Sealife guideThe risso's dolphinGrampus griseus
Last updated on 01/19/2026 at 11:38 PM
Taxonomy
- Common name: Risso's dolphin
- French name: Dauphin de Risso
- Scientific name: Grampus griseus (G. Cuvier, 1812)
- Family name: Delphinidae
- Order name: Cetacea
- Class name: Sea mammals [Mammalia]
Description
The Risso's dolphin owes its common name to a naturalist from Nice (France), Giuseppe Antonio Risso (1777–1845), who devoted most of his work to zoology through the study of marine wildlife in the Nice region, although he also conducted research in botany.

The risso's dolphin (Grampus griseus) © Natursports | Dreamstime.com
The Risso's dolphin is a medium-sized dolphin species, measuring approximately 10 to 13 feet in length. Its body, which becomes lighter gray over time, is covered with numerous whitish scars and markings that reflect the many interactions between individuals during conflicts or playful behavior.
Its head lacks a beak and its dorsal fin is centrally positioned, sickle-shaped and particularly tall compared to its body size.
Geographic range
Risso's dolphin is a common dolphin species in the Mediterranean sea, especially in the western basin. It is also found in the temperate waters of the North Atlantic ocean, particularly around the Azores archipelago.
Habitat
Risso's dolphin lives in small groups averaging around ten individuals, with rarely more than 20 dolphins per group. These groups usually inhabit the continental slope zone.
Diet
Risso's dolphin mainly feeds on cephalopods, especially squid, which it can hunt at great depths.
Reproduction
Risso's dolphin breeds during the summer season and a gestation period of 12 to 13 months is required before the calf is born.
Did you know ?
Risso's dolphin is one of the five dolphin species commonly found in the Mediterranean sea, along with the striped dolphin (Stenella coeruleoalba), the common dolphin (Delphinus delphis), the bottlenose dolphin (Tursiops truncatus) and the long-finned pilot whale (Globicephala melas).

The risso's dolphin (Grampus griseus) © Jaime Debrum | Dreamstime.com
The risso's dolphin is listed as many other marine species within The IUCN Red List of threatened species. The risso's dolphin appears in the IUCN Red List since 2018 within the category Least Concern !
Within the same family

Atlantic spotted dolphin
(Stenella frontalis)
(Stenella frontalis)

Atlantic white-sided dolphin
(Leucopleurus acutus)
(Leucopleurus acutus)

Common bottlenose dolphin
(Tursiops truncatus)
(Tursiops truncatus)

Indo-Pacific humpback dolphin
(Sousa chinensis)
(Sousa chinensis)

Pacific white-sided dolphin
(Sagmatias obliquidens)
(Sagmatias obliquidens)

Short-beaked common dolphin
(Delphinus delphis)
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Spinner dolphin
(Stenella longirostris)
(Stenella longirostris)

Striped dolphin
(Stenella coeruleoalba)
(Stenella coeruleoalba)
Discover also

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Dugong
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Dwarf minke whale
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Florida manatee
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Gray whale
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Sperm whale
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