Lagenodelphis hosei

Description

This tropical dolphin was scientifically described in 1956 from an individual washed up on a beach in Borneo, but was not actually recorded alive until the 1970s. Fraser's dolphin can be identified by its stocky body and short beak, and by its small flippers, tail fin and triangular or slightly curved dorsal fin. The body bears a striking colour pattern, but one that varies with both age and sex. The back is brownish-grey, the lower sides of the body cream-coloured, and the belly is white or pink. A prominent black stripe runs along the side of the body from the eye to the anus; in adult males this is thick, while in adult females it is variable and in young dolphins the stripe is faint or completely absent. The same pattern occurs with a black stripe on the face; this is absent in calves and variable in females, while on adult males it is extensive and merges with the body stripe to form a 'bandit mask'.

Geography

Azores Exclusive Economic Zone, Comores, European waters (ERMS scope), Gulf of Mexico, Kenya, Madagascar, Mauritius, Mediterranean Sea, Mozambique, North West Atlantic, Pacific Ocean, Portugese Exclusive Economic Zone, Reunion, Seychelles, Somalia, Spanish Exclusive Economic Zone, Tanzania 

Ecosystem

It is an oceanic species that prefers deep offshore waters, but it can be seen near shore in some areas where deep water approaches the coast (such as the Philippines, Taiwan, and some islands of the Caribbean and the Indo-Malay archipelago) (Perrin et al. 1994).

In the eastern tropical Pacific, it occurs more often in Equatorial - southern subtropical surface water and other waters typified by upwelling and generally more variable conditions (Au and Perryman 1985). Off South Africa, records are associated with the warm Agulhas Current that moves south in the summer (Perrin et al. 1994).

Fraser's dolphins feed on midwater fish (especially myctophids), squid, and crustaceans (Dolar et al. 2003). Physiological studies indicate that Fraser’s are capable of quite deep diving (and it is thought that they do most of their feeding deep in the water column – in waters up to 600 m deep), but they have been observed to feed near the surface as well (Watkins et al. 1994).

Conservation

The species is widespread and abundant (with current population estimates around 300,000) and there have been no reported population declines or major threats identified.

Threats