Bottlenose Dolphin


Common Name: Bottlenose Dolphin

Class: Mammalia

Order: Cetacea

Suborder: Odontoceti

Family: Delphinidae

Genus: Tursiops

Species: Tursiops truncatus



Bottlenose dolphins belong to the Mammalian Order Cetacea, in the suborder Odontoceti.  All toothed whales belong to the suborder Odontoceti, which is Latin for "toothed whales".  This dolphin belongs to the oceanic dolphin family, Delphinidae.  Other members of this family include the killer whale, long-beaked common dolphin, and pilot whale.  The bottlenose dolphin's scientific name is Tursiops truncatus.  The generic name, Tursiops, is derived from the Roman historian Pliny's reference to a dolphin-like fish, tursio.  The suffix ops means "to look like".  The specific name, truncatus, means "shortened or cut-off", referencing this species' stubby rostrum.  The animal's scientific name means "a dolphin like animal with a shortened snout".

This dolphin species is easily identified by its stubby rostrum.  Bottlenose dolphins vary in size throughout their range, reaching lengths from 8-12ft and weighing as much as 1400lbs.  Males are larger than females.  They are gray in color, with a whitish underbelly.  Unlike most oceanic dolphins species, five of the seven neck vertebra of the bottlenose dolphin are not fused.  This gives the animal greater neck flexibility.  A second species of bottlenose dolphin, Tursiops adunctus, inhabits the Indian Ocean alongside this species.


This species' range extends throughout all oceans.  Temperate and tropical waters are preferred.  They are commonly observed living near inlets, harbors and estuaries.  Groups living mainly offshore have also been recorded.  Bottlenose dolphins eat a variety of vertebrate and invertebrate ocean species.  Their diet is composed primarily of fish, but squid and crustaceans are also consumed.


Bottlenose dolphin males form "alliances" with one or two other males.  This small group of males will then kidnap a female dolphin.  Throughout her kidnap, the most dominant male will repeatedly mate with her.  She is eventually released.  The impregnated dolphin bears a single calf after a gestation of 12 months.  The calf will nurse for over a year, remaining with its mother for a total of 3-6 years.  Females reach sexual maturity at 5-10 years of age, with males sexually maturing at 10 years.


Large numbers of bottlenose dolphins still exist.  However, some dangers still threaten this species.  Tuna nets and shrimp trawls can accidentally capture and drown dolphins.  Necessary alterations of these nets now allow dolphins to escape. Other human activities endanger dolphins, such as pollution, habitat encroachment, and human feeding.  Boat collisions are also not uncommon.  A large die off in the late eighties was attributed to the morbillivirus.  Scientists determined that PCB's weakened the dolphins' immune systems, resulting in the contraction of the disease.

Content provided by Canisius College students under the direction of Michael Noonan, PhD.