Kangaroo Managment Plan - Territory and Municipal Services - ACT ...

ACT KANGAROO MANAGEMENT PLAN
Historical and oral accounts described kangaroo numbers in the ACT as being in ‘plague’
proportions in the latter part of the 1800s, when kangaroo and wallaby drives were carried out
and states introduced bounties. There is no way of determining what these densities were. In the
mid-1900s, most of the ACT was still in pastoral use and kangaroos were considered relatively
uncommon due to widespread shooting to reduce perceived competition with sheep, provide
food for dog packs, to reduce damage to fences and for recreation. From the 1950s, biological,
cultural and economic changes reduced the need, incentive and ability of ACT graziers to
control kangaroo numbers. The economic importance of rabbit fences declined rapidly after the
spread of myxomatosis. There were fewer farm labourers (therefore, fewer guns and dogs), more
intensive pasture improvement, rural land withdrawals and conversion of the land to leasehold
(KAC 1996a). Sharp increases in local kangaroo populations were noticed from the 1960s to the
1990s, especially in reserve areas, some of which border rural leases and provide a reservoir of
animals that can move out to graze on adjacent pastures.
The first credible estimate of kangaroo densities in the ACT was by prominent herbivore ecologist
Graeme Caughley in 1983 who visually estimated a density of 200 kangaroos per square kilometre
(2 per ha) at Tidbinbilla Nature Reserve, surprisingly close to the more rigorous later estimates. In
the 1980s and 1990s, Perry and Braysher (1986) estimated kangaroo densities in reserves and on
ACT rural properties for rental rebate purposes, from the density of faecal pellets.
Between 1995 and 1999, line transect methods were used to estimate kangaroo densities in
reserve areas and Googong Foreshores. These areas showed densities in the range from 1.9 to
3.7 per hectare (190–370 per km 2 ) (Freudenberger 1996; KAC 1997; Muranyi 2000; Nelson 1996).
In a survey of three reserve areas between 2001 and 2003, Fletcher (2006a) found densities in
grasslands between 4.5 and 5.1 per hectare (450–510 per km 2 ). These are among the highest
recorded in Australia and compare with almost 0.56 per hectare (56 per km 2 ) for a mix of eastern
grey and red kangaroos at Kinchega (Bayliss 1987) and 2.2 per hectare (220 per km 2 ) for eastern
grey kangaroos at Yan Yean Reservoir, near Melbourne (Coulson et al. 1999). Relatively high
densities have been recorded also in favourable environments such as in and around golf courses
e.g. 3.6 to 4.1 per hectare at Anglesea, Victoria (Catanchin 2005; Inwood 2006). Inside the 1.1 km 2
fenced area at Belconnen Naval Transmitting Station, kangaroo density was 5.6 per hectare before
a cull undertaken in 2008. At the Majura Training Area, in May 2008, the density reached 3.3 per
hectare over the whole site, including 5.3 per hectare in the grassland section (unpublished data,
Department of Defence).
The densities in ACT reserves are considerably higher than on ACT rural leases where culling
occurs. Between 1995 and 1997, densities of 0.39–0.59 per hectare (39–59 per km 2 ) (see Appendix
5) were estimated on ACT rural leases (KAC 1997) and provided evidence in support of the
arguments being put forward by rural lessees for culling. Densities on rural land in New South
Wales surrounding the ACT in 2003 and 2006, based on helicopter line transects methods, were
0.12 and 0.14 kangaroos per ha (12 and 14 per km 2 ) respectively (Cairns 2004; 2007). However,
helicopter line transect surveys underestimate kangaroo density compared to walked line transect
surveys (Clancy et al. 1997).
Examples of kangaroo density estimates for the ACT and elsewhere are shown in Appendixes 5
and 6.
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