The effect of forest management on endangered insects assessed by radio-tracking: The case of the ground beetle Carabus olympiae in European beech Fagus sylvatica stands

Beech forests are important for biodiversity conservation in Europe and studies to identify sustainable forest management practices are therefore required. The ground beetle Carabus olympiae Sella, 1855, is a large steno-endemic endangered alpine species with very restricted ranges. Its known range is only delimited in two beech forests in the western Italian Alps where beech wood is still harvested. Forty individuals were collected and radio-tracked in 2014–2015 in order to assess the effects of forest management on microclimatic conditions, microhabitat use and movements. Regarding microhabitat selection deadwood and tree bases were preferred, and were used as refuges during the daytime. Bare ground was not used. The length of the path travelled by individual insects was more variable and the tortuosity was lower in managed than in unmanaged stands, suggesting that management induced more constrained trajectories and variable distances. We concluded that logging may exert short-term negative effects on C. olympiae ground beetles. However, the preference for tree bases and deadwood suggests that forest management, concurrently, may also be beneficial, on the condition that: i) the coppice, which provides more suitable microhabitats, prevails over conversion to high forest, and ii) deadwood originating from cutting (branches and treetops) is properly accumulated.