The ecological niche of the bottlenose dolphin is the role and position the species has in its environment. This includes how it meets its needs for food and shelter, how it survives, how it interacts with the biotic and abiotic factors of its environment.
The habitat of bottlenose dolphins is the surface of temperate and tropical waters worldwide, from coastal waters to the open ocean. The bottlenose dolphin has two ecotypes, the coastal bottlenose dolphin and the offshore bottlenose dolphin. In general, the coastal ecotype is adapted for warm, shallow waters and has a smaller body and larger flippers. These dolphins often live in harbors, bays, lagoons and estuaries.
The offshore ecotype is adapted for cooler, deeper waters and seem to be better suited for deep diving. Its larger body helps conserve heat and defend itself against predators. Variations in water temperature, movements of food (mainly fish), and feeding habits may account for the seasonal movements of some dolphins to and from certain areas. Bottlenose dolphins may hunt in pods as small as 2 dolphins to pods as large as hundreds of dolphins. However, pods of 2 to 24 dolphins are most common.
Bottlenose dolphins eat a variety fish, squid and crustaceans. An adult dolphin may eat 15 to 30 pounds of food a day. Humans are the largest predators of bottlenose dolphin. Bottlenose dolphins reside at the near top of the food chain and are only eaten by some of the larger and more aggressive shark species, including great white sharks, tiger sharks and bull sharks. Dolphins consider sharks a natural enemy and often attack sharks by ramming them in the gills. Bottlenose dolphins are also, though infrequently, eaten by orcas.