Finding black-footed ferrets on the Fort Belknap Reservation with forward looking infrared cameras.
By Kristy Bly, WWF NGP Black-footed Ferret Restoration Manager
This work was possible due to a partnership between FLIR Systems (https://www.flir.com/), Fort Belknap Fish and Wildlife Department (https://ftbelknap.org/), Gantz-Mountain (http://testsite.gm-ias.com/mt-5-options/), SBB Research Group (https://www.sbbrg.org/), U.S. Fish and Wildlife Service (https://www.fws.gov/endangered/), and World Wildlife Fund (https://www.worldwildlife.org/places/northern-great-plains).
In this case study from WWF’s Northern Great Plains Program, Black-footed Ferret Restoration Manager Kristy Bly discusses how infrared FLIR cameras help teams detect and monitor the highly endangered black-footed ferrets living on the Fort Belknap Reservation plains in Montana. The ability to monitor ferret populations is crucial for the protection of this recently-reintroduced species, with fewer than 300 black-footed ferrets currently living in the wild.
Through population monitoring and disease control, WWF and their ferret recovery program partners hope to restore the population on the Northern Great Plains, with a goal of having 3,000 adult ferrets thriving in the wild.
n a remote part of north central Montana on the Fort Belknap Reservation exists a small but flourishing population of black-footed ferrets. Fort Belknap first reintroduced ferrets in 1997, becoming the 6th federally designated reintroduction site, and notably, the first reintroduction to occur on Tribal lands. Unfortunately, an epizootic outbreak of sylvatic plague, a non-native disease lethal to ferrets and their prairie dog prey, occurred in 1999 and decimated populations of both species.
Since then, however, prairie dog populations rebounded, and plague mitigation tools became available. In 2013, the Fort Belknap Fish and Wildlife Department (FWD) wanted to return ferrets to the Reservation once again and invited the World Wildlife Fund (WWF) and U.S. Fish and Wildlife Service (USFWS) to assist them. FWD and WWF conducted prairie dog surveys on the Reservation and the USFWS determined there was sufficient habitat and prey availability to warrant a ferret reintroduction.
Thus, 67 ferrets were reintroduced to the Reservation during 2013 – 2015; annual sylvatic plague mitigation occurring and technical and financial support from WWF and USFWS (and others), this population is thriving and producing kits. To keep ferrets thriving on the Reservation requires continued commitment by FWD and innovation.
The black-footed ferret is one of the most endangered mammals in North America; fewer than 300 individuals exist in the wild today. To effectively design conservation interventions—and reach the recovery goal of 3,000 adults in the wild—we need to estimate the size and health of existing wild populations. But detecting and observing these nocturnal, burrow-dwelling animals is a challenge.
The most effective monitoring tools to date are high-intensity spotlights mounted to truck windows or roofs, which we use to search for ferrets living in prairie dog colonies by looking for their tell-tale emerald green eyeshine. While effective, this technique relies heavily on field capacity and unobstructed views—and observers must move constantly to bring new areas into view. In addition, ferrets are likely scared away by the light and truck sounds, further inhibiting our ability to estimate population numbers.
To address this challenge WWF, USFWS, and FWD – in partnership with FLIR Systems and with funding from the SBB Research Group – tested various forward-looking infrared (FLIR) cameras to locate ferrets on the Fort Belknap Reservation during 2019-2020. FLIR cameras use a thermal system that senses infrared radiation (body heat) of an individual, an advantage over searching for ferret eyeshine.
Our goal was to determine how effectively four FLIR camera models (FC-608O, Vue Pro, Scout, and Tao 2) 1) located ferrets at night; 2) distinguished ferrets from other animals (e.g., rabbits or badgers); and 3) estimated the number of ferret kits in each litter. We also wanted to compare each FLIR camera’s detection ability with that of the spotlights. We used a pan-tilt, roof-mounted system that supported a FLIR camera connected to a monitor mounted in the cab.
We found that the Tao 2 with a 100 mm lens was the most useful of the four cameras. However, we encountered a discrepancy between the focus and clarity of the FLIR camera and the monitor-produced images. Images of ferrets on the monitor appear fuzzy; the only way we can correct the image is to move closer to the target.
We were also interested in the application of Artificial Intelligence to automatically detect ferrets and notify us to their locations. In 2020, WWF partnered with Gantz-Mountain to test their MT-5-R Long Range Intelligence Sensor Node system. The Gantz-Mountain MT-5-R boasts a BOSON 640 FLIR camera, artificial intelligence capabilities, an onboard radio, intelligent sensor nodes, and is capable of transmits clear images of the target to a monitor. We assessed the MT-5-R system by the same set of goals used to assess the first four FLIR models.
The system effectively identified and tracked ferret-sized animals from 500 meters away, often before they were visible in the spotlight. This automation made it easier for WWF and partners to locate ferrets living on the Reservation.
Measuring progress toward recovery of this rare species relies on estimates of their numbers in the wild. FLIR’s thermal imaging infrared cameras combined with Gantz-Mountain’s smart-edge surveillance systems are a promising black-footed ferret detection tool – one that WWF and partners will continue testing.
Thank you to WWF’s Northern Great Plains Program for sharing their work and images with WILDLABS, and to FLIR Systems, Fort Belknap Fish and Wildlife Department, Gantz-Mountain, SBB Research Group, and U.S. Fish and Wildlife Service for letting us feature this project.
Read more about WWF NGP’s work with ferrets and prairie dogs here.