Habitat preferences of Papilio alexanor: implications for habitat management in the Italian Maritime Alps

Papilio alexanor is a threatened European butterfly species listed in the Annex IV of the Habitats Directive and in the Appendix II of the Bern Convention, also considered extremely vulnerable to climate change. According to some projections (e.g. BAMBU, a scenario of moderate climate change), it would be expected to lose 63% of its European climatic niche by the year 2050 and 77% by 2080. The few remaining populations are expected to become concentrated in the Maritime Alps. In 2009 and 2010, we studied probably the densest P. alexanor population occurring in the Italian part of this area. It occurs in a series of dry xerothermic grasslands, also partially occupied by an abandoned limestone quarry, where the larval food plant is Ptychotis saxifraga. Females lay eggs in July, choosing patches where the food plants are higher and more abundant. The habitat preference, conservation status and survival of the early instars larvae of P. alexanor have been investigated to suggest conservation strategies for this species in the Italian Maritime Alps.