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, ...

But Paunovich soon realized it was Canis lupus: the gray wolf. The last wolves seen in Yellowstone — two pups — were killed ...

This grassland valley north of Yellowstone Lake is a highly visited gathering place for bison, elk, coyotes and grizzly bears. In fact, Hayden Valley is home to the largest rut of free roaming ...