The Caribbean giant barrel sponge, also called the rum barrel, owes its name to its gigantic and characteristic shape, which resembles that of a barrel that in the Caribbean can only contain the local alcohol: rum !
The giant barrel sponge can be found in the Caribbean sea, notably in the 'Cousteau Reserve' in Guadeloupe !
The Caribbean giant barrel sponge has a cylindrical shape, bulging in the middle. It is sometimes possible to encounter specimens that are less round but rather slightly flattened when the sponge develops in an area subject to currents.
Ranging in color from brown to reddish, the Caribbean giant barrel sponge is hard and rough in consistency and its appearance resembles that of a « pumice stone ». Its outer surface is irregular and presents a succession of ridges and canyons. In contrast, the inner surface of the giant barrel sponge is smooth but equally rough !
The opening of the sponge, or osculum, usually has a serrated contour.
The size of the Caribbean giant barrel sponge is imposing, with measurements—enough to make anyone pale!—of more than 6.5 feet in height for a diameter of 3.3 to 6.5 feet. A sponge that makes an impression !
It may sometimes present a secondary chimney when it is located in a current zone.
Geographic range
The Caribbean giant barrel sponge can be found in the tropical waters of the western Atlantic ocean and the Caribbean sea, from Florida in the north to Brazil in the south, including the Bahamas islands. The « Cousteau Reserve » located on the Caribbean coast of Guadeloupe is home to a large population of giant barrel sponges.
Habitat
The Caribbean giant barrel sponge develops on the rocky bottom of coral reefs from a depth of 33 feet and can extend to depths of over 328 feet.
Most often solitary, you will also have the opportunity to encounter several specimens grouped together.
Diet
The Caribbean giant barrel sponge feeds on microorganisms contained in the water, which it filters throughout the day.
The outer surface of the giant barrel sponge has a particularly rugged but regular relief!
Impressive and fragile at the same time: the giant barrel sponge !
The base of the giant barrel sponge features several small chimneys !
Reproduction
The Caribbean giant barrel sponge reproduces sexually by releasing male and female gametes into the water.
Did you know ?
A food source for some sea turtles, so don't be surprised to find giant barrel sponge specimens with bite marks near their openings !
Close-up of the smooth inner surface of the giant barrel sponge !
Imposing but fragile at the same time ! Preserve this sponge, as it is the largest species of sponge in the Caribbean sea !
A method for calculating the approximate age of a Caribbean giant barrel sponge has been suggested, but what to think of the result obtained ? I'll leave that to your judgment !
Discover Fiji, a South Pacific island nation known for white-sand beaches, turquoise lagoons, coral reefs, tropical forests and traditional villages.
Friday, August 14th 2026
The reef manta ray
Discover the reef manta ray (Mobula alfredi), an impressive tropical ray that frequents coral reefs and feeds mainly on plankton.
Wednesday, August 12th 2026
The crown-of-thorns starfish
Discover the crown-of-thorns starfish, a voracious coral predator that, when populations become unusually large, can consume vast areas of coral and cause significant damage to coral reefs.
