The lawsuit, filed by the Alliance for the Wild Rockies and Council on Fish & Wildlife, comes less than three weeks after the state of Montana also sued the park.

Photographer Drew Simms braved extreme winter conditions in Yellowstone National Park to document its wildlife enduring a freezing temperatures as low as -37°F (-38.3°C). Over a week-long expedition, ...

Pour one out for Speedy. The 24-year-old bison was a beloved member of the Yellowstone National Park ecosystem. Sadly, the animal passed away while in her enclosure at the Yellowstone Wildlife ...