Toothed whale melon consists of fat, and the skull of any such creature containing a melon will have a large depression. The melon size varies between species, the bigger it is, the more dependent they are on it. A beaked whale, for example, has a small bulge sitting on top of its skull, whereas a sperm whale's head is filled mainly with the melon. Bottlenose dolphins have been found to have signature whistles unique to a specific individual. These whistles are used for dolphins to communicate with one another by identifying an individual. It can be seen as the dolphin equivalent of
Gray whale where she was rushed to SeaWorld San Diego. After 14 months, she was released because she also grew too large to be cared for in the existing facilities. Reaching and , J.J. was the largest creature ever to be kept in captivity. Gray whale The gray whale ("Eschrichtius robustus"), also known as the grey whale, gray back whale, Pacific gray whale, or California gray whale is a baleen whale that migrates between feeding and breeding grounds yearly. It reaches a length of , a weight of , and lives between 55 and 70 years. The common name of the whale