

A grizzly bear killed a man who was hiking with his wife in Yellowstone National Park's backcountry in Wyoming after the couple apparently surprised the female bear and her cubs on July 6, park officials said. It was the park's first fatal grizzly mauling since 1986, but the third in the Yellowstone region in just over a year. Design Pics/Newscom/File
More than 3,000 bison roam the grasslands of Yellowstone National Park in any given year. Bison are capable of speeds in excess of 30 mph. Each year, bison injure park visitors who approach too closely. Janie Osborne/AP/File
A bison calf stands in Yellowstone National Park in Wyoming. Ann Hermes/Staff/File
A wolf watches biologists in Yellowstone National Park after being captured and fitted with a radio collar. Before wolves were reintroduced in 1995, the last wolves in Yellowstone were killed in 1926. No humans have been killed by wolves since the reintroduction. Courtesy of US Fish and Wildlife Service/File
A bull elk bugles in Yellowstone National Park. Elk are extremely protective of their young, and have been known to attack people. Rolf Nussbaumer/DanitaDelimont.comNewscom/File
A black bear rubs itself against a tree near the Rainy Lake near Tower Fall in Yellowstone National Park. Black bears are omnivores and thrive in a variety of habitats. Smaller than grizzly bears, black bears are more numerous and therefore come into more conflict with humans. Jim Urquhart/Reuters/File
A mule deer buck is on high alert at Yellowstone National Park. Cindy Miller Hopkins/DanitaDelimont.com/Newscom/File
A coyote searches for food in Yellowstone National Park. Coyote attacks on people are extremely rare and usually are limited to small children. Ann Hermes/Staff/File
Bighorn sheep demonstrate their agility on a rock face in Yellowstone National Park. Lynn Seldon/DanitaDelimont.com/Newscom/File
A red fox pauses in the snow in Yellowstone National Park. Fox attacks on humans are not common. Charles Sleicher/DanitaDelimont.com/Newscom/File