Effects of land-cover history on the occurrence of Luciola cruciata in the southern Tama region of Tokyo, Japan

Abstract

Luciola cruciata is a common firefly species that has cultural significance in Japan, and it is often reintroduced in regions where its numbers have diminished. It is therefore important to determine appropriate reintroduction and/or population-reinforcement strategies for the conservation of L. cruciata. In this study, we used historical land-cover data to evaluate the landscape conditions needed for the establishment or maintenance of L. cruciata populations. We surveyed the presence or absence of L. cruciata in the southern Tama region of Tokyo, and used a statistical model based on Akaike's information criterion (AIC) to analyse the association thereof with land-cover history. Among the parameters included in the model, only the presence of a current open-water area was positively correlated with the presence of L. cruciata (AIC = 271.11). A slightly lower AIC value (270.44) was obtained for a land-cover-history model that included current open-water area, 1980s' forest area, and 1960s' farmland area; all explanatory variables in the model were positively correlated with the presence of L. cruciata. The results imply that the suc- cess of reintroduction and/or reinforcement of L. cruciata populations may depend on the land-cover history. The findings of this study will be helpful for identifying regions suitable for establishing or maintaining L. cruciata populations, which is important for the conservation of this species in Japan.