Common cuttlefish

The common cuttlefish or European common cuttlefish (Sepia officinalis) is one of the largest and best-known cuttlefish species. They are a migratory species that spend the summer and spring inshore for spawning and then move to depths of 100–200 metres (330–660 ft) during autumn and winter. They grow to 49 centimetres (19 in) in mantle length and 4 kilograms (8.8 lb) in weight. Animals from subtropical seas are smaller and rarely exceed 30 centimetres (12 in) in mantle length.

The common cuttlefish is native to at least the Mediterranean Sea, North Sea, and Baltic Sea, although subspecies have been proposed as far south as South Africa. It lives on sand and mud seabeds and it can tolerate brackish water conditions.

Behaviour

During the day, most cuttlefish can be found buried below the substrate and fairly inactive. At night however, they are actively searching for prey and can ambush them from under the substrate. Cuttlefish are carnivorous and eat a variety of organisms including crustaceans (crabs and shrimp), small demersal fish, molluscs (clams and snails), and sometimes other cuttlefish which is more commonly seen when the abundance of other prey is low.

A 2008 study on S. officinalis revealed that cuttlefish embryos, if visually exposed to a certain species of prey (e.g. crabs), will hunt primarily for that prey in later life. S. officinalis usually prefer shrimp to crabs, but when the embryos were exposed to crabs and the embryos had hatched, the young cuttlefish switched preferences and proceeded to hunt the crabs more often than the shrimp.