Cooperative Fish and Wildlife Research Units Program: all
Education, Research and Technical Assistance for Managing Our Natural Resources

Reliable prairie dog (Cynomys spp.) monitoring programs are important for assessing the status of prairie dog populations and selecting sites to reintroduce black-footed ferrets (Mustela nigripes). Estimating the density of active prairie dog burrows has been used as an index of prairie dog abundance. Indices derived from active burrow counts were developed for black-tailed (C. ludovicianus) and white-tailed (C. leucurus) prairie dogs, but their efficacy has not been evaluated for all prairie dog species and studies affirming their validity with more robust abundance estimators are few. We estimated the abundance of Gunnison’s prairie dogs (C. gunnisoni) in the Aubrey Valley, Arizona in 2006 at 2 different time periods using 4 different methods: maximum above ground counts (MAGC), minimum number known alive (MNKA), capture-mark-recapture (CMR), and mark-resight and compared these estimates to active burrow counts. We found no positive relationship between active burrow density and any metric of abundance. Mark-resight consistently produced estimates of abundance that were greater than the MNKA and were positively correlated with both the MNKA (r² = 0.30) and CMR estimates (r² = 0.49); other estimators were often biased low. Our results indicate that applying rigorous estimation methods may be necessary to accurately estimate prairie dog abundance and assess habitat quality for ferret management including reintroduction.