Rapid Uptake of Nest Boxes by the Endangered Greater Glider (Petauroides volans)

Abstract

The loss of hollow-bearing trees poses a critical threat to hollow-dependent species. Nest boxes as supplementary habitat have emerged as a conservation tool for certain species, but their use in providing habitat for Southern Greater Gliders (Petauroides volans), a heat-sensitive and hollow-dependent species, remains limited. This study investigates the uptake and use of nest boxes designed specifically for Greater Gliders in a postfire environment. Thirty nest boxes were installed at a site that experienced moderate to severe fire during the 2019/2020 bushfires. Four different nest box designs were investigated for their thermal properties, colonisation rates and usage patterns. The time for a nest box to be used by a Greater Glider was rapid, at an average of 34 days after time of installation. Continuous camera monitoring over the course of a year revealed 100% colonisation, with gliders consistently using nest boxes across seasons regardless of nest box design. We found that nest box design influenced internal temperatures, and the best performing nest box design (constructed of wood and without foil insulation) was on average 1.99°C cooler inside than ambient temperatures (on warm days equal to or above 20°C). In comparison, natural tree hollows in use by Greater Gliders at the study site, had a much greater thermal buffer (on average 7.32°C cooler than ambient temperatures on warm days). Observations of Greater Gliders sitting outside at the entrance hole of nest boxes during the day was linked to warmer temperatures, indicating Greater Gliders likely exited nest boxes to thermoregulate. This study identified a rapid acceptance of nest boxes by the Greater Glider and offered insights into the role of nest boxes as supplementary habitat to assist population recovery following the loss of hollow-bearing trees.