Can Moose Swim? How Moose Dive and Feed Underwater

How moose swim

For an animal that can weigh over 600 kg (1,300 lb), a moose is surprisingly at home in water. It swims with its long legs paddling in a steady trotting motion, with its head, the top of its back and, in bulls, the antlers showing above the surface. Its broad hooves spread apart under pressure, which helps it push against the water as well as walk on soft mud.

Several features keep a moose afloat:

• Hollow hair. The long guard hairs of a moose’s coat are hollow and filled with air. They insulate the body in winter and add buoyancy in water.
• A big body. Large animals hold heat well, so moose can spend long periods in cold water.
• Long legs. Moose can wade deep into lakes before they need to swim at all, and their long strides carry them powerfully once they do.

Moose can swim at up to about 9.5 km/h (6 mph), faster than most human swimmers. They can also swim for a long time without resting.

Diving and feeding underwater

Moose are the only deer that regularly feed underwater. In summer they wade into ponds and lakes to eat pondweeds, water lilies and other aquatic plants. Often they simply plunge their head under the surface and lift it up again with a mouthful of dripping plants. In deeper water, a moose may dive completely and has been recorded reaching depths of more than 5 m (16 ft).

A moose’s large, fleshy nose is adapted for this. Fatty pads and muscles close the nostrils when the head is submerged, keeping water out. The moose holds its breath and pulls plants, sometimes roots and all, from the lake bed with its flexible upper lip.

Why go to all this trouble? Water plants are easy to digest and are much richer in sodium than the twigs and leaves of the northern forest. Feeding in ponds in summer helps moose build up this essential mineral. See what do moose eat? for the full seasonal diet.

Long-distance swims

Moose are well known for crossing wide stretches of water. Animal Diversity Web reports swims of up to about 20 km (12 mi). In southeast Alaska, moose are believed to swim across Clarence Strait, about 10 km (6 mi) of open sea, to reach Prince of Wales Island. Moose in Sweden have occasionally swum across the Øresund strait to the Danish island of Zealand, although they did not stay to form a population.

Moose also colonized Isle Royale, an island in Lake Superior about 24 km (15 mi) from the Canadian shore, around the early 1900s, probably by swimming from the mainland or walking across winter ice. The island has since become famous for one of the world’s longest-running studies of predators and prey, following moose and wolves since 1958.

These swims help moose spread into new areas and reach islands and river valleys that other large mammals cannot easily reach. Read more about the moose’s range in where do moose live?

Why moose take to the water

Moose use water for several reasons besides feeding:

Escaping into water is not always safe. Wolves sometimes wait on the shore, and along the Pacific coast of North America orcas have occasionally killed moose swimming between islands, though such kills are rare.

Moose calves in the water

Calves are born in late May or June, often on islands, peninsulas or other spots near water, which may give some protection from predators. Within a few weeks, calves follow their mothers into the water and can swim across rivers and small lakes. In deep or fast water, a calf stays close beside its mother.

Swimming is still risky for young calves. Strong currents and cold water can separate a calf from its mother, and young moose are more vulnerable to predators near the shore.

Watching swimming moose safely

Seeing a moose swim across a calm lake is one of the highlights of a trip to the northern woods. Moose in water still need space: a swimming moose may come ashore near you, and a cow with a calf will defend it. Watch from a distance, never approach a moose in a boat or canoe, and never get between a cow and her calf. More advice on keeping your distance is in are moose dangerous?