Koalas continue to occupy their previous home-ranges after selective logging in Callitris - Eucalyptus forest

Abstract

The koala (Phascolarctos cinereus) is a charismatic, high-profile species whose conservation needs are commonly perceived to be incompatible with logging. However, koala biology and the results of chronosequence studies elsewhere suggest that this species may tolerate a degree of habitat alteration caused by logging. In this study, 30 koalas, five in each of six areas available for logging within a mixed white cypress pine (Callitris glaucophylla)-Eucalyptus forest in north-western New South Wales, were radio-tracked for one year during 1997-1998 to determine their movements, homerange sizes and tree preferences. Five months after the study began, three of these areas were logged selectively for sawlogs and thinnings of the white cypress pine, a tree that is important to koalas for daytime shelter. This removed about onequarter of the stand basal area, but the eucalypt component was unaffected. The remaining three areas were left undisturbed as controls. Radio-tracking continued in all six areas for another seven months. Koalas continued to occupy all or part of their previous home-ranges after selective logging, and home-range sizes remained similar between logged and unlogged areas. Home-ranges for both sexes overlapped and were ~12 ha for males and 9 ha for females. Koala survival and the proportions of breeding females were similar in logged and unlogged areas. The principal food trees of the koala were red gums, mainly Eucalyptus blakelyi and E. chloroclada, and the pilliga box (E. pilligaensis), none of which were logged in this study. These results suggest that selective logging for white cypress pine does not appear to adversely affect koala populations and that koalas may not be as sensitive to logging as previously thought. Further work is required to determine thresholds in the level of retention of koala food trees in logging operations. Koalas continue to occupy their previous home-ranges after selective logging in Callitris-Eucalyptus forest

Climate change and the koalaPhascolarctos cinereus: water and energy

“…In N.S.W., two recent studies have commented on the use by koalas of non-food species (Kavanagh et al 2007;Matthews et al 2007), with Kavanagh et al (2007) suggesting that there may be a relationship between the use of these trees and severe weather events. At other sites, such as St Bees Island, in central Queensland, tree use was attributed to social dynamics as well as tree characteristics (Ellis et al 2009).…”

Ecology and movement of urban koalas adjacent to linear infrastructure in coastal south-east Queensland

“…Home ranges and habitat use of koalas (Phascolarctos cinereus) have been widely studied throughout their distribution (Mitchell 1989;Hasegawa 1995;White 1999;Cork et al 2000;Ellis et al 2002;Thompson 2006;Kavanagh et al 2007;Matthews et al 2007). Home ranges are generally 1-50 ha (Cork et al 2000) although they are larger in some localities (Ellis et al 2002).…”

The Paradox of Euthanizing Koalas (Phascolarctos Cinereus) to Save Populations From Elimination

“…Days of extreme heat have been invoked as a threat to koalas in the Pilliga forests (Kavanagh and Barrott 2001;Kavanagh et al 2007) and anecdotal information suggests a substantial population decline occurred with the recent drought (Parnaby 2010 personal communication). Given that climate change scenarios for the western part of the koala's range suggest higher temperatures and less rainfall overall, and more extreme hot days each year, there is potential for the distribution of the koala to be significantly reduced permanently in New South Wales and in Queensland.…”

“…For example, while clearfelling will remove habitat, koalas may persist in selectively-logged forests (Kavanagh et al 1995;Kavanagh et al 2007). Thus the level of threat posed by logging is situation-specific and is determined by the appropriateness of the management regime, and adherence to its prescriptions.…”