Visiting birders to Colorado tend to fall into two main categories:
Many come in April for a Colorado “Chicken Tour” to enjoy the grouse, prairie-chickens, and ptarmigan. Another major wave of birders visit in the breeding season (May-July) for the great variety of Colorado specialities. But the fall season also offers tremendous birding opportunities.
Rocky Mountain National Park by Andrew E. Russell via Flickr
Pawnee Buttes Storm Clouds by Michael Kirsh via Flickr
If you are interested in seeing which birds can be found in either Rocky Mountain National Park or the Pawnee National Grasslands, the links below will show you the species that are reported to eBird from these two globally Important Bird Areas during September through November: