Summary

Description

Located approximately ten miles from downtown Denver, the Rocky Mountain Arsenal National Wildlife Refuge RMANWR encompasses 15,998 contiguous acres. Due to contamination from the production of chemical munitions and pesticides, significant portions of this site underwent environmental cleanup as stipulated in the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 CERCLA administered by the Environmental Protection Agency EPA. With the exception of about 1,084 acres that will be retained by the U.S. Army, the balance of land within the boundary was transferred to U.S. Fish and Wildlife Service jurisdiction following completion of remediation activities. Although most environmental cleanup was completed by the fall of 2011, native plant restoration activities continue on most lands.Restoration of short and mixedgrass prairie are considered to be of primary importance in achieving the purposes of RMANWR because these habitats provide the life requisites of numerous migratory bird species, many of which are considered to be species of conservation concern due to population declines. The large disturbance that occurred on this site has created conditions leading to high prairie dog populations, which is in conflict with larger goals for grassland restoration. Given that nonlethal methods have not been effective in controlling prairie dogs to the extent necessary to restore grasslands critical to achieving the purposes of RMANWR, alternative means of prairie dog control must be considered. Therefore, the goal of this adaptive management strategy is to develop a method, or combination of methods, that 1 increase the probability of restoration success and 2 sustain viable prairie dog populations that provide functions necessary to perpetuate native grasslands and associated migratory birds. The method selected to achieve the balance of active restoration within a landscape that includes prairie dogs in the RMANWR habitat management plan 2013 is to establish and maintain permanently designated prairie dog zones of 2,585 acres. The 2,585 acres represents approximately 16 of the total refuge, which is consistent with the historical accounts. These zones overlap much of the historical locations of prairie dog colonies on the RMANWR, and would be protected from sylvatic plague by application of appropriate insecticides to kill fleas, the intermediate host for the plague bacterium Yersinia pestis.