Spawning Goliath: Grouper Spawning Season

Spawning Goliath: Grouper Spawning Season

Hello, divers of south Florida! It’s September, which means one thing, grouper spawning season. This time of year deep-sea explorers get the chance to take in and behold the spectacle that is the mating habits of one of the largest fish species of our coastal waters.

Sure, there’s a good chance we’ve all come across grouper at some point in the duration of our time in Florida, whether it’s during an excursion into one of our many coral reef systems that grow all across the coastline, or perhaps even on our dinner plates. One thing is for certain, the spawning ritual of the Goliath Grouper is an event to behold in itself.

Rite of Replication

The Goliath’s spawning season occurs during the warmer summer months, stretching across July, August, and September. It is noteworthy to add that the goliath grouper’s cycle is largely influenced by the lunar cycle as well.

During breeding cycles, a staggeringly large number of fish congregate, sometime forming schools climbing over 100 members. Typically, the select areas like shipwrecks, secluded patches of reef, and rock ledges to perform their spawning ritual. The males release sperm as the females release their eggs into the open waters. Once fertilized, the eggs become subject to the tides, going whichever way the waters flow. The begin life as kite-shaped larvae, eventually reaching a juvenile stage of maturation at about 25 days after hatching.

Gargantuan Wonders of the Deep

It is no accident that the title “Goliath” was added to this particular species. At full maturity, they can span body lengths of up to 8 feet long, and weighing in at a whopping 800+ pounds. A truly massive denizen of the reef!

Males reach sexual maturity at around age 6, where they would then be at their greatest size and stature.

The oldest recorded Goliath Grouper lived to the grand old age of 37. Their size begins to decline at around 15 years, where they continually lose weight and length in small increments annually.

Take a moment and watch this video which was taken from a recent dive at Danny McCauley Memorial reef. We spotted tons of Goliath Grouper here for spawning season. This video really demonstrates the colossal size of these amazing creatures!


The Goliath Grouper can be found in the waters surrounding the southwestern coast of Florida (namely, the Florida Keys) and occur in high frequency along the coastal waters of Brazil. In less frequent sightings, they have been observed along the pacific coast of the United States and even down alongside Peru.

They are permanent residents of the coral reef’s ecological system, set in their ways and rarely venturing outward into open waters. They’ve also been known to take up residence inside old shipwrecks and underwater caves. Any dark, secluded area is home to them.

The Goliath Grouper is truly a juggernaut of our waters. We are blessed to have such a gargantuan guest right here in our own backyard. Divers of Florida would do well to marvel in the glory of their presence.