Koalas and climate change: a case study on the Liverpool Plains, north-west New South Wales

Abstract

Koalas Phascolarctos cinereus are specialised, folivorous arboreal marsupials that do not go into torpor, fly, or shelter in hollows, and lack any ready means of avoiding weather extremes. This makes them valuable candidates to study impacts of climate change. This paper draws on our field study of koalas in Gunnedah in northwest New South Wales (NSW), to not only examine this proposition, but to progress to the next step of considering how we, as koala managers, can adapt our strategies to help the koala population cope with predicted climatic changes. The koala already faces a powerful set of threats, such as loss of habitat and fragmentation of what remains, disease, fire, and the impact of losses from dogs and vehicles. Climate change will compound these issues, accelerate adverse changes and demand a reappraisal of our approach to koala management. The koala is not unique in this predicament, but it is symbolic of the impact that can be expected on a wide range of species.

Conserving koalas: A review of the contrasting regional trends, outlooks and policy challenges

“…The population neighbouring the Gunnedah township has been increasing since the 1980s, but declined in 2009 due to drought and a severe heatwave, with the remaining population showing a higher prevalence of Chlamydia due to sustained stress of drought and heatwaves (Lunney et al, 2012a). Proposed mining for coal seam gas or coal in the Pilliga and Liverpool Plains has the potential for adverse impacts on the koala population.…”

“…Increased concentration of CO 2 in the atmosphere will lower the nutritional quality of eucalypt food resources (Lawler et al, 1997;Moore and Foley, 2005;Hovenden and Williams, 2010;Lunney et al, 2012a). This was one of the factors determining the IUCN's (Johnson et al, 2009) listing of the koala as highly vulnerable to climate change.…”

The challenge for koala conservation on private land: koala habitat use varies with season on a fragmented rural landscape

“…In 2006, the koala population of the Liverpool Plains, north‐western New South Wales (NSW), Australia, was identified as one of the only koala populations in NSW to be increasing in occupancy (Lunney et al ., ). More recent surveys identified a declining koala population within this region (Predavec et al ., ) under the cumulative threats from climate change, habitat loss and fragmentation and chlamydiosis (Lunney et al ., ; McAlpine et al ., , ). Multiscale studies of koala presence in other regions have found that there is no single spatial scale at which landscape metrics have the strongest effect on koala presence (McAlpine et al ., 2006a,b, ; Januchowski et al ., ; Smith et al ., 2013a).…”

“…It is a specialized arboreal folivore that feeds predominantly on Eucalyptus and Corymbia species. Its highly specific diet varies within regional areas due to variation in local soil characteristics, tree structure, leaf water and chemical content (Moore et al ., 2004b; Lunney et al ., ; Crowther et al ., ). Resources and habitat quality are major influences on population persistence and are particularly important for habitat specialists, such as the koala (Smith et al ., 2013b).…”

Use of expert knowledge to elicit population trends for the koala (Phascolarctos cinereus)

“…In more recent times, indirect threats from urbanization (Dique et al ., ), disease (Wan et al ., ; Jobbins et al ., ; Polkinghorne et al ., 2013), dogs, motor vehicle collisions (Rhodes et al ., , ) and fire have become major threats to the koala's survival (Dique et al ., ; Lunney et al ., , Commonwealth of Australia, , ). Now, climate change (Gordon et al ., ; Adams‐Hosking et al ., , ; Seabrook et al ., ; Lunney et al ., , ) is an additional threat. Knowledge of the status of koala populations across its geographical range is needed to plan for conservation and management actions (Commonwealth of Australia, ).…”