Is narwhal a whale?

Quick Answer

Yes, the narwhal (Monodon monoceros) is absolutely a whale. Specifically, it is a toothed whale belonging to the suborder Odontoceti within the order Cetacea — the same order that includes every whale, dolphin, and porpoise on Earth. Narwhals are medium-sized whales that can reach up to 5 meters in length and 1,600 kilograms in weight. Often called the “unicorn of the sea,” the narwhal is one of only two living species in the family Monodontidae, sharing that family exclusively with the beluga whale. Their classification as whales is well-established and not a matter of scientific debate.

What You Need to Know

Where Narwhals Fit in the Whale Family Tree

Understanding why a narwhal is a whale requires a brief look at cetacean taxonomy. All whales, dolphins, and porpoises belong to the order Cetacea, which is divided into two main suborders:

• Mysticeti (baleen whales) — filter-feeders like the blue whale and humpback whale that use baleen plates to strain food from seawater.
• Odontoceti (toothed whales) — predators with teeth, including sperm whales, beaked whales, dolphins, porpoises, and narwhals.

Narwhals fall squarely into the Odontoceti suborder. Within that group, they belong to the family Monodontidae, a small family containing just two species: the narwhal and the beluga whale. Both are Arctic-adapted, medium-sized whales with rounded heads and no dorsal fin. Genetic evidence confirms that narwhals and belugas diverged from a common ancestor roughly 5 million years ago, making them each other’s closest living relative.

So while narwhals may look unusual compared to the massive baleen whales many people picture when they hear the word “whale,” they share all the defining characteristics of cetaceans and are classified as whales by every major scientific and conservation body, including NOAA and the International Whaling Commission.

What Makes a Narwhal a Whale (and a Mammal)

Like all whales, narwhals are marine mammals, not fish. They share the core traits that define every cetacean — and indeed every whale. If you’re curious about why whales are mammals in the first place, our article on are whales mammals covers the topic in depth. Here are the key features narwhals share with all other whales:

• They breathe air. Narwhals surface to breathe through a blowhole on top of their heads. They can hold their breath for remarkably long dives, reaching depths of 800 to 1,500 meters when hunting.
• They are warm-blooded. Narwhals maintain a constant body temperature despite living in frigid Arctic waters year-round, insulated by a thick layer of blubber.
• They nurse their young. Female narwhals give birth to live calves and nurse them with milk, a hallmark of all mammals. Calves stay with their mothers for over a year.
• They have vestigial limb structures. Like other whales, narwhals possess small pelvic bones — evolutionary remnants from their terrestrial ancestors, a fascinating piece of whale evolution.

The Tusk: A Whale Tooth Like No Other

The feature that makes narwhals so distinctive — and perhaps fuels the confusion about what they are — is the tusk. This long, spiraling projection is not a horn. It is actually an enlarged upper left canine tooth that erupts through the lip and can grow up to 10 feet (about 3 meters) long. Most tusked narwhals are male, though roughly 15% of females also develop a shorter tusk.

The tusk contains millions of nerve endings, and scientists believe it functions as a sensory organ capable of detecting changes in water temperature, salinity, and pressure. Some researchers have also observed narwhals using their tusks to stun fish before eating them. This remarkable anatomy is unique among whales, but it is fundamentally a modified tooth — reinforcing the narwhal’s identity as a toothed whale.

How Narwhals Compare to Other Whales

It can be helpful to see where narwhals sit relative to other well-known whale species in terms of size and weight:

• Narwhal: Up to 5 m long, 1,600 kg — a medium-sized toothed whale.
• Beluga whale: Up to 5.5 m long, 1,600 kg — the narwhal’s closest relative and very similar in size.
• Sperm whale: Up to 18 m long, 57,000 kg — the largest toothed whale.
• Blue whale: Up to 30 m long, 150,000 kg — the largest animal ever, and a baleen whale.

Despite their modest size compared to the ocean giants, narwhals are unquestionably whales. The question are dolphins whales explores similar classification nuances — dolphins are technically toothed whales too, though common language often separates them.

Where Narwhals Live

Narwhals are among the most geographically restricted whale species. They live exclusively in Arctic waters, primarily in the Atlantic sector of the Arctic Ocean around Canada, Greenland, Norway, and Russia. Unlike many whale species that undertake long seasonal migrations to warmer waters, narwhals spend their entire lives in the Arctic, moving between coastal summering grounds and deeper offshore waters in winter. For more on their range and habitat, see our guide on where narwhal whales live.

Their remote, ice-covered habitat is one reason narwhals remain among the least studied whales. An estimated 80,000 narwhals exist in the wild, and the species is currently listed as Least Concern by the IUCN, though climate change and shifting sea ice patterns pose growing threats. Learn more about their outlook in are narwhal whales endangered.

Key Takeaways

• Narwhals are whales. They are toothed whales (odontocetes) in the family Monodontidae, closely related to beluga whales.
• They share all defining whale traits: air-breathing, warm-blooded, live birth, nursing, and a fully aquatic lifestyle.
• The tusk is a tooth, not a horn. It can reach 10 feet in length and functions as a sensory organ — a feature unique among cetaceans.
• Narwhals are medium-sized whales, growing up to 5 meters and 1,600 kg, comparable in size to belugas.
• They live only in the Arctic, making them one of the most range-restricted and least observed whale species on the planet.
• Their conservation status is Least Concern, but Arctic warming and ice loss are emerging threats that could affect their long-term survival. Read more about whale conservation efforts worldwide.