Rissos Dolphin

Name : Risso's Dolphin

Scientific Name : Grampus griseus

Class : Mammalia

Family : Delphinidae

Order : Cetacea suborder - Odontoceti

Shape : The body is generally sturdy, and the part behind the dorsal fin is slender. The melon is huge and divided by a slight vertical linear depression running from the forehead to the mouth. The snout is almost non-existent. There are only one or two vestigial teeth on the upper jaw and three to seven large cone-shaped teeth on each side of the lower jaw.

Fins : The dorsal fin is median, falcate, predominant, and high - about 40 cm. The pectoral and caudal fins are long in comparison to those of other cetaceans, and the tail has a median notch. The fins are black.

Length : It measures between 3 - 4.30 metres, and the newborn from 1.40 to 1.80 metres.

Weight : Its average weight is between 300 - 680 kg.

Colour : The adult's body is dark grey, with a long white area on the throat, chest, and stomach. Young animals have a yellowish head and are generally lighter-colored than adults. As these cetaceans age, they are covered with linear scars that result from tooth marks left by their fellow mammals or cephalopods; some are so covered with these gashes that they are almost completely white.

Diet : Due to its dentition, Risso's Dolphin feeds mostly on cephalopods and occasionally on fish.

Population : It is common in warm and temperate waters.

Migration : There are probably some seasonal migrations in the North Atlantic. It goes north in the summer and south in the winter.

Habits : Risso's Dolphin is a spectacular jumper, which is rare for such a massive animal. This cetacean is gregarious, swimming alone, in couples, or in groups of five or more in areas where it is abundant.

Distribution : Risso's Dolphin is found all over, but mostly in deep temperate and tropical waters.