Poweshiek Skipperling
Oarisma poweshiek (Parker)

Status: State Endangered (August 1, 1989).

Occurence: Occurs in Green Lake and Waukesha counties of Wisconsin.

Aid to ID: Wings are triangular and sharply pointed at the tips. Upper sides of the wings are dark grayish-brown with a somewhat lavender cast. The leading edges of forewings, and occasionally the base of the hindwings and veins have distinctive orange lines. The lower surface of the hindwing is pale brown with black on the inner margin. Underwing veins are lined silvery white. The wingspan is 0.9 -1.25 inches (27-31 mm).

Habitat: Poweshieks require wet mesic prairie habitat with native grasses, sedges, and a significant component of plants in the sunflower family. These wet communities often support JoePyeweed (Eupatorium maculatum), marsh milkweed (Asclepias incarnata), gayfeather (Liatris pychnostachya), big bluestem (Andropogon gerardii), and possibly cordgrass (Spartina pectinata). Favorite nectar sources are pale purple coneflower (Echinacea pallida), black-eyed susan (Rudbeckia sp.).and coneflower (Ratibida sp.). Larvae are reported to feed primarily on prairie dropseed (Sporobolis heterolepis) and little bluestem (Schizachyrium scoparium). When these plants are present in drier areas adjacent to the wetland, poweshieks can be found there as well.

Management Considerations: Each of the few sites in the state must be managed as the only remaining habitat for the species. Populations appear to exhibit fluctuations in size and small populations any given year combined with extremes of weather, management, or unforeseen events could cause local extirpations. Therefore efforts to expand habitat, create corridors between existing populations, and bolster population sizes are important for the long term survival of the species in Wisconsin. The poweshiek skipperling is fire-sensitive and burn management used to discourage woody plants and cool-season grasses in the open wet prairie community is best conducted with controlled infrequent burns affecting only a portion of the available habitat. Selective cutting and mowing may be better management tools for inhabited patches.

The content for this page was originally presented in the Endangered and Threatened Invertebrates of Wisconsin, a free publication available by contacting the Endangered Resources Program.