The recovery of three federally protected butterflies, poweshiek skipperling (US endangered), mitchells satyr (US endangered), and dakota skipper (US threatened), will hinge on protected habitats that…

The U.S. Fish and Wildlife Service awarded a $225,000 Project Grant under the Endangered Species Recovery Implementation program (CFDA 15.657) to the Minnesota Zoo. The grant funds a study to assess pesticide prevalence in habitats of three federally protected butterfly species - the Poweshiek skipperling, Mitchell's satyr, and Dakota skipper. The research aims to close knowledge gaps about pesticide exposure in currently occupied, extirpated, and potential reintroduction sites across the historic ranges of these endangered butterflies. This large-scale sampling effort across multiple U.S. states and southern Canada will inform recovery strategies, reintroduction programs, and habitat management decisions to support the conservation of these species. The project is a partnership between the Minnesota Zoo and Michigan Natural Features Inventory, and will be implemented from February 2024 through May 2027.

The recovery of three federally protected butterflies, poweshiek skipperling (US endangered), mitchells satyr (US endangered), and dakota skipper (US threatened), will hinge on protected habitats that provide necessary resources and limit stressors. Indeed, formal recovery plans for these three species identify the need for increases in the number of healthy and robust populations to achieve recovery criteria. Formal recovery plans define a healthy population as one that is demographically, genetically, and physically robust and occupies large areas of high-quality remnant prairie habitat (U.S. Fish and wildlife service 2021, 2022). To be robust, a population must be comprised of individuals with good body condition and with pesticide and pathogen loads that are below levels that could cause meaningful loss of reproductive capacity (U.S. Fish and wildlife service 2022). Thus, the risks associated with pesticide exposure must be one of the formal factors considered when assessing the health ofexisting populations as well as locations for potential reintroductions (e.g., delphey ET AL. 2017). Pesticides are one of the key hypothesized threats to these insects and the fragmented habitats upon which they depend. However, information gaps exist about the prevalence of pesticides within occupied sites, critical habitats, and particularly other potentially suitable areas for these endangered butterflies. The MN ZOO seeks to close these knowledge gaps by significantly expanding the geographic and seasonal scope of non-target pesticide occurrence sampling within key habitats of dozens of sites across the historic ranges of these butterflies. These sites will include currently occupied, extirpated sites, as well as candidate sites for potential future reintroductions or other forms of translocations. This project will provide an assessment at a scale that is necessary for better understanding the scope of a key hypothesized stressor across a large geographic range, and will inform recovery implementation strategies, reintroduction programs, and habitat management decisions. With sampling sites in multiple US states and in southern canada, the project crosses two FWS regions (3 and 6) and is international in proposal for recovery implementation fund opportunity f-FWS-ES-23-101: pesticide risk in potentially suitable habitats for endangered butterflies. The research is a partnership with the minnesota ZOO and michigan natural features inventory.