Let me share some interesting facts about the Nautilus a fascinating marine creature known for its distinctive spiral shaped shell often used in jewelry and decor Habitat Nautiluses inhabit the deep waters of the Pacific Ocean ranging from the coast of Japan to the Great Barrier Reef in Australia. Anatomy They possess a multi chambered shell which helps them ascend and descend in water by regulating the gas volume within the chambers. Diet Their diet primarily consists of crustaceans and small fish which they capture using their numerous tentacles. Reproduction Nautiluses are known for their slow growth and reproductive rates making them vulnerable to overfishing.