FWS Protects Two Prairie Butterfly Species

By Mark Hofberg

A Poweshiek skipperling (Oarisma poweshiek) rests on a grassland flower. In an effort to protect declining butterfly habitat, the U.S. Fish and Wildlife Service recently listed the skipperling as endangered and the Dakota skipper as threatened under the Endangered Species Act. (Source: Mike Reese/wisconsinbutterflies.org).

The U.S. Fish and Wildlife Service (FWS) recently announced a decision to list two butterfly species for federal protection under the Endangered Species Act. The Dakota skipper (Hesperia dacotae), found in North Dakota, South Dakota, Minnesota, Manitoba, and Saskatchewan, has been listed as threatened while the Poweshiek skipperling (Oarisma poweshiek), found in Michigan, Wisconsin, and Manitoba, is now listed as endangered.

Both butterfly species have sustained large reductions in both range and population due to extensive losses of their grassland habitat from agricultural conversion. The Dakota skipperling can be found on only 25 percent of the sites it historically occupied while the Poweshiek skipperling can be found on only four percent of previously occupied sites. Scientists believe that the Poweshiek species has been totally extirpated from Minnesota, Iowa, South Dakota, and North Dakota.

FWS provided some regulatory exemptions for ranchers that use certain practices that help restore and maintain habitat for the butterflies. For example, some ranchers are enrolled in FWS and Natural Resource Conservation Service (NRCS) grassland and prairie easement programs that prevent cropland conversion. The Service referred to these voluntary conservation practices as the primary reason why the butterflies are still present on the landscape and noted that it hopes to continue working with landowners in future conservation efforts.

Sources: U.S. Fish and Wildlife Service (October 23, 2014), Federal Register (October 23, 2014)