Scientific Name: Grampus griseus
Malti: Id-denfil ta’ Risso
The Risso’s Dolphin (Grampus griseus) is one of the largest species of dolphin, growing up to 3.8 metres in length and weighing up to 500kg. They are easily identified by their dark grey colour with extensive white scarring (this scarring is an identifying features for recognising this species, as is the lack of a ‘bottlenose’); the scars are usually scratches or circular marks caused by bites from other Risso’s dolphins, squid bites, or parasites. In some animals, the scarring can be so extensive that the entire body appears to be white. Their dorsal fin is tall, slightly curved and located near the middle of the back. The flukes are broad and curved with a deep median notch and they have long thin flippers.
The typical size of a Risso’s dolphin pod is between 3-30 animals, although “super-pods” of up to several thousand together have been observed, it is also very common for Risso’s dolphins to form travelling pods at sea with other dolphin species. Risso’s dolphins tend to prefer offshore habitats throughout the warm temperate and tropical waters of both hemispheres.
They primarily prey on squid, but have also been known to feed on a number of fish species and they are a fairly active species, often leaping, spy hopping, fluke slapping, and flipper slapping, but do not usually approach boats unlike other dolphin species which like to surf bow waves.
Formerly Risso’s dolphin was thought to be rare, probably cause by their offshore distribution, however exact numbers are still not known. Risso’s dolphin, along with all other cetaceans species present in this area, is also covered by the Agreement on the Conservation of Cetaceans in the Black Sea, Mediterranean Sea and Contiguous Atlantic Area (ACCOBAMS), amongst others. This agreement aims to reduce threats to cetaceans in Mediterranean and
Black Sea waters and improve our knowledge of these animals.