Striped dolphin
(Stenella coeruleoalba)
Striped dolphins live in groups of a dozen to 500 or more animals. They are sometimes encountered in the company of common dolphins or spotted dolphins. They are striking animals already admired by the ancient Greeks who painted them on frescos at Mycenae.
General information
Further names: Portuguese: Golfinho-riscado
Size of adults: 1.8 – 2.5 m
Prey: Fish, cephalopods and crustaceans.
Behaviour: Very active at the surface, often executing acrobatic leaps with synchronised group behaviour. Off Madeira, they are relatively shy and only approach boats in the company of other, more interactive dolphin species.
Range: Striped dolphins occur globally in warm temperate and tropical waters. Usually prefer waters far away from the coast. There is scientific evidence stating that they migrate seasonally, following warm-water currents.
Madeira: Occur all year round, usually further off the coast when common dolphins or spotted dolphins are close by.
Distinctive features: Slender body with stripes of different colours between the eyes and the fluke. Two stripes are especially visible: one extends from the eyes to the lower abdomen and the other, smaller stripe from the eyes to the root of the flippers. They are coloured dark dorsally with a pale belly and a grey patch extending over the fluke. Their forehead meets their beak at a sharp angle. Striped dolphins are thought to live for more than 40 years and only reach sexual maturity at around 8 to 10 years of age.
Taxonomy: Suborder: Odontoceti (Toothed whales), Family: Delphinidae (Dolphins)
Threats: Listed as not threatened. The estimated population size is about 2 million individuals world-wide. Populations may however be locally threatened; in the Mediterranean their numbers have dropped drastically due to collisions with boat propellers and drowning in illegal drift-nets. Striped dolphins are still slaughtered in Japan along with several other dolphin species.