About Cuttlefish

Cuttlefish, or Sepia officinalis, are the chameleons of the sea with the ability to change color instantly. They are cephalopod mollusks in the same family as octopus and squids; but most bird-lovers know about them because their calcium-rich cuttlebone is used as a source of calcium for cage birds. Cuttlefish have a very large brain and eye in relation to their body size and are considered one of the most intelligent invertebrates. There are about 120 known species of cuttlefish.

  1. Description

    • Cuttlefish have a flattened, broad head ending in eight short tentacles and two longer ones that are kept hidden. In the center of the tentacles the cuttlefish has a sharp beak similar in appearance to a parrot's beak. The large eyes have a W-shaped pupil. The body or mantle is broad and flattened with a flexible fin running all the way around it. Inside the mantle is the elongated cuttlebone, actually an internal shell. The largest species is the Australian giant cuttlefish (Sepia apama), which can weigh over 23 lbs. and have a mantle up to 20 inches long. Most species are much smaller with the smallest being just 6 inches long.

    Range

    • Cuttlefish are completely absent from the Americas but otherwise widely distributed in the tropics and subtropics as far north as Great Britain. It is thought that the cold, deep waters of the Atlantic and Pacific Oceans have prevented cuttlefish from colonizing the Caribbean and the American coasts. Cuttlefish are present all around East and South Asia as well as Western Europe, the Mediterranean Sea and the entire seaboards of the African and Asian continents.

    Habitat

    • Although known to dive to depths of 2,000 feet, most cuttlefish species live in shallow water no deeper than 320 feet where some light penetrates. They prefer flat bottoms where they can rest motionless and almost invisible on the substrate.

    Behavior

    • The cuttlefish is an ambush predator that relies on its remarkable ability to change color instantly and its stealthy movements to sneak up on fish and crabs before grabbing them with its two long tentacles. Cuttlefish use elastic, sac-like pigment organs in their skin called chromatophores to change colors and can even vary the texture of their skin to match the background.

      All species can move backwards by jet propulsion by forcing water through a siphon tube just below their heads. They also release a dark brown ink cloud if threatened. Males often fight before mating with females and adults of both sexes die after breeding. Females lay bunches of grape-like eggs in caves and under rocks.

    Uses

    • In most places where cuttlefish are found they are eaten; they can be dried as a snack as in Southeast Asia, cooked in stews or fried. In Italy their ink is used to make black pasta and in Spain it is used to flavor black paella. Their ink was once used to prepare sepia dye although this has now largely been replaced by artificial dyes. Cuttlefish can also be kept by specialists in large seawater aquariums and their cuttlebone is still used as a source of calcium for birds and reptiles.