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Minnesota is home to diverse prairie butterfly fauna, but several species have recently undergone drastic population declines. For example, 10 of the 15 butterfly species classified as Endangered, Threatened, and of Special Concern by the State of Minnesota depend exclusively on native prairies. The declines of two of these, the Dakota Skipper and the Poweshiek Skipperling, have been so precipitous that they are now exceedingly rare despite having been predictably common previously. Poweshiek Skipperling is now on the verge of global extinction. Multiple regional and local factors may have contributed to these declines, and those factors are expected to have interacted in various ways. However, a working hypothesis is that these butterfly declines are at least in part the result of insecticide drift related to management of the soybean aphid, which invaded Minnesota in 2000 and led to substantial increases in insecticide applications to soybeans. On November 15, 2016, the Minnesota Invasive Terrestrial Plants and Pests Center (MITPPC) in collaboration with the University of Minnesota Institute on the Environment held a workshop to assess hypotheses that could explain the butterfly declines. The workshop featured seven speakers from the US Fish and Wildlife Service, Minnesota Department of Natural Resources, Minnesota Zoo, University of Minnesota, and Environmental Protection Agency. The presentations, which MITPPC has posted online (http://z.umn.edu/mitppcbutterfly), focused on three themes: (i) biology and conservation status of the endangered butterflies, (ii) the possible role of soybean aphid management in affecting butterfly populations, and (iii) risk assessment and potential solutions via conservation measures. The workshop fostered collaboration between experts in prairie conservation and agricultural pest management and featured extensive discussion between participants following the presentations. Members of the conservation and agricultural communities are typically not afforded the chance to engage ... |