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Maintaining fire-dependent habitat for species of conservation concern often requires a balancing act between the short-term costs of direct mortality caused by fires and the long-term benefits of ensuring high-quality habitat. To reduce risk to threatened populations, land managers may need to adjust the frequency with which they burn sites and, likely, mitigate the short-term costs of prescribed fires by not burning during a species' life stages that may be especially sensitive to fires. Few, if any, studies have investigated burn regimes for butterflies in longleaf pine forests-a once dominant habitat in the southeast United States-despite a long history and frequent usage of prescribed burns in these ecosystems. We surveyed a recently discovered metapopulation of frosted elfin (Callophrys irus) butterflies residing in longleaf pine forest over seven years at sites across nine management units with differing fire return intervals and fire seasonalities. We observed dramatic population declines after burns, with no adults observed at some sites in subsequent years. Our analyses demonstrate that populations may need at least three to 4 years to recover, and that burns in the spring, when frosted elfin eggs and larvae are found on hostplants, should be avoided if possible. In fact, our model suggests that the largest spring-burned sites have fewer than 20% of the adult elfins the year following a fire than do sites burned in other seasons. Land managers seeking to conserve frosted elfins and other butterflies with similar life histories may need to burn at times of the year that reduce direct mortality and with fire return intervals that are longer than the one-to two-year intervals recommended by some for maximizing the diversity of the herbaceous understory in longleaf pine forests.

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1. The frosted elfin (Callophrys irus) butterfly inhabits landscapes that may be subject to frequent fire to be sustained. Frosted elfins pupate primarily in leaf litter, at the soil surface, or just below it, and may suffer high mortality rates when fires occur.Gathering better information on this source of mortality is critical to planning prescribed fire operations in a manner conducive to the long-term survival of the species.2. We buried lab-reared frosted elfin pupae (n = 61) at 0.75 cm (n = 31) or 1.75 cm (n = 30) below the ground and conducted two experimental fires that mimicked typical prescribed fires.3. Eighteen of 30 (60%) buried at 1.75 cm survived 4 weeks postburn; no pupae buried at 0.75 cm survived. Most (n = 17) of the pupae that survived successfully enclosed the following year. Surviving pupae encountered lower maximum temperatures and were exposed to shorter durations of above-lethal temperatures compared to those that died. 4. Our data demonstrate that high mortality rates can be expected due to fire, yet fire remains a critical tool for maintaining the habitat. Fire practitioners should mitigate losses by using ignition patterns and suboptimal burn conditions to reduce fire intensity, or burn in a mosaic pattern across the landscape to ensure enough survival to perpetuate frosted elfin populations.

New advancements in camera trap technology have led to wide-spread use in animal monitoring. In this study we tested whether modern self-contained camera traps could be used to identify small lepidopterans such as the frosted elfin (Callophrys irus). A vast majority of photographed lepidopterans, 76/81 (93.83%), were identifiable to family when moving relatively slowly across the camera’s field of view. Although no C. irus were observed, we were able to identify several species of lepidopterans including those of similar size as C. irus. We find that modern camera traps are adequate to sample small lepidopterans and may open new avenues to survey for small rare species such as C. irus over larger areas than typically possible with small field crews and short flight seasons.