Yellowstone’s most injured visitors often got within 25 yards of a bison

Bison often appear calm while grazing beside Yellowstone roads and boardwalks, but that stillness does not make them safe at portrait distance. A review of injury records found that most injured people in the studied cases had approached the animals. The park’s 25-yard rule is therefore a behavioral boundary built from recurring close-contact failures.

Bison injure more Yellowstone visitors than any other animal

The comparison is easy to underestimate because predators appear more threatening. Bison are encountered frequently in developed areas, and their size can look slow through a phone screen. They can accelerate rapidly, pivot and use the head and horns against a person who has entered their defensive space.

Yellowstone’s current safety press kit says bison have injured more people in the park than any other animal and requires visitors to remain at least 25 yards away. If an animal moves closer, the visitor must back away to restore the distance rather than treating the approach as consent.

The injury study found approach behavior in 80% of cases

Researchers reviewed 25 bison-related injuries in Yellowstone from 2000 through 2015, involving 21 visitors and four employees. Twenty injured people had actively approached a bison; the other five did not retreat when one approached. The average visitor distance before injury was only 3.4 meters, far inside the park rule.

The published CDC and National Park Service case review identifies photography as the most common activity associated with approaching. The small historical sample does not predict every modern encounter, but it directly demonstrates a repeatable behavior preceding serious injuries.

Twenty-five yards is a minimum, not a viewing target

The rule translates to roughly the length of two full-size buses. That distance can disappear quickly if the animal begins walking toward a group. A telephoto lens or binoculars creates a close view without requiring a close body, and a vehicle often provides the safest viewing position where stopping is permitted.

People should not form a semicircle that blocks a bison’s movement. Even when every individual believes the animal has space, the combined crowd can remove its escape route. Backing away early avoids the sudden scramble that begins after head bobbing, pawing, bellowing or a raised tail appears.

A charge calls for movement and solid cover

Unlike common advice for some bear encounters, Yellowstone tells visitors not to stand their ground against a charging bison. The response is to move away and seek cover behind a vehicle, tree or other substantial barrier. Bear spray may be used while retreating if the animal continues following.

Speed and terrain matter. Looking through a camera narrows awareness, while turning a back for a selfie removes visual information about warning behavior. The safest photograph is framed after the distance has been established, not while stepping closer to improve the image.

Recent incidents repeat the same proximity problem

The National Park Service wildlife-health summary states that the majority of people hurt in the Yellowstone review approached bison despite the 25-yard regulation. The finding focuses prevention on a controllable choice: ending the approach before the animal has to react.

An animal can also enter the required distance on its own. Visitors remain responsible for moving away, even if that means abandoning a photograph, changing a trail plan or waiting inside a vehicle. The regulation protects the bison as well as the person because conflicts can lead to harassment, injury and management action.

Distance is easier to keep than to recover

Parking areas and thermal walkways can channel people toward wildlife, so extra time should be built into travel. A bison jam is not permission to leave a vehicle and walk through the herd. Patience allows the animals to move without creating a new cluster of people around them.

The documented pattern does not show that every injured visitor crossed exactly the same line. It shows that bison lead Yellowstone’s wildlife injuries, that most cases in a published series involved active approach and that injured visitors were usually far inside 25 yards. The park’s minimum distance turns those findings into a simple preventive rule: the close photograph is never worth entering the animal’s defensive space.

Group discipline helps enforce the rule when excitement rises. One person can watch the animal while another checks the route back, and adults can keep children from running toward an open view. If the bison changes direction, the entire group moves together. That planning prevents a crowd from discovering too late that parked cars, railings or other visitors have blocked the only safe retreat.

Season also changes behavior. During the summer rut, bulls may be more focused on other bison and less tolerant of interruption. Calves can make adults defensive at other times. The fixed distance rule avoids requiring visitors to diagnose that changing motivation at close range.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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