The common cuttlefish is one of the most famous and biggest of the cuttlefish species. They are indigenous to the Mediterranean Sea, North Sea, and Baltic Sea, although there has been some suspicions that subspecies of it has far as South Africa. The common cuttlefish is a large species and can attain a maximum mantle length of 49 cm and a body weight of 2 kg in temperate waters, and 30 cm and 2 kg in subtropical regions. The mantle of the common cuttlefish is basically its skeletal system along with the cuttlebone, for most molluscas do not have organic bones. It inhabits sandy or muddy environments and can tolerate colder waters. Both adults and young bury in the sand during the day and ambushes prey from its hiding place at night, feeding on a wide variety of prey including crustaceans, other molluscs, polychaetes, and small demersal fish as well as other cuttlefish. They are preyed upon by sharks, big fish and other cephalopods. During autumn and winter, individuals migrate to deeper waters (approximately 100m); returning to shallow water in spring and summer. In the Mediterranean, large males return to shallow waters ahead of females with females and smaller individuals joining them throughout the spring and summer. Males will guard females from rival males. Males have on average 1,400 sperm cells, and females can have between 150 and 4,000 eggs (8 to 10mm in diameter) depending on their body size. The eggs are attached to a range of substrates, including seaweed and shells, and are darkened with ink so that scientists can study and observe them. The duration of embryonic development is temperature dependent and ranges from 30 to 90 days. Those young that hatch in spring usually spawn in the autumn of the following year; those that hatch in autumn usually spawn in the spring of their second year. Young are restricted to shallow water until their cuttlebones(mantles) are fully formed. Growth rates are rapid leading to a life span of one to two years.