on the gametes. Fortunately, the nature of the large broadcast spawn actually gives baby corals the advantage against hungry predators. Much of the fun of coral spawn is watching the entire reef community come alive for the celebration and the feast.