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We studied the effects of logging history, topography, and potential insolation on the lower-elevation limit of existing spruce-fir forest in Great Smoky Mountains National Park (GRSM). Dummy-variable regression, analysis of variance, and classification trees were applied to environmental data within a geographic information system framework. The effect of logging history on the lower limit of spruce-fir depended on aspect. On north-facing slopes (270°-90°), the presence of spruce-fir was independent of both logging history and potential insolation. On south-facing sites (90°-270°), the elevation of spruce-fir was significantly higher (by 122 m) in areas that had been logged historically. Classification-tree models suggested an even greater logging effect, indicating that both the lower limit and the upper dominance zone of spruce-fir forest are, on average, nearly 200 m higher in historically logged landscapes. Presence of spruce-fir on south aspects was also significantly related to potential insolation, but the strength of this effect was not dependent on logging history. Classification-tree models, developed separately using data from logged sites versus unlogged sites, were used to estimate the current area of spruce-fir forest in the park expected under the hypothetical scenario that no spruce-fir had been logged (38,675 ha) versus the alternate scenario that it had hall been logged (11,727 ha). At present the area of sprucefir forest in the park is 21,242 ha. We found greater prevalence of spruce-fir on the Tennessee side of the divide on south aspects and historically logged sites, possibly due to greater occurrence of westerly winds and associated cloud cover.

The Duke of Burgundy butterfly (Hamearis lucina) has undergone severe declines over the last four decades. However, in recent years the UK population appears to have begun expanding again. This is likely to be due to beneficial management, although a warming regional climate may also have contributed to the resurgence of this spring-flying species. In this study, we investigated the effect of air temperature on the flight behaviour of adult male Duke of Burgundy butterflies. We also looked at the ability of adult males to behaviourally thermoregulate their body temperature and assessed their tendency to remain within small established territories. Increasing air temperature lead to a marked increase in the number and duration of flights associated with territorial behaviour but had no significant effect on other flights. This suggests that high temperatures are particularly important for sustaining energetically-demanding flights involved in territory defence and mate interception, which could impact the reproductive potential of Duke of Burgundy populations. We also found that butterflies had only a limited ability to regulate their body temperature behaviourally and may, therefore, be especially dependent on suitable environmental conditions to maintain the right temperatures for these flights. During observations, most males also remained confined to a few square meters within their territories, which could further restrict butterfly ability to thermoregulate by limiting relocation to other habitat types. However, we did find more males to leave the confines of their territories than expected from reports in previous studies. Our findings highlight the key role that warm, sheltered locations on reserves have in supporting the Duke of Burgundy. If this traditionally poor disperser is to take advantage of a warmer climate and extend its range North, a close network of such areas, appropriately managed, may be critical.

The Duke of Burgundy butterfly has undergone considerable range contractions across Europe and since the 1970s has lost around 84% of its former distribution in the UK. Despite its endangered status, the butterfly is understudied, with few papers directly investigating its habitat requirements. This limited research effort focusses on the larval life stage, with relatively little being known about the adults of the species. In this study, we investigated the habitat usage of both adults and larvae of the Duke of Burgundy. Fieldwork was carried out in association with the Bedfordshire, Cambridgeshire and Northamptonshire (BCN) Wildlife Trust on their Totternhoe Quarry Reserve in Bedfordshire. Using data collected over the course of a decade, we performed the first long term distribution analysis of the species and we identified habitat attributes associated with long-standing abundance hotspots of both adults and larvae on the reserve. We found both life stages to be conserved in their range, remaining in the same small areas of Totternhoe Quarry year on year, with adults often being more restricted in their distribution than larvae. Sheltered locations were important for both life stages, but small differences in habitat preference, such as slope and aspect, were also identified. These results emphasise the need to target management towards both life stages of the Duke of Burgundy, as supporting the larvae alone may not result in suitable environmental conditions for the adults.

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