How to Identify Bison in North Dakota

Bison are the largest land mammals in North America, and they are unmistakable once you see one. Adult bison stand 5.5 to 6.5 feet tall at the shoulder and weigh between 900 and 2,000 pounds depending on sex and age. The most obvious feature is the massive hump over the shoulders and front legs, made up of muscle and a thick body. Their coat is dark brown or black, often appearing almost black in strong sunlight or from a distance. The hair on the head, neck, and front legs is particularly thick and shaggy, giving them a powerful, imposing silhouette. Both males and females have curved horns that point inward and slightly upward, though males typically have thicker, shorter horns than females. Their tail is short and ends in a tuft of hair, which they raise when alarmed. The front half of a bison is massive and muscular, while the hindquarters are smaller and appear almost tapered by comparison.

At first glance, bison and cattle might seem similar because both are large hoofed grazing animals, but several clear differences set them apart. Bison have a much more pronounced hump over the shoulders and front body, while cattle have a level back. Bison heads are enormous and broad, carried low, whereas cattle have smaller, more refined heads held higher. Bison horns curve upward and inward, while cattle horns vary by breed but often point sideways or downward. The shaggy, thick coat of a bison is immediately recognizable, especially on the head, neck, and front legs, giving them a wild appearance cattle lack. Bison are also much heavier and more robustly built overall, with thicker legs and a more barrel-shaped body. If you encounter a large brown or black animal in North Dakota grasslands or a refuge area, the hump and massive head are the quickest identifiers of a bison versus any breed of cattle.

Bison are predominantly dark brown to black, with the darkest coloring often on the head, neck, shoulders, and front legs where the hair is thickest and longest. Some individuals appear nearly jet black, especially in strong sunlight or at certain angles. During spring and early summer, bison shed their thick winter coat in large patches, which can make them look patchier or even lighter temporarily as the shorter summer coat grows in underneath. By mid-summer, the coat has typically fully transitioned, becoming slightly shorter and sometimes appearing a bit lighter brown than the dense winter coat. By fall, they begin growing their thick winter coat again, restoring the full, dark appearance. This shedding pattern means that a bison viewed in early summer might look somewhat different than the same animal in midwinter, but the core coloring remains dark brown to black year-round. The hump and body shape remain consistent and are more reliable identifiers than coat color alone.

There is one species of bison in North America, Bison bison, found in North Dakota today. However, bison can be classified into two subspecies: the plains bison and the wood bison. North Dakota's herds are plains bison, the subspecies that historically roamed the Great Plains grasslands and prairies where the state is located. Plains bison are well adapted to open grasslands, and the herds maintained in North Dakota's state parks, federal refuges, and tribal lands are all plains bison. You will not encounter wood bison in North Dakota, as they are found in the northern boreal forests of Canada and are not part of North Dakota's wildlife or conservation efforts. When you see a bison in North Dakota, you are looking at a plains bison, the animal that shaped the prairie ecosystem and remains a living link to the state's natural heritage.

From a distance, the key feature is the profile: the high, rounded shoulder hump that rises well above the level of the hindquarters is visible from hundreds of yards away and is your strongest clue. This hump is so distinctive that even a silhouette against the sky makes a bison recognizable as bison and not cattle. The massive, broad head held low is another strong distance clue, especially if you see the head in profile. If the animal is moving, bison have a characteristic lumbering gait that differs from the more delicate, bouncy movements of elk or deer. The overall body mass and solidity are also apparent from afar; bison fill more space than cattle and appear more densely muscular. In North Dakota's western grasslands and refuge areas, any very large, dark, heavily built animal with a prominent shoulder hump and broad head is almost certainly a bison. Binoculars will reveal the hump, horns, and massive head clearly from safe viewing distances.

Bison have split hooves (called cloven hooves) that are dark and roughly heart-shaped when viewed from above. Each hoof is about 4 to 5 inches long and wide, making bison tracks substantially larger than cattle tracks. In mud or snow, a bison track shows a clear split down the middle, and the overall print is deep and wide due to the animal's enormous weight. A single bison track in soft ground can be several inches deep. Bison tracks are often accompanied by a trail of disturbed earth and vegetation from the animal's heavy body pressing through the landscape. If you find fresh tracks in North Dakota grasslands or near refuge areas, the size (much larger than deer or elk) and the cloven hoof pattern confirm they belong to a bison. Tracking is useful in winter when snow and mud reveal recent movement patterns of herds in places like Theodore Roosevelt National Park or federal wildlife refuges.

Bison are generally quiet animals, but they do vocalize when alarmed, during mating season, or in social situations. Bulls produce low, guttural grunts and bellows that carry across the prairie, especially during rut in July and August. Cows and calves make lower-pitched moos and grunts for communication, and a startled or agitated bison may snort loudly as a warning. Calves can bleat when separated from mothers, producing a sound similar to a domestic cow calf. The most dramatic sound is the snort or snuff of a charging or defensive bison, which is loud and forceful. If you are viewing bison from a safe distance in a park or refuge, you are unlikely to hear them unless they are alarmed or breeding activity is occurring. The sounds complement the visual identification: a large, dark, humped animal that produces a deep, resonant vocalization is definitely a bison and not elk, deer, or cattle.

Newborn bison calves are reddish-brown or tan in color, a striking contrast to the dark adults, which makes them very easy to spot in spring when calves are born. Calves weigh 30 to 50 pounds at birth and grow rapidly, gaining up to 2 pounds per day on their mother's milk. By their first winter, calves have darkened considerably and weigh several hundred pounds, though they are still noticeably smaller and more slender than adult bison. By age two, young bison approach adult size and have developed the full dark coat and hump typical of the species. In North Dakota's refuges and parks, seeing a tan or reddish calf alongside a large dark adult is common in late spring and early summer. The stark color difference between newborn calves and adults is one of the most distinctive field markers of young bison and helps you identify family groups or cohorts moving together through grasslands.

North Dakota is home to several large animals, but bison are in a class by themselves in terms of sheer mass and presence. Elk are the second-largest grazing animal in North Dakota and reach 5 to 5.5 feet at the shoulder with bulls weighing up to 700 pounds, but they lack the bison's pronounced shoulder hump and are built more lightly and delicately. Deer, even large mule deer, are far smaller, typically 3.5 to 4 feet tall and rarely exceeding 250 pounds. Moose do not live in North Dakota and are found only in the far north. Bison are instantly recognizable by their bulk, hump, and broad head compared to any of these animals. At a wildlife viewing area in North Dakota, if you see an animal that could potentially weigh over 1,000 pounds and has a massive shoulder hump, it is a bison. The comparison is straightforward: bison are the largest, most heavily built grazing animal in the state, and no other resident mammal is close in mass or presence.

If you encounter a bison in North Dakota, whether in a refuge, park, or more open area, maintain a safe distance and never approach on foot. Bison can charge if they feel threatened, and their speed and power make them dangerous despite their seemingly placid appearance. Most North Dakota parks and refuges have marked viewing areas or designated trails; stay on these paths and use binoculars or a camera with a zoom lens to observe from a distance. During rut in mid-summer, bulls are particularly aggressive and territorial, so extra caution is warranted. If a bison shows signs of agitation, such as raising its tail, stamping its hooves, snorting, or lowering its head toward you, back away slowly and give it room. Photography and quiet observation from vehicles or designated platforms are safe ways to enjoy bison in North Dakota. Most park staff can advise on current bison locations, activity levels, and best viewing times, which change seasonally and by herd. For field trips to see bison in North Dakota, start with theparent trunk guidefor specific locations and seasons, or check state park websites for the latest information and access rules.