The distinctly battered appearances of these dolphins make this species quite easily identified, especially as they get older and bare more scars. This extensive body scarring is caused by the teeth of other Risso's dolphins which occurs during sexual contact.

Brief Description:

• Color: Blue-gray, gray-brown, or almost white body color covered in white scars with a variable pale underside.

• Dorsal: Very tall dorsal fin, up to 20 inches high, tip may be pointed or rounded with a concave trailing edge.

• Body: Slightly bulging forehead slopes steeply to mouth. The body is robust in front of the dorsal fin. Long curved flippers with pointed tips.

• Migration: Spends winters in high-latitude, cold-water feeding grounds and summer in low-latitude, warm-water breeding grounds, migrating thousands of miles between the two.

• Habitat: Prefers deep offshore waters, but may be seen close to shore in the area of oceanic islands like the Channel Islands of central California, or where there is a narrow continental shelf.

Feeding, behavior and interesting facts:

They feed almost exclusively on squid, octopus, and also schools of fish.

Risso's dolphins rarely bow-ride, but may swim alongside a vessel or in its wake.

As the Risso's dolphin ages, their body color tends to lighten and they may become as white as Belugas, yet there is a great deal of variation between individuals. Some adult animals may become as dark as pilot whales.

The very tall dorsal fin is similar to female or juvenile killer whales or bottlenose dolphins. The Risso's dolphin can be better distinguished by identifying a species unique crease down the center of the forehead, from the blowhole to the upper "lip".

Risso's dolphins are sometimes seen mixed in with different schools of dolphins as well as swimming with pilot whales.

These dolphins are absent or scarce in the Southern California Bight during cold water periods, but are relatively abundant when warm currents dominate.