Food tree selection by an arboreal marsupial: Implications for timber harvest

Abstract

ContextThe Yellow-bellied Glider (Petaurus australis) is a vulnerable arboreal Australian marsupial that is threatened by logging. Trees used for sap feeding (sap trees) are a critical habitat requirement of the species, yet no harvest retention policy exists in the southern part of its range in Victoria, Australia. Yellow-bellied Gliders are extremely selective in sap tree use with some trees used far more frequently than others. AimsWe aimed to determine the tree species used and identify characteristics influencing intra-species tree selection for sap feeding by Yellow-bellied Gliders in the Highlands - Southern Fall Bioregion of Victoria. MethodsSap trees were located at each of 12 sites. We measured nine characteristics related to photosynthetic capability, microsite, and habitat for sap trees and the nearest tree of the same species without Yellow-bellied Glider incisions (reference tree). For sap trees, we measured 11 incision-related variables. Permutational Multivariate Analysis of Variance was conducted to identify distinguishing characteristics of sap trees. Generalised Linear Mixed Modelling was used to determine the influence of tree characteristics on abundance of incisions on a tree. Key resultsFive of 24 tree and tall shrub species present across the 12 sites were used for sap feeding. All five species were Eucalyptus. Within the tree species used, Yellow-bellied Gliders selected for trees that were larger, had wider crowns and occupied dominant and co-dominant canopy positions. ConclusionsYellow-bellied Gliders are highly selective of trees used for sap feeding. Although primarily selecting larger more dominant trees for sap feeding, lack of clear identifying characteristics means that identifying and retaining preferred sap trees in logging coupes must rely on site surveys for incisions on trees.