Presented by Colorado Bird Atlas Partnership:

The Second Colorado Breeding Bird Atlas


Atlas History

The Second Colorado Breeding Bird Atlas (Atlas II), conducted from 2007 to 2012, marked a 20-year interval since the first Colorado Breeding Bird Atlas (Atlas I) effort (1987–1995). The results of Atlas I, published in 1998's Colorado Breeding Bird Atlas (H. E. Kingery, Ed.), provide a resource widely used by wildlife professionals, birders, and educators. Field work for both Atlases was completed primarily by volunteers, who collected data on the distribution, habitat use, and breeding phenology of Colorado’s avifauna. Atlas II compares the results of both Atlas efforts and presents valuable information on changes in species distribution over time. Atlas II also presents updated habitat use data and breeding phenology windows—important information for wildlife and natural resource professionals managing Colorado’s extensive public lands.


Breeding Bird Atlases contain important knowledge for the conservation of Colorado’s avifauna. They convey information on bird distribution; and, when repeated at regular intervals, they show how these factors changes over time. State, federal, tribal, and private landowners can use this information to set priorities for conservation activities and to monitor the effectiveness of current land management practices. The Second Colorado Breeding Bird Atlas had these objectives:

  • Document current distribution of breeding birds in Colorado
  • Assess changes in species distribution since the Atlas I
  • Confirm breeding activities for new Colorado species
  • Increase knowledge of species habitat use and breeding phenology
  • Identify important breeding areas for threatened, endangered, sensitive, or rare species