Office of External Affairs
Mountain-Prairie Region


U.S. Fish and Wildlife Service
Mountain-Prairie Region
134 Union Boulevard
Lakewood, Colorado 80228

Sept. 21, 2009


U.S. Fish and Wildlife Service and Colorado Department of Wildlife block clear eastern Colorado’s black-tailed prairie dog habitat 


Contacts: Susan Linner: 303.236.4774;

                Sandy Vana-Miller; 303.236.4748;


The U.S. Fish and Wildlife Service (Service), in coordination with the Colorado Department of Wildlife, has block-cleared all black-tailed prairie dog  habitat in eastern Colorado after determining that these areas no longer contain any wild free-ranging black-footed ferrets.


Block clearance means that activities within these areas that result in the removal of black-tailed prairie dogs (Cynomys ludovicianus) and/or their habitat will no longer be required to meet the Service’s survey guidelines for black-footed ferrets, or undergo consultation under the Endangered Species Act (ESA).  This clearance does not include white-tailed and Gunnison’s prairie dog habitats that may occur within the mapped block-cleared area.


“Based on the best science available we’ve concluded that the eastern half of Colorado is free from black-footed ferrets. As a result, we’ve block cleared the region for activities affecting black-tailed prairie dogs,” said Susan Linner, Field Supervisor of the Colorado Ecological Services Office. “This change in policy means less consultation requirements for landowners. However, this easing of policy only applies to black-tailed prairie dog habitat at this time.”


The black-footed ferret (Mustela nigripes) is a federally listed endangered species that depends upon prairie dogs as a source of food and uses their burrows for shelter.  Any actions that kill prairie dogs or reduce their habitat could prove detrimental to black-footed ferrets (ferrets) occupying the affected prairie dog towns.  However, some activities are also likely to be inconsequential to ferrets even if ferrets were to exist on a given prairie dog colony, while other actions such as prairie dog control could result in ESA violations. 


The Service will continue to collect data on black-tailed prairie dog populations, including information about planned control activities.


The mission of the U.S. Fish and Wildlife Service is working with others to conserve, protect and enhance fish, wildlife, plants and their habitats for the continuing benefit of the American people. We are both a leader and trusted partner in fish and wildlife conservation, known for our scientific excellence, stewardship of lands and natural resources, dedicated professionals and commitment to public service. For more information on our work and the people who make it happen, visit


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