Ecology of New Zealand's long-tailed bat (Chalinolobus tuberculatus) in exotic plantation forest

Abstract

Long-tailed bats (Chalinolobus Iiiberciilatiis), endangered endemic Vespertilionids, are present in plantation forests throughout New Zealand, but little is known of their biology within these continually changing mosaic habitats. Within the Central North Island native forest has largely been replaced by these planted forests, and consequently the persistence of long-tailed bats in this region may rely in part on their survival within plantations. As a result, this research began in Kinleith Forest, an exotic plantation, with the aim of better understanding bat biology there so that scientifically-based management plans could be formulated to protect long-tailed bats. Higher levels of bat activity were recorded within the plantation's Pinus radiata stands compared to the surrounding pasture and young regenerating native areas, indicating this plantation provides important habitat for bats. Highest activity levels were within the oldest forest stands, reflecting bats' use of these stands for roosting. Long-tailed bats used rare, ephemeral and poorly insulated roosts within stands near harvest age in the plantation. The use of roosts under peeling bark indicate that bats have more flexible roost selection criteria than expected, probably related to availability of such trees within plantations. Roosts were rare so populations were probably more limited than in other habitats, as indicated by comparatively high rates ofroost re-use, Iong periods of occupancy and small colony sizes. Roosts were Iost in clearfell harvest operations resulting in smaller roosting areas, and fewer roosts being used post-harvest. Clearfell harvest operations resulted in bats either moving into Iess familiar areas or contracting their home ranges, both of which reduce the likelihood of survival. Median colony size declined during the Ihree years of study, probably because of locally high levels of roost Ioss due to forestry operations and natural tree fall. Roost Ioss and small colonies that are reducing in size may cause locally ephemeral bat populations. This thesis concludes with recommendations for scientifically-informed management of long-tailed bats within plantation forests and the mitigation of effects of clearfell harvest on bats. The development of management plans based on these recommendations will best be achieved by collaborations between managers and researchers.