Swift fox re-introduction at Bad River Ranches, South Dakota, USA

Summary

The swift fox (Vulpes velox), listed as threatened in South Dakota and lost from 60-90% of its historical Great Plains range, was the target of a 2002-2008 restoration led by the Turner Endangered Species Fund at the privately owned Bad River Ranches, after an initial permit denial and a year-long public relations campaign won over skeptical agricultural groups and state regulators. Wild foxes captured in Wyoming and Colorado were ear-tagged, microchipped and radio-collared, then released using four methods: direct hard-release, short soft-release from pens, extended soft-release held through winter, and captive-born pups from long-soft-release pairs; 179 translocated foxes and 43 captive-born pups were released in total, alongside a coyote-control program since coyote predation limits fox population growth. Short-duration soft-releases produced the highest 60-day survival (0.757) compared to long-soft-release (0.659), hard-release (0.609) and captive-born releases (0.484); from 2003 to 2007 the population grew each year, with growth rates as high as λ=2.05 in 2007, tracking loosely with periods of lower coyote abundance. However, the release area proved only marginally suitable habitat, driving long-distance dispersal that removed animals from the breeding population, and the effort ended in 2008 after the tragic death of the project leader, with little evidence of swift foxes remaining by 2010. The project's own account credits strong grassroots landowner support, with nearly 100 neighboring landowners endorsing the effort, as proof of the species' value as a prairie conservation flagship, even though the population itself did not persist once management ceased.