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  • Stenella longirostri

    Common Name: Spinner Dolphin

    Stenella spp.: Based on recent genetic studies the genus Stenella will mostly be restructured in the near future.

    General Description: Spinner dolphins are slender with a long thin beak and pointed flippers. Head slopes gently towards the snout. Dorsal fin is falcate but highly variable in shape, and becomes more erect with age. Most individuals have a tripartite colour pattern with a dark grey back and white underbelly and the sides a paler shade of grey. Individual variation in colouration can be seen. Most individuals have a dark stripe extending from the eye to the flipper. Beak tip and lips are dark.

    Spinner dolphin in Andaman islands @ Mahi Mankeshwar

    Size: Adults, around 2 m long (males:2.35m). Males maybe larger than females, most adults weigh around 75-80 kg. Calves at birth, 75-80cm long.

    Appearance At Sea: The Spinner Dolphin gets its name from its habit of leaping out of the water and spinning longitudinally. Individuals have been counted rolling over seven times before falling back into the water. They are known to bow-ride. Group sizes can range from 30 to several hundreds. They are known to sometimes associate with other dolphin species (e.g. Stenella attenuata; spotted dolphins). Spinner dolphins are frequently found in association with tuna, this can result in entanglement in purse seines.

    Found In: The Spinner Dolphin’s distribution is primarily in pelagic zones, though it will wander into shelf waters. They feed on small fish and squid.

    Records from India:This is a species caught frequently by fisheries by-catch . 

    Date : Prior to 1827
    Details : Photograph of skull (illustration) from Malabar in the US National Museum files.
    References : De Silva, 1987

    Date : 1976–1980
    Details : Ninety-two specimens caught in gillnets off the Calicut coast.
    References : Lal Mohan, 1985

    Date : 19 September 1981
    Details : Male specimen caught in gillnet off Calicut.
    References : James & Lal Mohan, 1987

    Date : 1982­–1984
    Details : SA number of observations off the coasts of southern India.
    References : Alling, 1986

    Date : 15 May 1982
    Details : One specimen collected at Porto Novo (11º29’N; 79º46’E) in a bottom-set gillnet.
    References : Rajaguru & Natarajan, 1985;
    Kumaran & Subramanian,1993

    Date : July 1983­–December 1986
    Details : 18,210 kg of this dolphin landed at Fisheries Harbour, Cochin.
    References : Jayaprakash et al., 1995

    Date : 11 February 1986
    Details : One male, 1.9 m long, caught at Bombay High near the ONGC offshore base in a gillnet.
    References : Karbhari et al., 1985

    Date : 5 March 1986
    Details : One male, 2.28 m long, caught off Janjira–Murud, Maharashtra in gillnet.
    References : Karbhari et al., 1985

    Date : 29 August 1989
    Details : One specimen caught in a gillnet in the Gulf of Mannar.
    References : Krishna Pillai, Bose et al., 1989

    Date : 28 December 1990
    Details : Nearly 300 counted at sea, south of Mangalore at 11°46’N, 10°E.
    References : Jayaprakash et al., 1995

    Date : 2 1 August 1991
    Details : One young female entangled in gillnet off Visakhapatnam – this was only 70.5 cm long & 2.66 kg in weight .
    References : Seshagiri Rao & Narayana Rao, 1992

    Date : 1993 [?]
    Details : Two animals entangled in gillnets at the Calicut coast.
    References : Lal Mohan, 1995

    Global Distribution: The species is widely distributed. It is found in all oceans, in tropical, subtropical and warm temperate regions.

    Could Be Confused With:The Spinner Dolphin could be confused with the Common Dolphin Delphinus delphis which has a very similar body shape. They can be distinguished based on the following characteristics:

    Species : Spinner Dolphin
    Fin : Upright or leaning forwards
    Markings :

    • Tripartite colour pattern
    • Dark stripe from the eye to the flipper;
    • Dark lips and beak tip

    Species : Common Dolphin
    Fin : Fin leaning backwards
    Markings :

    • Hourglass pattern of yellow on side;
    • Dark stripe from flipper to chin

    Diagnostic Features: At sea, tripartite colour pattern, spinning behaviour, and dark-tipped beak.

    Stranded Specimens:Spinner Dolphins have 45 to 65 or more sharply pointed teeth in each row. This is the highest tooth-count of any cetacean species.

    Spinner Dolphin

    Dolphin skipping on its tail over the water.

    Size comparison against an average human

    Conservation Status

    Least Concern (IUCN 3.1)

    Scientific Classification

    Kingdom Animalia
    Phylum Chordata
    Class Mammalia
    Subclass Eutheria
    Order Cetacea
    Suborder Odontoceti
    Family Delphinidae
    Genus Stenella
    Species S. longirostris

    Binomial Name

    Stenella longirostris

    ( Gray, 1828 )

    Pantropical Spotted Dolphin range.

    Source: Wikipedia