Fort McCoy mitigation work helps create new habitat for Karner blue butterflies

By Rob Schuette, Fort McCoy Public AffairsNovember 26, 2012

Fort McCoy mitigation work helps create new habitat for Karner blue butterflies
Tim Wilder, Fort McCoy Endangered Species biologist, uses a Bobcat to create a Karner blue butterfly plant habitat section as part a mitigation project in the far northeast corner of Fort McCoy. Volunteer John Polk prepares to assist the seeding by r... (Photo Credit: U.S. Army) VIEW ORIGINAL

FORT McCOY, Wis. -- A range mitigation project at Fort McCoy means Soldiers can train on a new, upgraded range, while an endangered species of butterfly still has sufficient habitat.

Tim Wilder, installation Endangered Species biologist, said the mitigation project to create an alternate habitat for the Karner blue butterfly became necessary with the building of a 1,000 meter known-distance firing range. Karner blue butterflies, which are about the size of a quarter, are a federally endangered species found at Fort McCoy.

"When we sat down to see where to locate the new known-distance range, there were only so many places it could be located (due to land-use and environmental considerations)," Wilder said. "The best place was adjacent to Range 18, where a known Karner blue butterfly population occurred."

Initially, 14 acres would have been affected, Wilder said. After some reworking of the proposal, the affected habitat was reduced to four acres.

The Fort McCoy Natural Resources Branch (NRB) program, in cooperation with the Directorate of Plans, Training, Mobilization and Security (DPTMS), found another location in the far northeast corner of the post to create habitat being lost due to the new range project, he said.

DPTMS training officials agreed the proposed location for the new Karner blue butterfly habitat would not affect training opportunities. Wilder said some Karner blue butterflies already were in the area, so it was a matter of expanding the existing habitat.

Karner blue butterflies need wild lupine plants to support the larvae stage of the life cycle, he said. NRB personnel tilled the land and are planting wild lupine seeds. McCoy harvests its own wild lupine seeds, which can cost several hundred dollars per pound if purchased commercially.

The seeding is done on a ratio of about two pounds of wild lupine seed per acre.

"This is a good time of year to plant the seeds because they can take advantage of the freeze/thaw cycle this coming winter and spring and then germinate in April 2013," Wilder said.

The desired result is the plants would fully bloom in two years and be supporting the Karner blue butterfly population, Wilder said.

The seeding is done in narrow sections about 20-by-3 meters each. When the wild lupine takes hold, it is hoped the habitat area will further expand itself without any additional manmade assistance, he added.

Plants providing nectar for the adult Karner blue butterflies also are being added to the mitigation area to support the population. Wilder said adult Karner blue butterflies live for only about five to seven days. Although these butterflies live only a short time, the adults need flowering plants, such as butterfly weed and lead plant, to nectar on.

Fort McCoy has one of the largest Karner blue butterfly populations in the state and country, and management practices used by the installation help the butterfly prosper, Wilder said. The installation documented the first Karner blue butterfly in 1990 and has been actively managing the species for more than 15 years.

The installation also has several other thriving animal/mammal species on state or federal concern, endangered or threatened lists, including gray wolves and bald eagles, and several insects including other butterflies, he said.

Mark McCarty, chief of the NRB, said the mitigation project demonstrates that environmental stewardship can coexist with and support the installation's training needs.

Sound environmental practices and proactive natural resource management also help ensure Fort McCoy's land will be able to support Army training needs for future generations, he said.