Marvelous Mollusk

Al Hornsby

After sunset, on reefs throughout the Caribbean and tropical Atlantic, one of the ocean’s most lovely octopuses can be seen prowling across the bottom or perched atop some small prominence, watchful for prey. With the ability to rapidly change colors and to move in a variety of ways, including flowing across the bottom, walking on the tips of its eight, sucker-covered arms or swimming through the water by pulsing its arms and body (it can also use its funnel for water-jet propulsion), the Caribbean Reef Octopus is a skillful predator. It is extremely interesting as well.
Like other octopuses, cuttlefish and squids, the Caribbean Reef Octopus is a mollusk of the Cephalopod (meaning “head-foot”) group. Cephalopods are found only in marine waters (none live in fresh water), but in virtually every niche, from cold to tropical waters and from the shallows to great oceanic depths. One of about six octopuses that will commonly be seen in the Caribbean by divers, the Caribbean Reef normally will be found only at night, hiding in dark recesses during the day. Similar in appearance to the Common Octopus, which will be out in daylight hours, it can be distinguished by a dark ring around the eyes and the absence of dark rings around the suckers, some 200 on the undersides of each of its arms (the opposite of the Common Octopus).
Feeding chiefly on crabs and other crustaceans (although they will also eat shells and fish), they capture their favorite prey by grabbing them with their suckers, turning them over and biting through the soft undersides with a sharp beak located at the center of their bodies, at the base of the arms. When they are seen at night, they often show little concern at a diver’s presence and can be easily followed and observed as they move about.
Considered quite intelligent for lower animals, octopuses such as the Caribbean Reef are also diligent mothers. After laying about 100 small eggs, the mother broods over them, cleaning them with the tips of her arms and jetting streams of water over them with her funnels. When the babies hatch, they are fully-formed and can hunt immediately—no training necessary. To avoid becoming some fish’s appetizer, they can use an ink blast to foil predators, from the moment of birth.