Background

The Risso’s Dolphin is a sociable species that lives in groups, generally consisting of upto 10 individuals. These dolphins have blunt rounded faces, unlike the beaks of other dolphin species. Due to the blunt faced nature of these marine mammals they can sometimes be confused with pilot whales, therefore to identify this species it is advised to look for scarring on the body, caused by prey.

Habitat

The Risso’s Dolphin lives in all tropical and temperate seas. Migrating from warmer habitats in the winter, and cooler waters in the summer.

Diet

These animals dive deep in order to find their favourite prey of squid and small fish. They work in co-ordination in order to round up shoals of their prey.

Predators & Threats

Like a number of marine mammals the biggest threats facing the Risso’s Dolphin include; direct hunts (primarily in Taiwan and Japan), climate change and entanglement in fishing gear. Whilst they are quite large, these dolphin are the prey to a number of large sharks such as the bull, tiger and great whites, along with the killer whale or orca.

Facts

  • Risso’s dolphins have 4-14 teeth in the bottom jaw, but there are rarely any found in the top jaw.
  • These dolphins frequently breach and leap out of the water.
Common Name(s)Scientific Name
Risso’s Dolphin, Grey DolphinGrampus griseus
Size
3.5-4 m
Lifespan
30 years.

Best Time to Look

In the coastal waters of Britain, it is best to look for these in Summer.

Where to find Risso’s Dolphin