Calliope Hummingbird is not really a rare bird in Larimer County in the present century, but when the Sibley Guide was published it was considered a rare mid-summer southbound migrant in the western, mountainous region of the state of Colorado. Now, in 2012, it is an uncommon migrant throughout western Colorado and the front range of the Rockies, only becoming rare on the eastern plains.
The bird photographed in this gallery has been hanging out in a private garden in southeast Fort Collins, CO. I believe it is a juvenal male, because of the one red feather in the center of the throat.