Changes in bat activity over 10 years in silviculturally treated wet sclerophyll forest

Abstract

A range of silvicultural treatments are applied to timber production forests, resulting in varied vegetation structural complexity. We compared the bat assemblage across three silvicultural treatments (unlogged forest, unthinned regrowth and thinned regrowth), two locations (on and off track) and three time periods (pre-thin, plus one and six years post-thinning) in wet sclerophyll forests, with treatments implemented at a small catchment scale. Linear edges provided important habitat for bats as total bat activity was substantially greater on tracks than off tracks, especially in unlogged and unthinned regrowth forest. Bat activity off track was greater in unlogged areas than in thinned and unthinned regrowth. Activity and species richness off track were greater in thinned than unthinned regrowth, but the time by treatment interaction was not significant for activity, indicating this difference cannot be ascribed to thinning alone. Thinning also led to a species composition that more closely resembled unlogged forest than unthinned regrowth. These patterns in bat activity across silvicultural treatments in wet sclerophyll forests were broadly consistent with other forest types, but subtleties, such as a subdued response to thinning, requires more replication to resolve. Nevertheless, differences between forest types need to be considered when developing management strategies.