Exploration of mutual benefits between conservation efforts of the most critically endangered butterfly and regional agriculture/forestry industries ―The Nature Conservation Committee, The Lepidopterological Society of Japan―

<p>The lycaenid butterfly, Pithecops fulgens tsushimanus Shirôzu and Urata, 1957, which is distributed only in Tsushima Island, has become the most critically endangered of Japanese butterflies due to the impact on its habitats of overbrowsing mainly by Sika deer in recent years. We addressed the following three actions to conserve and increase the population of the endangered species: a) practical conservation and breeding activities in protection areas; b) search for additional protection areas; c) collaborative activity between conservation of the endangered butterfly and agriculture/forestry industries. In the conservation and breeding activities, the protection areas were improved due to environmental management developments and additional deer-proof fence construction. Floor vegetation, temperature/humidity and canopy openness of the protected areas were investigated in order to understand the environmental conditions. For future stock preservation and reintroduction of the butterfly, we also conducted an experiment on photoperiodism controlling overwintering and non-overwintering of the larvae, and the results indicated that some larvae most likely sense photoperiods from the 1st instar. In the search for additional protection areas, 30 sites, cultivation fields of shiitake mushrooms which the butterfly generally prefers, were investigated. Of the sites, 11 were deemed excellent habitats for the species. In the collaborative activity between conservation efforts and agriculture/forestry industries, our questionnaire survey revealed that many land owners and shiitake mushroom farmers were favorable to the conservation of this butterfly. They were also enthusiastic towards the commercial potential, such as promotional branding of mushrooms produced in designated conservation areas.</p>