Risso’s Dolphin

Grampus griseus

Length

10-13 feet (3-4 m)

Weight

650-1,100 pounds (300-500 kg)

Distribution

Prefer offshore habitats in warm temperate and tropical waters in both hemispheres

Population

Unknown worldwide, approximately 15,000-30,000 off the coast of California

Description

Risso’s Dolphins are one of the larger members of the dolphin family. They are dark gray in color with extensive white scarring along their bodies. The scars are mainly caused by their primary food source, squid, which utilize defensive sharp hooks on their tentacles. The scarring may also be caused by “raking” or biting from other Risso’s Dolphins.

Risso’s Dolphins typically travel in groups of 3-30 animals, although megapods of more than 1,000 have been reported. Little is known about this species, due to the fact that they are a pelagic species and are often found a very long way from shore.