Proceedings of the Vertebrate Pest Conference

Baker Performance Chemical Incorporated entered into a cooperative agreement with the National Wildlife Research Center to evaluate acrolein as a fumigant for controlling northern pocket gophers (Thomomys talpoides). In October 1996, a 44.5 ha (110 acre) irrigated alfalfa hay field was selected as the study site in Franklin County, Washington. Eight treatment units (TUs), six fumigated, and two control, were established on the study site. On the six fumigated TUs, 58.9% of the sample plots were inactive, whereas, all sample plots (100%) on the two control TUs were active. The 58.9% mean reduction in pocket gopher activity on the six fumigated TUs was below the minimum efficacy standard of 70% established by the Environmental Protection Agency (EPA 1982). Possible reasons for the pocket gophers surviving the acrolein treatment are discussed.