Fort McCoy’s butterfly management program demonstrates how conservation, military readiness coexist

While Fort McCoy is widely recognized for preparing America’s military forces for missions around the world, another mission quietly unfolds each spring and summer across the installation’s oak barrens and prairies.

It is a mission focused on conserving some of Wisconsin’s rarest butterflies.

For decades, Fort McCoy’s Directorate of Public Works Natural Resources Branch (NRB) has managed thousands of acres of habitat that support rare and declining butterfly species. Through scientific research, habitat restoration, and partnerships with federal and state agencies, the installation has become one of the Army’s premier examples of balancing military readiness with environmental stewardship, said Endangered Species Biologist Jessup Weichelt.

At the center of that effort is the federally endangered Karner Blue Butterfly, one of North America’s most recognizable conservation success stories.

Protecting a national treasure

The Karner Blue Butterfly depends entirely on one native plant during its early life cycle — wild blue lupine. Without lupine, the butterfly cannot survive, Weichelt said.

Fortunately, Fort McCoy’s sandy soils, oak barrens, pine barrens, and native prairie habitats provide ideal conditions for both lupine and the butterfly. Today, the installation supports one of Wisconsin’s largest remaining Karner blue butterfly populations, making it one of the species' most important strongholds in the Midwest.

Natural resource specialists manage this habitat through prescribed burning, selective tree and brush removal, invasive species control, prairie restoration, and long-term monitoring, NRB officials said. These practices help maintain the open landscapes that both military training and native wildlife require.

More than one butterfly

Although the Karner Blue is the installation’s best-known conservation success, it is only one of several rare butterflies that benefit from Fort McCoy’s habitat management program, Weichelt said.

The installation also supports one of Wisconsin’s largest known populations of the Frosted Elfin, a state-threatened butterfly that also relies on wild blue lupine.

Fort McCoy is equally significant for the Regal Fritillary, a Wisconsin-endangered butterfly whose caterpillars depend on native violets, Weichelt said. Once considered uncommon on the installation, the species has become an important focus of conservation efforts through continued prairie management.

Perhaps most remarkable is the Ottoe Skipper, another Wisconsin-endangered butterfly. Fort McCoy is home to the only known remaining population of the species in Wisconsin, making the installation critical to its continued survival within the state.

Natural resource staff also monitor monarch butterflies, whose populations have declined across North America. Habitat improvements that include preserving milkweed and diverse native flowering plants benefit monarchs as well as dozens of other pollinator species.

Together, these conservation efforts demonstrate that habitat management designed for one species often supports many others.

Conservation through stewardship

Protecting butterflies requires more than simply preserving land, Weichelt said.

Fort McCoy biologists conduct annual surveys during butterfly flight periods, map host plants, restore native vegetation, and evaluate habitat conditions across the installation. They also coordinate closely with training planners to ensure military readiness and conservation objectives remain compatible.

The installation’s Integrated Natural Resources Management Plan guides these efforts while supporting Fort McCoy's primary mission as one of the nation's premier Total Force training centers.

The result is a landscape where military training and wildlife conservation have successfully coexisted for decades.

Butterfly Field Days build partnerships An important part of Fort McCoy’s butterfly conservation program is the annual Butterfly Field Day, which brings together natural resource professionals, researchers, conservation organizations, university representatives, and state and federal agency personnel.

Hosted by Fort McCoy's Natural Resources Branch, the field day provides participants with opportunities to visit butterfly habitat, observe conservation techniques firsthand, discuss current research, and exchange ideas on habitat management and species recovery.

Participants often visit restoration sites, prairie and oak barrens management areas, and locations where rare butterflies and their host plants are monitored throughout the growing season. The event also showcases how military installations can successfully manage sensitive natural resources while maintaining a demanding training mission, Weichelt said.

By sharing lessons learned and innovative management practices, Fort McCoy helps advance butterfly conservation efforts well beyond its installation boundaries.

A model for the future

As pollinator populations continue to face challenges across North America, Fort McCoy’s butterfly conservation program demonstrates that thoughtful land management can produce lasting benefits for both wildlife and people, Weichelt noted.

The same prescribed fires, prairie restoration projects, invasive species control efforts, and habitat improvements that sustain rare butterflies also enhance ecosystem health, improve biodiversity, and support resilient training lands for future generations of Soldiers.

Through science-based stewardship, strong partnerships, and a commitment to responsible land management, Fort McCoy continues to prove that protecting endangered species and maintaining military readiness are complementary missions.

Each year, as visitors gather for Butterfly Field Day and watch Karner Blue butterflies flutter across blooming patches of wild lupine, they witness more than a conservation success story. They see decades of collaboration, careful stewardship, and dedication that ensure Fort McCoy remains both a premier military training installation and one of Wisconsin’s most important refuges for some of its rarest butterflies.

Fort McCoy’s motto beginning in 2026 is “Training the Total Force and Shaping the Future since 1909.” The installation’s mission: “Fort McCoy strengthens Total Force Readiness by serving as a training center, Mobilization Force Generation Installation, and Strategic Support Area enabling warfighter lethality to deploy, fight, and win our nation’s wars.” And Fort McCoy’s vision is, “To be the premier training center supporting the most capable, combat-ready, and lethal armed forces.”

Located in the heart of the upper Midwest, Fort McCoy is the only U.S. Army installation in Wisconsin. The installation has provided support and facilities for the field and classroom training of more than 100,000 military personnel from all services nearly every year since 1984.

Learn more about Fort McCoy online athttps://home.army.mil/mccoy, on Facebook by searching “ftmccoy,” on Flickr at https://www.flickr.com/photos/fortmccoywi, and on X (formerly Twitter) by searching “usagmccoy.” Also try downloading the My Army Post app to your smartphone and set “Fort McCoy” or another installation as your preferred base.

Fort McCoy is also part of Army’s Installation Management Command where “We Are The Army’s Home.”