The U.S. Department of Defense (DOD) manages over 10.1 million hectares of land, much of which is used for training military personnel. At Fort McCoy, Wisconsin, USA, populations of the endangered Karner blue butterfly ( Lycaeides melissa samuelis ) are found in oak and pine barren communities where wild lupine ( Lupinus perennis ), a perennial forb required by Karner blue butterfly larvae, still occurs. I conducted field studies during the spring and summer of 1996 and 1997 at Fort McCoy, WI to determine whether Karner blue butterfly distribution was related to within-patch, patch, or landscape characteristics, and the effects of military training on the density of lupine and Karner blue butterfly. In addition I developed a computer model (TRAINSIM) to determine which military training strategies and fire prescriptions were more capable of sustaining Karner blue butterflies and lupine; and developed an optimization model (OPTSIM) and scheduling model (SCHEDULER) to identify the parcel of land that can support military training, the length of time the land should be rested before training can re-occur, and how military training and Karner blue butterfly can be managed in the future.
At the within-patch scale, lupine stem density explained more variation in our index of abundance of Karner blue butterfly than any other measured factor. The abundance of lupine and nectar-producing plants was greater in the median strip between vehicle ruts than in vehicle ruts or 5 m outside the vehicle ruts. Within TRAINSIM, the military training strategy that excluded training from lupine five years and younger performed the best. Furthermore, OPTSIM determined that numbers of Karner blue butterfly were most abundant when military training was restricted for 1 or 2 years. SCHEDULER provided an easy-to-understand display that can potentially be used to schedule training. Military training was required to achieve Karner blue abundances significantly higher than when fire was the only disturbance, or training was excluded. However, Karner blue butterflies and lupine habitats could be reduced when military training was applied at incorrect locations and at inopportune times.