Illustrations by

© M.Würtz/Artescienza.org

Risso’s dolphin

Grampus griseus

Risso’s dolphin | Grampo

The Risso's Dolphin is a species that lives in small groups of 5-10 specimens on average. It prefers waters along the continental escarpment, between 500-1000 m of depth.

Features: at the birth the livery is grey, but growing up, it is covered by numerous scars which, with increasing age, cover the whole body till when it assumes a white colouration, in particular in the part of the head. The head is bulbous with a V-shaped groove in the centre, and ends with a very small rostrum. It is endowed with 2-7 teeth present only in the lower jaw which serve only to hold the food. The dorsal fin is high and falcate and also recognizable by the presence of scars and scratches, which allow to identify each specimen.

Max Lenght: 4 m

Max Weight: 500-600 kg

Longevity: around 40yrs

Dive Time: 1-10 min

Dive Depth: – 300 m; max ever recorded – 460 m.

Velocità massima: 30 km/h (ma in generale predilige un nuoto lento 7 km/h)

Food Diet: mainly cephalopods

Classificazione IUCN-Red list: LC (Least concern ). DD (Data Deficient. Mediterranean population)

Threats: noise pollution, intensive fishing.

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