Response of nontarget species to underground strychnine baiting for pocket gopher in southwest Oregon

Pocket gophers (Thomomys spp.) impede reforestation efforts in the Pacific Northwest and strychnine baiting is used to reduce their populations. We conducted a capture and release program in southern Oregon to determine whether strychnine baiting negatively impacted nontarget small mammal species. Two nontarget species dominated the program: golden mantled ground squirrels (Spermophilus lateralis) and yellow pine chipmunks (Tamias amoenus). There was a short-term decline in ground squirrel populations after baiting, but yellow pine chipmunk populations were not adversely affected. We conclude that underground baiting with 0.5% strychnine treated grain is unlikely to cause long-term adverse effects on nontarget wildlife species in southwest Oregon.