Land Mammals

With 112 species of mammals in the state, Alaska has a high level of mammalian diversity and the Seward Peninsula is no exception. Ranging from the smallest shrews weighing just 5 grams to brown bears over 1,200lbs and sea mammals even larger, such as the 200,000 lb bowhead whale, the state offers some of the most spectacular wildlife viewing in the US. Check out some of the most common species you'll see in Bering Land Bridge National Preserve, below!

A large adult muskox lumbers through a patch of green willows
A muskox saunters through the willows

NPS Photo - Jason Gablaski

Muskox (Ovibos moschatus)

Muskoxen are an iconic herbivore of the Seward Peninsula and Bering Land Bridge National Preserve. Most muskoxen live in Greenland and Arctic Canada, although smaller populations inhabit Alaska, Siberia, and Norway.

As bovines, they are more closely related to cattle, sheep and goats than to oxen. Both males and females sport fabulous curved horns, although the males' horns are much larger for use in fights and for personal defense. In addition, they are also known to protectively circle their young, when threatened, or charge at their offenders.

With a relatively low reproductive rate, muskoxen give birth to only one calf every 2-3 years in late April or May. By adulthood, they can weigh anywhere from 400-800lbs. Although their populations have fluctuated over the last century, dropping to just over 100 individuals in 1980, today they number around 3,800 in the state of Alaska.

A beaver lodge sits in the middle of a pond created by a large dam
A beaver lodge can be seen in the middle of a pond created by a large dam

NPS Photo - Andrea Willingham

North American Beaver (Castor canadensis)

More industrious than any other mammal besides humans, and larger than any other rodent in the United States, the North American beaver is becoming increasingly abundant in Bering Land Bridge National Preserve. With large webbed feet and a broad, scaly tail, these semi-aquatic mammals range in size from 2-3 feet long with about a 1 foot long tail and can weigh up to 60 lbs. A second set of transparent eyelids allows them to navigate underwater for up to 15 minutes at a time.

Beavers live in colonies of 2-12 individuals (usually related family groups) and are known for creating extensive dams and lodges that can totally alter entire stream systems and waterways. Using their continually growing front incisors to gnaw down trees, they build these structures primarily for protection against predators and to provide easier access to food during the winter. As nocturnal herbivores, their diets consist entirely of vegetation, such as leaves, bark, twigs, and roots, and will stash their food underwater to access it during winter months.

Historically, beavers have been one of the most commonly trapped mammals for their fur, to the point where they were eliminated from most of their range in the 1800s. Now that trapping is regulated their population remains around 6-12 million, though a far cry from the estimated 60 million that once inhabited the continent.

A red fox looks out from near its den on the late spring snow cover.
A red fox guards its den on the late spring snow.

NPS Photo - Allyce Andrew

Red Fox (Vulpus vulpus)

The red fox is common in North America and found all throughout Alaska. Preferring lowland marshes, it is most common south of the arctic tundra although it will occasionally share tundra habitat with its relative, the arctic fox (Vulpus lagopus). Classified in the canine family, red foxes are approximately 2 feet long with about a 1 foot long tail, and can weigh anywhere from 6-15lbs.

With its reddish coat, dark feet and legs, and white-tipped tail, the red fox can be distinguished from the arctic fox, which is grey or white depending on the season. It is primarily because of their beautiful fur that red foxes have been hunted since as far back as the 4th century BC. Today they are still commonly hunted and trapped for the fur trade, as well as for pest control by agriculturalists.

Although mostly carnivorous, red foxes will eat a variety of small mammals, birds, eggs, insects, carrion, and vegetation. They are known to stash their food, and mark their territory with their scent glands, with a distinctively skunk-like odor.

A large grizzly bear lumbers across the tundra
A large brown bear lumbers across the tundra

NPS Photo

Brown Bear (Ursus arctos horribilis)

With the average male standing up to 7 feet tall and weighing 400-800lbs, the brown bear is one of the largest mammals that makes its home in Bering Land Bridge National Preserve. As omnivores, they are known to prey on fish, elk, moose, and caribou, but about 85% of their diet consists of vegetation and insects. In preparation for their 5-8 month hibernation period, brown bears can gain up to 400lbs in the fall.

Although typically solitary, females can be seen with anywhere from 1-4 cubs that will stay with their mother for up to 2 years. With one of the lowest reproductive rates of any terrestrial mammal in North America, brown bears are vulnerable to a wide variety of ecological issues, including habitat loss and fragmentation, and climate change.

Brown bears are not typically aggressive, unless they feel threatened or startled. To avoid conflict with bears, talk loudly while hiking, hike in open areas away from dense vegetation, and avoid approaching a grizzly if you see one. It is a good practice to keep all food and toiletries at least 100 feet away from camp in bear proof containers when camping in the backcountry. Read more about bear safety here.

A large herd of reindeer stands on a sunny beach
A reindeer herd gathers on the beach

NPS Photo - Andrea Willingham

Caribou & Reindeer (Rangifer tarandus)

Caribou and reindeer are almost identical, sharing the same genus and species name. It wasn't until about 2,000 years ago that they were domesticated in Eurasia became what we know as the modern day reindeer.

Originally, caribou natively populated Alaska long before reindeer were introduced from Siberia by a missionary in 1892. Over a period of about 60 years, Inupiat communities were trained to herd them, through apprenticeship programs. After reaching peak popularity in the 1930s, the practice of reindeer herding has since declined, and today all reindeer on the Seward Peninsula are managed by about 20 herders. The free-ranging herds can occasionally be seen grazing in the coastal areas of the preserve, or throughout the tundra near the villages.

Although they look almost identical, caribou can be identified by having longer legs and leaner bodies than reindeer. Reindeer are typically more sedentary, have thicker fur, and some may have white or patchy markings.

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Mailing Address:

P.O. Box 220

Nome, AK 99762


(800) 471-2352
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