Bottlenose Dolphin -- Cetacean Info at Whale Songs

SCIENTIFIC NAME: Tursiops truncatas

COMMON NAME: Bottlenose Dolphin


* Found largely in coastal waters between 45N and 45S, and also in Northern European waters.


* Size: Adults from 1.9 to 3.8m, weighing up to 650kg. There is tremendous variation between populations, as different groups, known as ecotypes, are adapted to the different conditions in which they live.



* Coastal and Oceanic species
* Populations generally occur in water in less than 30 miles from shore
* Found in open coasts with strong surf to sheltered bays and waterways, lagoons, large estuaries and the lower reaches of rivers


* Their feeding behaviour is extremely varied, depending on what is available. They may co-operate to forage on large schools of fish, or chase individual fish inshore. They have also been seen feeding behind trawlers and other fishing boats. This adaptability in feeding has undoubtedly contributed to their success, and enabled them to range so extensively.


* Life Span: 30+ years
* Gestation period: 12 months
* Peak seasons for mating: May and June
* Calving interval: two to three years
* Nursing lasts: calves suckle for up to 18 months
* Sexual maturity begins at 9-10 for males and 10-13 years for females


* Bottlenose Dolphins live in fairly open groups, generally containing no more than 20 animals, but large herds have been seen offshore.
* They commonly associate with other dolphin species, and sometimes they may interbreed.


* Total worldwide population unknown
* 10,000-13,000 off northeastern United States
* 40,000 in Gulf of Mexico
* 35,000 in western North Pacific and Japanese coastal area
* less than 10,000 in Mediterranean
* 250 off Indian Ocean coast of South Africa south of Natal
* less than 1,000 in north of Natal


* Bottlenose dolphins are taken incidentally and directly.
* The largest direct expliotation has been in the Black Sea, but they are occasional victims of harpoon and drive fisheries in many places.
* They are known to suffer from gillnets, shark nets, shrimp trawls and purse seine nets in the eastern Pacific tropical tuna fishery.
* There is current controversy in the US senate about the import ban on tuna caught with large dolphin by-catch - this is something you may wish to find out more about.
* Live-capture removals (the taking of dolphins for keeping in captivity have had large effects on populations of bottlenose in the Gulf of Mexico and the U.S. southeast coast.