Residents in parts of Boulder have reported seeing the animals during the day, and coyotes are blamed for killing several cats.
Tuesday was the first day of sales for late summer and fall tags for animals like elk and bear.
Scientists are using robots to study the Greater Sage-Grouse to better protect the bird, which is threatened in Colorado.
Eric Larsen just finished two months and 500 miles of skiing, snowshoeing and swimming to the North Pole. It's a trip he says could soon be impossible to complete.
David Sibley writes and illustrates some of the most famous bird guides in the world. He’s in the state to see the Gunnison Sage Grouse, the last North American bird on his life list.