Risso's Dolphin (Grampus
Facts about Risso's Dolphins
Risso's dolphins, also known as Grampus, are
one of the larger types of dolphins.
Because of their size, they are usually in the deeper parts
of the ocean rather than along the shores. They live in temperate
and tropical waters worldwide.
are easy to identify because of the crisscross
scratch marks on their bodies. These markings
increase over time and may be caused from teeth marks of other
Risso's dolphins, squid bites and parasites.
Risso's dolphins are gray
with a white underside. This white patch is
shaped like an anchor. As they get older they become lighter
in color because of all of their scratch marks. They are blunt-headed
and beakless with a tall,
pointed dorsal fin and flippers.
Baby Risso's (calves) are born light gray and darken as they get older.
They are about 1.2-1.7 meters (4 - 5.5 feet) in length at
Adult Risso's are roughly anywhere from 2.6
to 3.5 meters (8.5 to 11.5 feet) in length.
They weigh and
average of 300 - 500 kg (660 - 1100 lbs).
Risso's dolphins eat squid and fish. It is estimated
that they live between 20 - 40 years.
These dolphins are sometimes seen in small groups
(pods) of 3 - 50 individuals. But they have also been seen
in very large groups of up to 4000 dolphins. Sometimes Risso's
dolphins are found swimming with other types of dolphins,
especially the Bottlenose dolphin.
Find out more about Risso's Dolphins!
- American Cetacean Society - Risso's Dolphin
- Whale and Dolphin Conservation Society