Detection of the endangered black-footed ferret Mustela nigripes using thermal-infrared cameras.

Evaluating how emergent technologies can complement traditional methods for detecting wildlife is particularly valuable when population management is based on detection-based metrics for rare or cryptic species of conservation need. The black-footed ferret (ferret; Mustela nigripes) is an Endangered species whose rarity and behavior (e.g. semi-fossorial and nocturnal) challenge our ability to monitor individuals and assess the status of populations. Here, we evaluated how applying the emergent technologies associated with thermal-infrared cameras can be used to detect ferrets in a reintroduced population on the Fort Belknap Indian Reservation, Blaine County, Montana, USA. We conducted nighttime surveys for ferrets using thermal-infrared cameras mounted to a tower and unmanned aerial vehicles (UAVs). We recorded 7 ferret observations using a stationary tower at a rate of 0.43 observations per survey hour. At least 5 individual ferrets were observed using this method for a rate of 0.31 individuals observed per survey hour. Similarly, we recorded 8 ferret observations using UAVs for an observation rate of 0.41 observations per survey hour. At least 6 individual ferrets were observed using this method for a rate of 0.31 individuals observed per survey hour. Our findings suggest that the use of thermal-infrared cameras could benefit conservation and management efforts for the ferret or other similar species, providing a tool for detecting these elusive species that creates less disturbance to the landscape and alleviates potential navigation challenges associated with ground-based survey methods. The use of thermal-infrared cameras deployed as described here could therefore serve to complement traditional survey techniques for this Endangered species.