ARS | Publication request: Impacts of feral horse use on rangelands and riparian areas

Submitted to: Society for Range Management Meeting Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: October 25, 2011
Publication Date: February 9, 2012
Citation: Davies, K.W., Boyd, C.S., Collins, G., Petersen, S. 2012. Impacts of feral horse use on rangelands and riparian areas[abstract]. 65th Annual Society for Range Management Meeting Proceedings. Paper No. 0008.

Technical Abstract: Feral (wild) horse impacts on rangelands and riparian areas are largely unknown. The impacts of feral horses are often indistinguishable from domestic livestock impacts because livestock grazing occurs across most horse herd management areas. However, the Sheldon National Wildlife Refuge has a large feral horse population and livestock grazing has been excluded since the early 1990’s, thus providing a situation where the impacts of horses can be evaluated. To determine the impacts of horses, we excluded horses from five riparian and rangeland plots starting in 2008. We compared the plots protected from horse use with adjacent plots where horse use was not restricted. Rangeland plant community change has been slow with horse exclusion with small increases in perennial herbaceous vegetation. However, sagebrush density has increased with protection from horses and may improve habitat for sagebrush associated wildlife species. Riparian areas have responded more to horse exclusion with bare ground decreasing by approximately 300%. Riparian plant community composition also appears to be changing with horse exclusion. Unmanaged use by feral horses is negatively impacting riparian areas and rangeland; however, the magnitude of impacts largely depends on level of use.