Odontocetes

Odontocetes, or toothed whales, are a suborder of the Cetacea that includes dolphins, porpoises, beaked whales, belugas, narwhals, and the sperm whale. They are characterized by teeth rather than baleen plates and typically feed on fish, squid, and other marine animals. Odontocetes inhabit oceans worldwide and also occur in some river systems. They range from small porpoises to the large sperm whale and exhibit diverse ecologies and social structures.

A defining feature of odontocetes is their use of echolocation. They emit short, broadband clicks that bounce off objects in the water, allowing them to locate prey and navigate in dim light or turbid conditions. The sounds are focused by a fatty structure called the melon in the forehead. Most odontocetes have a single external blowhole and rely on vocalizations, including clicks and whistles, to communicate within social groups or pods.

Anatomically, odontocetes typically possess teeth arranged along the jaws; the condition varies among species. Some, like beaked whales, have only a few teeth, while others have numerous teeth used for grasping prey. The narwhal’s long tusk, an elongated upper left canine, is a notable exception to the common dentition pattern. Sperm whales have large, robust teeth, and belugas and many dolphins have conical teeth suited to their prey.

Reproduction in odontocetes generally involves long lifespans and extended parental care. Gestation periods span roughly 9 to 17 months, producing a single calf that is nourished by the mother for an extended postnatal period. Calving intervals and growth rates vary by species.

Conservation concerns affect many odontocete species. Threats include historical and ongoing whaling, bycatch, ship strikes, pollution, coastal development, and ocean noise. IUCN statuses range from Least Concern to Endangered, prompting international protection, bycatch mitigation, and habitat conservation efforts.