Yellowstone is trending after a 57-year-old man was mauled to death by a grizzly bear in one of the park’s backcountry areas. The victim was hiking on the Wapiti Lake Trail with his wife, who was also rushed by the bear but survived. Yellowstone officials believe the mother grizzly attacked because she felt her cubs were being threatened. Park rangers are currently looking for the bear. But since she acted naturally, officials say she will not be killed. The trail near the attack has been closed, and warning signs have been posted. While it’s the park's first fatal bear attack since 1986, it's the third in the Yellowstone area in just over a year.