By Tyler Carter, Golden Cole, Rich Leeson

Bottlenose dolphins are the most familiar of all dolphins due to television shows, books, and children’s programs. The bottlenose dolphin can reach a length of 13 feet and a weight of 1430 pounds. The male bottlenose dolphin is generally larger than the female bottlenose. With regard to various subspecies, races, variations, and discrete geographical populations, there exists a taxonomic tangle of enormous complexity. This controversy dates all the way back to 1889 when F. W. True listed no fewer than four "valid" species in his book Review of the Delphinidae. The four species he listed was Tursiops tursio, Tursiops catalania, Tursiops abusalam, and Tursiops gillii. True also said that the Tursiops aduncus "may or may not prove to be distinct."

In recent works the Tursiops aduncus, Tursiops gillii, Tursiops nuuanu, and Tursiops truncatus are recommended for specific status. Other authors hold that there is only one worldwide geographical race varying in color, tooth count, and body size. Conservative taxonomists recognize a single species of bottlenose dolphin, Tursiops truncatus truncatus.

Bottlenose dolphins are generally an inshore species that is rarely found more than 500 miles out to sea. They have 23 to 25 pairs of sharp, sturdy teeth in each jaw. The bottlenose dolphin also has great mobility in the region of the neck. The reason for this great flexibility is due to the fact that 5 of the 7 vertebrae are unfused. In other dolphins all 7 of the cervical vertebrae are fused.

Conservative taxonomists also recognize the following subspecies, differentiated by geography and morphology. The Tursiops aduncas is a darker gray on the dorsal side, white on the ventral side, with grayish spots incorporated into the white. The Tursiops aduncas is found in Australian waters, the Indian Ocean, and the South China Sea.

Not much information is found on the Tursiops gephyreus. It is found near Argentina and near the South American Pacific coast. The Truncatus abusalam is found in the Red Sea, off the coast of Saudi Arabia, and near Egypt.

The Tursiops truncatus is bluish, steel gray, with a dark stripe from the blowhole to the base of the beak. It is found in the Atlantic Ocean, the East Coast of the United States, and some are found on the European Atlantic Coast.

The Tursiops gillii is basic gray, with a dark dorsal fin, and a black stripe from the eye forward. The gillii is found in the Pacific Ocean, and the North Pacific near Japan.

The Tursiops nuuanu are lighter gray, with a slightly lighter whitish-gray stripe behind the pectoral fin. The nuuanu are found in the Pacific, and the Tropical Pacific near Panama. Two of the major differences between bottlenose dolphins are that the dental structures and the vertebral columns. We came to the conclusion that bottlenose dolphins should be a single species with different subspecies.

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