Two sharply declining populations of butterflies native to much of western Minnesota and elsewhere in the Midwest have been proposed for protection under the Endangered Species Act, federal officials said Wednesday, citing as the primary reason the loss of their natural prairie home.

The Dakota skipper is being proposed by the U.S. Fish and Wildlife Service (USFWS) as a "threatened" species. Found in Minnesota, the Dakotas and Canada, the Dakota skipper "has experienced a dramatic decline in numbers and no longer occurs on half the sites where [it was] previously found," the USFWS said in a statement.

The USFWS is proposing the Poweshiek skipperling for the more critical "endangered" status. Once found in Minnesota, seven other states and Canada, it now occurs only in a few native prairie remnants in Wisconsin and Michigan, and in Manitoba. Surveys indicate that Poweshiek skipperlings are gone from nearly 90 percent of the sites where they were previously found, the agency said.

The agency is attributing the species' declines to "degradation or changes" to their prairie habitat.

These species of butterflies are "representative of this dwindling piece of the prairie landscape that is declining," said USFWS spokeswoman Gerogia Parham. "They are little pieces in a big puzzle."

Tierra Curry, a conservation biologist at the nonprofit Center for Biological Diversity, based in Arizona, said, "These remarkable little butterflies have a long flight to recovery, but Endangered Species Act protection will help save them and their beautiful prairie homes."

Provided by the U.S. Fish and Wildlife Service, Star Tribune
Dakota skipper

Endangered species are plants and animals that are in danger of becoming extinct. Threatened species are those that may someday become endangered. The Endangered Species Act protects those listed from harm and conserves habitat designated as critical for the species' survival and recovery.

The USFWS is proposing to designate 54 tracts, ranging from 31 to 2,887 acres each, in Minnesota and the Dakotas as critical habitat for the Dakota skipper, an orange and brown species that is smaller but faster than most butterflies. This species is already on Minnesota's list of endangered butterflies.

For the light brown and orange Poweshiek skipperling, the agency is proposing to designate 63 tracts, ranging from 23 to 2,887 acres each as critical habitat in Minnesota, Iowa, Michigan, the Dakotas and Wisconsin as critical habitat.

The tracts in Minnesota run along the western edge of the state, top to bottom, in these counties for the Dakota skipper: Pope, Murray, Clay, Norman, Lincoln, Pipestone, Swift, Chippewa, Kittson and Polk. The designated tracts for the Poweshiek skipperling are in these western Minnesota counties: Pope, Murray, Clay, Norman, Lincoln, Pipestone, Swift, Chippewa, Wilkin, Lyon, Lac Qui Parle, Douglas, Mahnomen, Cottonwood.

"Over the next year, we will evaluate whether any of these tracts may be excluded from the final critical habitat designation, in cases where the benefits of excluding them outweigh the benefits of including them," the USFWS statement continued.

The service is also proposing a protection exemption for the Dakota skipper that would provide flexibility for landowners and land managers who have the species on their property. For example, the rule would allow incidental take of Dakota skippers as the result of routine ranching activities such as construction of fences, corrals and watering facilities; haying and mowing; and in some areas, grazing.

For more information on the agency's proposal, visit www.fws.gov/midwest/endangered.

Paul Walsh • 612-673-4482