Resurrection and resilience of the rarest butterflies

For as long as I can remember, I have been attracted to things that are rare. As a child, these things included coins, stamps, and football cards. When I was invited as a young professor to lead efforts in science and conservation of one of the world’s rarest butterflies, I accepted enthusiastically. Beginning in 2002, I focused my efforts on conservation and recovery of St. Francis’ Satyr (Neonympha mitchellii francisci) and its small remaining populations. I am by nature an over-optimist, and I knew (or hoped anyway) I could succeed and conserve the butterfly quickly. The only place in the world that St. Francis’ Satyr can be found is in southern North Carolina. It has required active conservation since the subspecies’ discovery in 1983 at the Fort Bragg Army Installation. At that time, its total worldwide population was thought to number 100 butterflies in one population that occupied 1 ha in area [1]. By 1990, the population had declined to zero, and the subspecies was declared extinct (left half of Fig 1A) [2]. St. Francis’ Satyr’s resurrection was nearly as surprising as its original discovery. In 1993, Fort Bragg biologist Erich Hoffmann discovered a population in the most inaccessible place, the range where the army fires guns, flares, and heavy artillery. With this new knowledge and with a wider search of the installation, Hoffmann found St. Francis’ Satyr to occupy 10 ha of wetlands. Although a tiny area, it provided an apparently stable starting point from which my lab could work to expand and grow populations. St. Francis Satyr’s physical features are unremarkable. It is small and brown. Most frequently, I see individuals sitting low on blades of grass. The butterfly lives along streams in open, grassy wetlands. A common assumption in conservation is that if we can exclude people from wild places, those landscapes—and the populations they support—will recover. So I set out to keep people, including scientists and soldiers, out of the way. I set up initial hands-off prescriptions, sat back. . .and watched the populations slide toward extinction. I am at the same time bemused and appalled as I look back on my initial self-assuredness. Of seven populations that my group monitored outside artillery ranges, I watched as one was extirpated in 2003, the next in 2005, and the next three in 2008, 2009, and 2010 [3]. When I began my efforts in 2002, the population size of St. Francis’ Satyr reached 1,500. By 2011, it had descended to 100 [4]. Despite my effort and oversight, extinction appeared inevitable. As I watched populations collapse, there was one thing that nagged at me. St. Francis’ Satyr’s saving grace is that most of its total range is confined within areas that at first seem hostile: artillery ranges. Because these areas are nearly completely closed to access, the reasons