A Comparison of Two Methods to Monitor Translocated Prairie Dogs

The effects of sylvatic plague and habitat fragmentation present species conservation challenges for prairie dogs (Cynomys spp.) and other wildlife species they support. Active reestablishment of extirpated prairie dog colonies may become increasingly necessary to achieve some conservation goals. We compared a passive-integrated-transponder (PIT) tag monitoring system and trail camera photographs to monitor short-term survival of captive dye-marked black-tailed prairie dogs (Cynomys ludovicianus) translocated into artificial burrows. We deployed cameras and a PIT-tag monitoring system in 2016 and 2017 (Nov-Sep) and collected 1.2 million PIT-tag scans and >255,000 photographs at a Colorado Parks and Wildlife facility near Fort Collins, Colorado, USA. There was no difference in the daily mean number of prairie dogs detected between the 2 monitoring methods (photographs x over bar = 3.40, PIT tags x over bar = 4.06). However, PIT-tag scans achieved a population census in 10 days (100% detected, 95% CI = 89-100%); whereas, photographs were able to detect only 67% of the prairie dogs during this same time (95% CI = 50-80%). Trail camera photographs of uniquely dye-marked individuals may be ideal for short-term monitoring (<= 6 months), while PIT tags are likely to outperform cameras in studies requiring efficient longer term monitoring of permanently marked prairie dogs. Although both monitoring techniques performed well in a semicaptive setting, how these techniques would perform when scaled to larger or more complex settings requires further research. (c) 2020 The Authors. Wildlife Society Bulletin published by Wiley Periodicals LLC on behalf of The Wildlife Society.