Colorado has a number of birders who keep various life and annual lists. This becomes a friendly competition which measures skill and effort. Birders enter their totals by county each year. The various reports then summarize those geographically.
One special list, unique to Colorado, is the Fourteeners/400 club. This list recognizes people who have summited all of Colorado's 14,000 foot peaks and have seen at least 400 species of birds in the state.