Risso’s dolphin (Grampus griseus)
Family Delphinidae
Description: A large dolphin, measuring up to 4m in length, the Risso’s dolphin dives, you may also notice the deeply incised, serrated tail flukes. The throat is very pale and there is a clear anchor-shaped, white pattern on the belly. When it surfaces close to you, the deep furrow from blowhole to snout along the forehead should be clearly noticeable. Generally a fast moving species that may come up close for a quick look at a boat, snorkeller or diver, before racing away. Although not acrobatic, this dolphin will breach and slam down in the water and often ‘spyhop’, raising its head up to look around and view nearby boats. They also have a habit of rolling over on the surface revealing good views of the diagnostic colour patterns and markings. The scars on the body are mostly teeth marks, a result of some vigorous social interactions within the group.
Habitat: A deep water species, diving for squid and fish over underwater canyons and at the edge of the continental shelf.
Range: Relatively common in the deep water off the coasts of Fujairah and Sharjah, where they may appear in groups of over 30 or they may be in single pairs. They have often been seen with other species, such as sperm whales, false killer whales and bottlenose dolphins.
Comment: From a distance, may be confused with female or young killer whales, which could account for some of the supposed sightings of this species in the UAE. However, the killer whale differs in that it does not have the heavily scarred appearance of the Risso’s, and shows very striking black and white markings, not to mention its much larger size.