Reintroducing the Dakota skipper

150 years ago, Minnesota had 18 million acres of prairie. Today less than one percent remains, with the rest developed or converted to agriculture. Prairies are among our state's most altered habitats and contain the most species of the greatest conservation need.

The Dakota skipper (Hesperia dacotae) is one of several butterflies that used to be common in Minnesota's prairies. It is a prairie obligate, and requires open prairie filled with mostly native plants. An obligate species is one that almost always exists in the same place, in the same environmental conditions - it requires a very specific habitat to survive.

In the early 2000s, for unknown reasons, almost all of Minnesota's Dakota skippers disappeared. The last Dakota skipper found at Glacial Lakes State Park was in 2005, and in 2014, the butterfly was listed as federally threatened under the Endangered Species Act.

Prairie habitat work at Glacial Lakes State Park

The park's lush tallgrass prairie is special because it has wet basins and dry hilltops that support a dynamic tapestry of plants and animals. Eighty percent of this prairie is designated as critical habitat under the Endangered Species Act.

The climate in this area has become warmer and wetter, which accelerates shrub and tree growth that threaten the prairie. Park staff use many tools to manage this threat: 

• Sumac and other brushy species are carefully treated with herbicide designed to kill the woody stems and cause little permanent damage to grasses and flowering plants.
• Large-scale mulching, mowing and tree thinning help reduce the woody cover and reclaim many acres of prairie savanna.
• Prescribed burns and grazing cattle help maintain the open landscape and encourage flowering plants to bloom, providing nectar for pollinators.

Reintroducing Dakota skippers in the park

In 2019, Minnesota State Parks and Trails partnered with the Minnesota Zoo and the U.S. Fish and Wildlife Service on a Dakota skipper conservation initiative, with the goal of re-establishing the lost self-sustaining wild population at Glacial Lakes State Park. 

Funded by Minnesota's taxpayers through the Environmental and Natural Resources Trust Fund and the Parks and Trails Legacy Fund, the project supports the Minnesota Zoo's Dakota skipper breeding and rearing program and helps fund critical habitat management in the park.

Before Dakota skippers could be returned to the park, woody stems were reduced in 200 acres of degraded prairie habitat and 50 acres of trees were thinned from savannas.

Dakota skippers favor narrow-leafed purple coneflower (Echinacea angustifolia). Males use hilltops during mating season to attract females, so the prairie hilltops were planted with coneflower seeds and plugs, as well as other prairie plants beneficial to the skippers. Park staff actively manipulate native flower and grass composition to benefit rare butterflies and other prairie pollinators. 

Sorting prairie seeds to plant.

Staff hold trays of prairie plugs, ready to plant.

July 2023: Cale Nordmeyer, Minnesota Zoo butterfly biologist, carefully reintroduces Dakota skippers to the prairie.