I live close to Green Mountain and am actually more afraid of rattlesnakes than any other type of wildlife in the area. Here is a list of wildlife that can present dangers to humans and/or pets known to frequent the west suburbs of Denver:
Coyotes, Foxes, Hawks, Mountain Lions, Rattlesnakes, Elk, Deer, and very rarely, Black Bear.
I’ve seen or been told about all of the above in my own neighborhood except black bear. But they have been spotted in close neighboring areas by people I know. I do live in an outlying area surrounded by a lot of open space so it stands to reason there is more wildlife in my area of “Denver.” I work in the city and rarely spot any dangerous wildlife in Denver proper, save the occasional coyote. Saw a den of them on a vacant lot in Cherry Creek North a few years ago. I wouldn’t be afraid of a coyote personally but they can present risks to pets and small children.
Many years ago our cat had a run-in with a hawk trying to render him as lunch. In another incident, a fox or coyote, we aren’t sure which, also tried to eat him. He successfully defended himself both times, not without injury and a visit to the vet, and he is much the wiser for it now.
My biggest concern for our son when he was little was our neighbor’s dog who was constantly getting loose. And venomous snakes that are seen every summer in our neck of the woods. Never seen one in my own yard, but my neighbors sure have.