Delphinidae Family of Dolphins

Seven Dolphins of the Delphinidae Family can be found in this website:

Phylogeny: Oceanic Dolphins are members of the largest family of Cetaceans, the Delphinidae Family. They belong to the phylum Chordata, the class Mammalia, and the order Artiodactyla, which is the same order as the hoofed ungulates, from which they evolved. They are in the infraorder Cetacea which contains two superfamilies- Mysticeti  (baleen whales), and Odontoceti (dolphins and toothed whales). Dephinidae is one of seven families in the superfamily Odontoceti. The Delphinidae Family is comprised of four subfamilies, eighteen genera, and thirty-eight species.

Morphology:  All Oceanic Dolphins have a single blowhole on top of their head, just to the left of center. Dolphins differ from porpoises by having pronounced beaks and more conical, sharper, teeth, with a cutting edge. They all have a dorsal fin located in the center of their back, and a notch in the center of the trailing edge of their fluke (tail). Oceanic Dolphins vary greatly in coloration, body shape, beak length, beak width and social habits. They range in size from 1.7 m (5 feet 7 inches) to 9.0 m (29 feet 6 inches) in length.

Distribution:  Not all members of the Delphinidae Family live in the ocean as some live in lakes or rivers. Oceanic Dolphins are found in open water, in bays, harbors, coastal waters, and the open ocean. As air breathing mammals they need to come to the surface to breath and will often rest at the surface, but all species need to dive to hunt. Members of this family can reach depths up to 4,725 m (15,500 feet). Oceanic Dolphins are found globally in all polar to tropical seas. At least sixteen members of this family are found in Mexican waters.

Reproduction: As mammals, Oceanic Dolphins are gonochoric (male or female for life) and reproduce sexually with internal fertilization. Females give birth to a single calf after a ten to eighteen month gestation period. The calves will nurse for two or more years.

Ecosystem Roles:  All Oceanic Dolphins are predators that feed on free swimming fish, squid, and other marine mammals. Some also eat benthic prey such as algae, octopus, shrimp, tunicates, and worms. In turn Oceanic Dolphins are preyed upon by sharks and other Oceanic Dolphins including Killer Whales and False Killer Whales.