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Risso's dolphin

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Risso's Dolphin
Scientific classification
Kingdom: Animalia
Phylum:Chordata
Class:Mammalia
Order:Cetacea
Family:Delphinidae
Genus:Grampus
Species:griseus
Binomial name
Grampus griseus

The Risso's Dolphin (Grampus griseus) is a species of dolphin.

Taxonomy

Physical description

The most obvious feature of this large (up to 3.8m) dolphin is the large dorsal fin, superficially like that of a young or female Killer Whale. The main body colour is very variable, from dark grey in young animals to almost white in old adults. The underside of this heavily built animal is white. Older animals are usually heavily scarred from confrontations with other Risso's or with squid.

The head profile is almost square, somewhat like a Sperm Whale, and the flippers are long and tapering. It will form moderately sized groups, and will mix with other dolphins, but it is not particularly attracted to ships.

The Risso's Dolphin eats mainly squid and fish.

Population and distribution

It is found worldwide in temperate and tropical waters, usually in deep waters rather than close to land.

Human interaction

References

  • National Audobon Society Guide to Marine Mammals of the World ISBN 0375411410
  • Encyclopedia of Marine Mammals ISBN 0125513402
  • Whales, Dolphins and Porpoises, Mark Carwardine, ISBN 0751327816