Re-assessment of chainsaw-carved hollows and animal use seven years after installation

ABSTRACT Carved hollows have been incorporated into wildlife management plans to mitigate the loss of tree hollows in the landscapes, but little is known about their longevity, maintenance schedules, and long-term use by hollow-dependent fauna. We assessed chainsaw-carved hollows (n = 16) in live and dead host-trees, seven years after they were installed in a south-eastern New South Wales forest in 2015. We investigated: (1) current status of live and deceased host-trees; (2) carved hollow and faceplate condition and functionality; and (3) current animal species occurrence. We found that no host-trees failed due to carved hollows. Overall, 69% of hollows remained functional, of which 82% showed signs of inhabitation and 55% were currently used by four species: Feathertail Glider Acrobates pygmaeus, Brown Antechinus Antechinus stuartii, Sugar Glider Petaurus breviceps, and White-throated Treecreeper Cormobates leucophaea. Within the functional hollows, all live host-trees had woundwood development, faceplate shrinkage averaged 10mm, signs of faceplate decay were observed in 9%, and water ingress occurred in 45% of hollows. One hollow was waterfilled and was actively being used as a ‘water station’, we recorded the highest diversity of fauna visits to this carved hollow. Immediate maintenance was required for 23% of hollows, while a further 38% may require maintenance in the future (∼5 years). These findings demonstrate the longevity of carved hollows in both live and dead trees in the medium term (5–10 years) and their continued use by hollow-dependent fauna. However, we predict a maintenance schedule for ∼50% of hollows at ∼10 years post installation.