An American bison attacked a man in Wyoming's Yellowstone National Park on Tuesday, the second such incident in a month and a reminder that the large, territorial animals are unpredictable, experts say.
The 62-year-old Australian man was taking pictures when he came within a few feet of the bison, which was lying on the grass near Old Faithful Lodge.
The animal got up and charged, tossing him in the air several times and causing serious but not non-life threatening injuries, according to a Yellowstone National Park press release.
In May, a 16-year-old Taiwanese girl was gored—and survived—while posing for a picture with a bison near Yellowstone's Old Faithful geyser.
"Bison are unpredictable, wild animals that do not like their space encroached," Traci Weaver, a public affairs officer for the park, says by email.
A male bison weighs about 2,000 pounds (900 kilograms), and females weigh about 1,100 (500 kilograms). The agile, aggressive creatures can run up to 30 miles (48 kilometers) an hour, she adds.
That can make for a dangerous situation when the annual hordes of summer tourists descend on national parks such as Yellowstone and get pushy in their quest for the perfect photo-op. (See National Geographic's tips for photographing wildlife.)
"Eyewitnesses reported that several people were harassing this bison, trying to get pictures with it," says Weaver.
"Bison are wild animals, and they do not like being crowded or harassed. They will do what they can to protect their space, or protect their young."
Respect Bison Boundaries
Despite the nearly 5,000 bison that call the park home, such incidents aren't common at Yellowstone—usually one or two a year, said Weaver.
Weaver says people should steer clear from bison when visiting the park, maintaining a distance of at least 75 feet (22 meters) from the animals and avoiding them on trails or boardwalks entirely. (Also see "How to Put a Camera on a 1,000-Pound Bison.")
It's basically straightforward: Be smart and respect the animals' limits.
"People need to understand that while bison may appear tame and docile, they are truly wild animals. While they may seem uninterested in people, they all have a tolerance limit."
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