Monodon

Monodon is a small genus of toothed whales in the family Monodontidae, best known for Monodon monoceros, the narwhal. The genus name and the species epithet derive from Greek roots meaning “one tooth” and “one horn,” referring to the narwhal’s distinctive tusk. The narwhal is the only extant species in Monodon, though extinct relatives have been described in scientific records.

Narwhals are medium-sized Arctic cetaceans. Adults generally measure about 4 to 5 meters in length and weigh roughly 800 to 1,600 kilograms. A defining feature is the long, spiral tusk found most often in males, which is an elongated canine tooth that can reach several meters. Females may have shorter or less prominent tusks. The body coloration is predominantly gray with varying pale patches, and individuals can show little to substantial color variation with age.

Distribution and habitat are Arctic and sub-Arctic, including waters around Greenland, Canada, and parts of Russia and Norway. Narwhals rely on sea ice and coastal inlets, migrating seasonally between wintering grounds under the ice and summering areas in deeper, ice-free zones. They typically form social groups ranging from tens to a few hundred individuals.

Diet consists mainly of fish, such as Greenland halibut and cod, as well as squid and crustaceans. They hunt by using echolocation to detect prey under the ice and in open water.

Reproduction occurs with long intervals between calves. Gestation lasts about 14 to 15 months, and calves are born at roughly 1 meter in length. Narwhals may live several decades, often 30 to 50 years in the wild.

Conservation status is Near Threatened on the IUCN Red List, with ongoing concerns including climate change impacts on sea ice, subsistence hunting by Indigenous peoples, and disturbances from shipping and industrial activities.