Future of the Greater Glider (Petauroides volans) in the Blue Mountains, New South Wales

Abstract

In a previous paper, we investigated whether the Greater Glider (Petauroides volans) is declining in Blue Mountains local government area and, if so, the factors responsible. In this paper, we reanalyse the data, replacing elevation (used as a proxy measure of climatic conditions) with temperature and rainfall estimates based on climatic modelling. The Greater Glider remains relatively common at higher elevations but has declined at lower elevations. In the 1980s, it occurred in similar abundance at all elevations, but in 2015-16 it was seven times more abundant above 500 m than below and could not be detected at 7 of 20 study sites in known habitat. Three variables accounted for most of the variation in abundance between sites: a negative relationship with mean annual temperature (31% of the variation) and positive relationships with mean annual rainfall (20%) and time since fire (14%), suggesting that the decline is linked to climate change, especially increasing temperature. We found no evidence that an alternative explanation, an increase in owl predation, was having a significant impact. The situation has worsened since our study, with a disastrous bushfire season in 2019-20 heralding a likely drastic change in the fire regime under climate change. The future prospects of the Greater Glider are looking increasingly bleak.