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Grampus griseus

Risso's Dolphin

Order: Cetacea
Family: Delphinidae

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Conservation Status: Least Concern.


Much of what we know about Risso's dolphin, also called grampus, comes from studying stranded animals. They inhabit deep tropical and warm-temperate waters worldwide, usually where the water is deeper than 180 m, making them hard to study. The remains found in stomachs show they prey upon squid exclusively. Scars are often found on their skin, which may be the results of wounds produced by squid beaks and tentacles. Some researchers believe these marks may also reflect the highly physical ways these dolphins interact - by slapping, splashing, and leaping on one another. Risso's dolphin is highly social. Hundreds of them have been seen swimming on the surface, leaping clear of the water, and "bow-riding" on waves, sometimes with Pacific white-sided dolphins and northern right whale dolphins.

Also known as:
Grampus, Gray Grampus, White-headed Grampus

Sexual Dimorphism:
None

Length:
Range: 2.8-3.8 m

Weight:
Average: 500 kg
Range: 400-600 kg

References:

Cuvier G., 1812.  in Nouvelles annales du Muséum d’histoire naturelle, Paris, Tome 19, p. 13.

Links:

Mammal Species of the World

Distribution of Grampus griseus

Image of Grampus griseus
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