As lobster season ends for a few month here in Florida, I thought it would be kinda cool to check out how spiny lobsters reproduce, what turns them on and why. I was diving the other day and was pretty sure that one of the duo of lobsters I saw was mating. I know from the behavior that this was what was going on now. Refer to my video from a few days ago at Pepper Park. I also spotted a group of three under a ledge, 2 small mommas with tails curved. (not legal size)
Spiny lobsters mate during the day. It is generally the males on the prowl you are seeing walking about during the day. In south Florida, spawning occurs from April through October when water temperatures exceed 73 degrees Fahrenheit. I know this has been a conversation on many scuba forums I look at daily. The little lobster larvae stages occur year round if conditions are right. That means we are going to be seeing some early hatching this year as mating has already begun.
Caribbean Spiny Lobsters reproduce from early spring to mid summer. They reproduce sexually, meaning they need a partner. They mate between March an June and use external fertilization for reproducing. The females carry up to one million bright orange eggs underneath the tail until they are ready to hatch. These females are called “in berry”. She is also called at gravid female lobster. (meaning egg bearing) The female lobster’s reproductive glands are found on the 6th thoracic segment while the males sex organs are found on the 8th segment. An easy way to tell a female is when her tail is curved. It is very noticeable. She holds the eggs in place with her little legs.
During lobster breeding season, the males lobsters leave their little holes, cracks and crevices during broad daylight on the hunt for a lovely lady. The lady lobster stays hidden during the day. This is where it gets a little rough…once a male has found a his lady lobster, he uses his front legs to grasp her gently and pull her out of her cave headfirst. The lobster will then slide his body under hers so that the lobsters rest belly-to-belly. This is called the spawn transfer. While beneath the female, the male shudders as he transfers his sperm sac to the female. This thick sperm sack is called a tarspot. The female then retreats immediately back into her hole.
When the female’s eggs are ready to fertilize, she breaks the sac open the tarspot to distribute the sperm on the eggs. The females then carry the fertilized eggs externally until they become hard and dark brown or black. They turn colors a few days before hatching. When they hatch, the females deposit their eggs into protected places where they will grow into larvae. Momma lobster helps them get on their way with quick fluid movements of her abdomen. When the larvae hatch they will travel as plankton in the ocean’s currents until they settle in shallow nurseries like mangroves and rubble reefs.
With all this said, the juvenile spiny lobsters will grow about 1.3 cm a week. They will reach 7.6 cm in about 1.5 years. Male lobsters generally grow quicker. It takes them about 3 years to grow to 9cm in carapace length which is just about legal for taking. I write this because as conditions are early for mating this year, we will not see the benefits of the warm water experienced this year for three years.
The baby lobsters will face many predators before it will reach maturity. I know many fellow divers have personally gone on the LION HUNT for the invasive Lionfish. This guy has a voracious appetite for juvies. The lionfish can consume over 20 small (1-3cm) wrasses in a 30 minute period. Lionfish stomachs can expand over 30 times it’s original size when consuming a large meal. This is a lot of little baby lobsters. I have yet to see one of these guys while diving, but I have seen other divers, taking out dead Lion Fish they have killed from these same dive spots. This past week, a few were killed in BHB area.
Anyways, with the waters being so warm this year and mating season already in full swing, I wonder if it will make them harder to catch come August. Will they have laid all their eggs and now are hiding out until next season?
Time will tell.