The Vertebrate Fauna of Jenolan Karst Conservation Reserve: Final

BRUSH-TAILED ROCK-WALLABY PETROGALE PENICILLATA
EPBC Act: Vulnerable TSC Act: Endangered Priority in Area: Highest
Brush-tailed rock-wallaby. Photo © N.
Williams
Brush-tailed rock-wallaby. Photo © A.
Faulkner
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Occurrence in the Survey Area
Rare resident. Brush-tailed rock-wallabies occurred at JKCR
prior to European settlement. Declines were first noted as early
as 1899 (Eldridge et al. 2004). A semi-captive colony was
established which eventually became over-abundant. The fence
was removed in 1984 in order to let animals disperse naturally
and relieve grazing pressure. Between 1985 and 1992 the
population crashed to seven individuals (Eldridge et al. 2004).
Intensive fox baiting now occurs on the reserve to minimise the
impacts of foxes. The population has been supplemented with
captive bred individuals and animals sourced from different
populations to increase genetic diversity. Currently the
population remains small, though growing, and is estimated to
be 40 individuals (D. Ashworth pers. comm.). During the current
survey, brush-tailed rock-wallabies were recorded around the
Grand Arch, Nettle Cave and Arch Cave, with scats recorded
from far inside some of these caves.
Regional Conservation Significance
The population at Jenolan is part of the ‘central ESU’
(Evolutionary Significant Unit) of the brush-tailed rock-wallaby.
The central ESU is the most fragmented in NSW, and all sites
are of very high conservation significance (DECC 2008c). Within
the region there is ample habitat for the brush-tailed rockwallaby,
and approximately 70% of this habitat falls within
conservation reserves (DECC 2007). However, habitat is now largely unoccupied by brush-tailed rockwallabies
with serious threats acting both on and off reserve. It now exists in very few small, isolated,
inbred and often declining populations, almost all of which are the target of intensive site-based
management. JKCR is part of the NSW FoxTAP and is closely monitored and managed under that
program. The brush-tailed rock-wallaby population at JKCR is the most robust of the central ESU
metapopulations and hence of very high conservation significance. The loss of even a single individual
is significant.
Threats in the Survey Area
Within JKCR, the ongoing threats to this species are predation by foxes, dogs and possibly cats;
competition with goats, deer, pigs and rabbits; and
inbreeding and isolation (DECC 2008c, Eldridge et al.
2004). Additional threats that may be problematic are
roadkills, lead poisoning, tourist interactions and weeds.
Roadkill may be an emerging problem as the brush-tailed
rock-wallaby population increases, especially given the
proximity of the colony to Jenolan Caves Road and the
high traffic volumes. The accumulation of lead within the
Grand Arch (from electrical installations) in old brush-tailed
rock-wallaby shelter sites may result in poisoning if
wallabies begin to use them (A Musser pers. comm.).
Interactions with tourists may lead to tameness, the
reliance on humans for food, malnutrition and disease
(e.g. lumpy jaw) as well as increased roadkill and
depredation. Riparian weeds, particularly, periwinkle,
occur densely along the Jenolan River (downstream from
Blue Lake) and may limit the ability of brush-tailed rockwallabies
to forage and disperse into these areas (C.
Barker pers. comm.).
The Vertebrate Fauna of Jenolan Karst Conservation Reserve