Risso’s dolphin can dive up to 300 m and hold their breath up to 30 minutes. However, the average dive depth is 50 m and can last up to 10 minutes. They feed mainly on deepwater squid and octopuses, sometimes cuttlefish. Most feeding appears to occur at night or late afternoon.
Risso’s dolphins are typically found in groups of 10 to 30 animals. Males group in highly stable social units, while females form nurseries during calving season.
During day time they regularly socialise, rest or travel. When socialising, they can breach, spyhop, lobtail and slap the flippers. One characteristic behaviour of Risso’s dolphin is the head standing. The animal stands in a vertical position with the head underwater and the tail out of the water.
Lifespan and reproduction
Individuals become sexually mature when they are 8-10 years (female) 10-12 years old (males). The gestation period lasts approximately 13 to 14 months. Female give births to a single calf every 2-3 years all year round with regional peak in spring, summer or autumn. Newborns are 1 meter to 1,67 meter long and weigh about 20 kg. A Risso’s dolphin can live up to 50 years.