Identification at a glance
This species grows to 3.9 m long.
They have:
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- No beak and a broad head
- A tall, often raked, hooked dorsal fin
- Colouration is variable. Dark to pale
- Scarring visible on the sides of many adults and occasionally juveniles
- Long flippers
Range
Risso’s dolphin is widely distributed throughout the world’s temperate and tropical waters, ranging from Newfoundland, the Gulf of Alaska and the North Sea, south towards South America, Southern Africa, Australia and New Zealand.
Risso’s dolphin is also found in a number of partially enclosed waters, including the Red Sea, Gulf of Mexico and Mediterranean Sea.
They appear to migrate northwards during winter, with some individuals sighted as far north as the Gulf of Alaska and the Shetland Islands.
Habitat
Risso’s prefer deep offshore waters, however here in Pembrokeshire we often spot them in shallower coastal areas.
Behaviour
Diet includes squid, crustaceans and cuttlefish.
Fun fact:
Risso’s dolphins are also the only species of cetacean to possess a distinct vertical crease on its forehead.
Threats
Incidental capture in fishing nets, boat strikes, anthropogenic marine noise and pollution including plastic. Like other squid eating marine animals, Risso’s are vulnerable to mistaking plastic for food which can accumulate in the stomach and cause starvation.
Threat Level
IUCN Listing: Least Concern