Bottlenose Dolphin Facts

Phylum: chordates
Subphylum: vertebrates
Class: mammals
Order: cetacea (toothed whales)
Family: Delphinidae
Species: Tursiops truncatus

The bottlenose dolphin, known by its scientific name as Tursiops truncatus, is the species of dolphin most often found in captive exhibits and swim programs.

General physical characteristics

• Bottlenose dolphins have a sleek, streamlined, aerodynamic shape.

• The pigment of a dolphin's back allows it to blend into its aquatic surroundings. Most fall along a spectrum between gray and blue. The abdomen is white - and can be somewhat pink.

• A blowhole, on the dorsal surface of the head, is the mechanism through which a dolphin breathes. To breathe, a dolphin contracts the muscle flap covering the hole, thus opening it. When the flap is relaxed, the blowhole closes, keeping water from entering the dolphin's system.

• Bottlenose dolphins from the Atlantic Ocean can reach an average of 2.5 to 2.7 m (8.2-8.9 ft.) and weigh between 190 and 260 kg. (419-573 lb.)

• Bottlenose dolphins from the Pacific Ocean can reach 3.7 m (12 ft.), with an average weight of 454 kg. (1,000 lb.). In the Mediterranean, they can grow up to 3.7 m (12 ft.) or more.

• Typically, well-developed males are slightly larger than females and considerably heavier. However, young females grow more quickly than males until they reach the age of 10 years.

Unique Characteristics
The dolphin is considered the most intelligent animal of the aquatic environment, and among the most intelligent animals on the planet.

A dolphin's dominant sense is echolocation. Acoustical "clicks" reverberate back to the dolphin, giving it a very clear picture of its surroundings. Echolocation allows a dolphin to locate food and detect obstacles and other creatures under almost any condition.

Social and Family Structure
Dolphins are very curious, strong and physically resilient. Bottlenose dolphins spend much of their time playing and interacting with their pod members. It is highly sociable and usually sighted in groups of 5, 7 or more. Pods are structured around a matriarchal system.

Distribution
Dolphins frequent bays and coastlines, usually in depths under 20 meters. While some pods take up permanent residence and establish home waters, others are migratory and swim considerable distances from coast to coast.

Threats
Man is the only known enemy of these animals. In particular, the tuna fishing industry has had a profoundly negative effect on the species' survival rates. Since dolphins usually accompany schools of yellow-fin tuna, they are often caught and perish in tuna nets.

Bottlenose dolphins are also hunted as food source, used as shark bait or taken alive to be trained for circus shows in some parts of the world, though there is a growing trend towards protective legislation for dolphins.