Risso's Dolphin
Grampus Griseus ( G. Cuvier, 1812 )




Morphology and dimensions: Delfinide characterised by one relatively high and arch shaped dorsal fin and by a head without rostrum. Measure to birth 1.5 mt., in adult age 3.5 mt. And can reach a weight of 500 - 600 Kg. There are no substantial differences between male and female.

Coloration: Babies are of colour clear grey, which progressively becomes darker with the age. The body of the adult exemplary introduces peculiar white scratches, particularly numerous in older individuals.

Swim and breathing rhythm: The Grampo has a calm swim, but when required can demonstrate remarkable agility. Sometimes it remains in vertical, with the tail outside of the water, for some tens of second. Its immersions can last beyond 20 minutes, while it is assumed to reach remarkable depths.


Feeding: Its diet is substantially constituted by “cephalopods” (several species of squids); the fact is confirmed also by the reduced set of teeth, typical of the “odontoceti teutofagi”.

Social behaviour: It is met in small groups constituted by ten individuals, which sometimes can meet to form consisting branches. The study of the socio-biology of the Grampo, to date not very famous, enters currently in a plan of search lead in Liguria Sea from the Tethys Research Institute.

Vital cycle: The relative data of vital cycle of the Grampo are currently much insufficient and fragmentary, however in progress to be they deepened.

Identification in sea: It can easily be distinguished from other species for the characteristic dorsal fin and the unmistakable coloration. Disseminated in all the Mediterranean Sea, it is more abundant in the western river basin, where it is possible watch it on the bathymetrics between 600 and 1000 meters.