Extirpation, colonization, and habitat dynamics of a keystone species along an urban gradient.

Extirpation, colonization, and habitat dynamics of a keystone species along an urban gradient.

Magle, S., Reyes, P. E., Zhu, J. and Crooks, K.

Biological Conservation 2010, 143, 2146–2155. DOI:10.1016/j.biocon.2010.05.027

ABSTRACT

Using 5 years of patch occupancy data for 384 habitat fragments, we evaluated population and habitat dynamics of the black-tailed prairie dog in urban habitat remnants in the rapidly developing landscape of Denver, CO, USA. Specifically, we evaluated the landscape factors, including fragment area, age, and connectivity, that characterize the habitat fragments most likely to be colonized by prairie dogs, as well as those experiencing local extinctions. In addition, we determined which patch types were most often removed by land development. Sites in proximity to colonies were more likely to be colonized by prairie dogs. Local extinctions were most common on isolated colonies, and older and more isolated colonies were more likely to be extirpated by human activity. In general, smaller and older habitat patches were at the highest risk of being lost to land development. Our results provide observations of dynamic changes to the distribution of a potential keystone species in an urban area, which can be used to inform island biogeographic and metapopulation models for wildlife persistence in developing landscapes. Although populations are currently in decline, most local extinctions are the direct result of human activity, and we suggest that prairie dogs in this area can persist with appropriate management.

KEYWORDS

Colonization, Connectivity, Extinction, Keystone, Prairie dog, Urban habitat