Mountaintop refuges and causes of distribution limits for Antechinuses in Queensland

Date: 28, Sep, 2021
Author(s): Andrew Baker   Diana Fisher   Rachael Collett  

There are several antechinus species restricted to mountaintops in eastern Queensland, including two species listed as Endangered. Using camera and pitfall trapping surveys designed in 2017, we conducted a field study of several species of antechinus that are of conservation concern, across four Queensland national parks. We wanted to find out whether these species’ distributions are limited to these montane habitats because of recent environmental change or their evolutionary histories. We also investigated whether mountaintops could be refuges from predation or competition with other antechinuses; and if rainfall was a likely driver of their limited distributions and population densities. We found that antechinus population densities were directly linked to climate – particularly rainfall patterns – and each species’ evolutionary history. Winter rainfall increases the abundance of insect prey, which means that antechinuses are in better condition for breeding in late winter and early spring. The most important conservation action for these species is therefore to maintain the condition of their current habitats to prevent any further restriction of their current ranges and abundance. However, predicted lifting of the cloud base under climate change, increases in frequency and intensity of droughts, heatwaves and severe fires are likely to severely impact food supply at critical times of year, and habitat suitability. Effects of climate change on the habitat of the black-tailed dusky antechinus in particular will be especially difficult to counteract.