Pilot whale: It is morphologically very similar to the tropical pilot whale, but it differs in the gray color of its skin (almost white in some adult specimens) and the contrast with the dorsal fin, which is still dark. Weight: 300-600 kg.
Grampus griseus, also known as the Risso’s dolphin, is a species of dolphin found in deep, temperate waters around the world. It is a member of the family Delphinidae and is one of the largest dolphins, measuring up to 4 metres in length and weighing up to 600 kg.
The Risso’s dolphin is dark grey on top and white or light grey underneath. It has a large, bulbous head with a distinctive dorsal crest extending from the back of the head to the base of the dorsal fin. The dolphin also has a long, narrow beak with sharp teeth.
These dolphins are highly social and are often found in groups that can range from a few individuals to more than 50. They are known for their acrobatic behaviour and are often seen leaping and spinning in the air.
Risso’s dolphins feed mainly on squid and deep-sea fish, and are very effective predators in the water. However, like many other cetacean species, it is threatened by bycatch, pollution and habitat disturbance.
Although hunted in the past for their meat and oil, this practice has greatly diminished today. However, the species is still considered “near threatened” by the International Union for Conservation of Nature (IUCN) due to a lack of population data and continuing threats to its habitat and survival.