Risso’s dolphin

dolphin wildlife trusts

Niki Clear

Risso’s dolphin

Scientific name: Grampus griseus
Risso’s dolphins are mysterious creatures usually only found in deep, offshore waters.

Species information

Statistics

Length: up to 4 metres long
Life span: 20 - 40 years

Conservation status

European Protected Species (EPS)

When to see

Risso's dolphins might be spotted on the water's surface where they are often active.

About

Sometimes called 'gray dolphins', the Risso's dolphin enjoys deep offshore waters. The scratches on their bodies are believed to be a result of rough behaviour including fighting and catching prey. They have been known to breach clear of the water and slap their heads or tails on the surface!

How to identify

Risso's dolphins have a robust, stocky body and large, blunt heads. They are a whiter colour than other dolphins and can be identified by the scratches and scarring often on their bodies. They have a large sickle shaped dorsal fin and their body colour turns from a dark grey to almost completely white as they get older.

Distribution

UK sightings are most common around Scotland, the Outer Hebrides and the Isle of Man. Risso's dolphins can also be spotted around Cornwall, South West and North West Wales and Ireland.

Did you know?

Risso's dolphins feed predominantly on squid and octopus. They hang out in pods of between 10 to 30 and can live for up to 35 years!

How people can help

If you spot a Risso's Dolphin, report your sighting to your local Wildlife Trust. If you spot any marine mammal whilst at sea, maintain a distance of at least 100m. If they approach you, maintain a constant speed and allow them to interact on their own terms and leave at will. If you find a stranded dolphin (dead or alive), please report it to the relevant authority.