The beautifully marked Caribbean Spiny Lobster has long been a Florida seafood favorite and is arguably one of the state’s most important fisheries. Thousands of harvesters flock to the Florida Keys each year during the sport and regular season to experience some of the best lobstering in the world. Many divers, like the one in our video, often encounter egg-bearing spiny lobsters. These egg-bearing females have tens of thousands of orange or brown eggs under their tail and are illegal to harvest. The use of a measuring device is required at all times, and spiny lobster must have a minimum carapace length of greater than three inches. The measurement must also take place in the water. The carapace is measured beginning at the forward edge between the rostral horns and proceeding along the middle to the rear edge of the carapace. It’s the little things that go a long way toward conserving this important species!

Caribbean Spiny Lobsters, Panulirus argus Description & Behavior

Caribbean spiny lobsters, Panulirus argus (Latreille, 1804), aka Florida spiny lobsters, grow to about 60 cm in length. Like the other 20 members of the genus Panulirus, such as the Australian, California, and Chinese spiny lobsters, they lack the large pinching claws of their Maine lobster relatives. Their primary defense are the spines that cover its shell, which help protect them from predators. Caribbean spiny lobsters use a second pair of antennae in sensory perception, which are found folded along side their body when it’s not in use. These lobsters have a striped body, brown-gray in color with yellow spots on the segmented tail. They also have compound eyes and can detect orientation, form, light, and color. If startled, these lobsters will kick their large abdominal tails rapidly to swim away backwards to safety.

Spiny Lobster World Range & Habitat

Caribbean spiny lobsters, Panulirus argus, inhabit tropical and subtropical waters of the Atlantic Ocean, Caribbean Sea, and Gulf of Mexico. This nocturnal species inhabits coral reefs where they hide during the day in crevices under ledges.

Feeding Behavior (Ecology)

Caribbean spiny lobsters feed primarily on gastropods, chitons, bivalves, and carrion from the ocean floor. They are also known to feed on sea urchins, worms, crustaceans, and some types of sea vegetation.

Caribbean spiny lobsters are preyed upon by many species such as moray eels and nurse sharks.

Life History

Caribbean spiny lobsters, Panulirus argus, mate between March and June using external fertilization for reproduction. Their reproductive glands are found on the sixth thoracic segment of females and on the eighth thoracic segment of males. During mating, the males pass a thick spermatophore to the females known as a “tarspot” that fertilizes their eggs. They carry the fertilized eggs externally on their thoraxes where they become hard and black. At this stage the females deposit their eggs in protected places where they grow into a larval stage and become planktonic.

In south Florida, spawning occurs from April through October when water temperatures exceed 23°C. Settlement of pueruli, the free-swimming phase linking planktonic and benthic life stages, occurs year-round. A peak in settlement usually occurs during the spring and sometimes during other seasons.

Young juvenile Caribbean spiny lobsters, about 2.5 cm in carapace length, can grow up to 1.3 cm carapace length per week. This growth rate would allow some spiny lobsters to reach 7.6 cm in about 1.5 years after settlement. In general, although male lobsters grow faster than females, most Caribbean spiny lobsters in Florida attain about a 9 cm carapace length when they are about three years old.

Conservation Status & Comments

Caribbean spiny lobsters, Panulirus argus, are a popular seafood and commercially fished. Since about 1970, the commercial landings of Caribbean spiny lobsters in Florida have varied without trend between 1,950,447-3,583,379 kg per fishing season. During the 2001 calendar year, the commercial fishery landed 1,538,837 kg in Florida.

Usually, less than a half million pounds are landed outside of the Florida Keys. Within the Keys, the fishery developed in the Key West area and expanded to the middle keys. This development occurred around 1968, when the minimum carapace length was decreased to 7.6 cm. The current fishing season opens on August 6 and closes March 31. Approximately 40% of the season’s landings occur in August, which is followed by a sharp decrease in landings thereafter. Effort also declines after the opening of the stone crab fishery on October 15. A spiny lobster trap reduction program was implemented in August 1993 to reduce excess effort in the Keys lobster fishery.