Risso’s dolphin fact sheet

Risso’s dolphins are distinguished by their robust build and rounded head, and by their extensive white body scars. They are born dark grey  and accumulate more scars throughout their life until they are almost white at maturity. These scars may be caused by encounters with other Risso’s dolphins and from their major prey item, squid. Risso’s dolphins prefer deep oceanic waters in temperate and tropical zones.

In the Azores, Risso’s dolphins typically form small groups of fewer than 15 individuals. They often associate with squid fishing boats and occasionally also with groups of bottlenose dolphins and pilot whales. Risso’s dolphins can be very active at the surface, and they are sometimes seen breaching and lobtailing.

Length: 
• Male: 3.8 m
• Female: 3.7 m
• Calf: 1.1 – 1.5 m

Weight: 
• Male: 500 kg

Global population: Unknown (population trend unknown)

Status: Least Concern

Diet: Squid, crustaceans

Teeth: 4-14, usually only in the lower jaw

Longevity: 20 – 30 years

Breeding age: Unknown

Gestation: 13 – 14 months

Nursing: Unknown

In other languages
Portuguese: Golfinho-de-Rissos, Grampo
Spanish: Delfín de Risso 
French: Dauphin de Risso
Italian: Grampo, delfino di Risso
German: Rundkopfdelfin
Dutch: Gramper, grijze dolfijn
Swedish: Rissos delfin
Norwegian: Arrdelfin
Danish: Rissos delfin
Finnish: Rissondelfiini
Polish: Risso szary
Russian: Servyy delfin