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Between January 1981 and September 1997, goat mustering and aerial culling was conducted on
Mootwingee National Park and Coturaundee Nature Reserve, an area with high densities of goats
(Southwell et al. 1993). The goat control campaign was initiated as a general management strategy to
reduce the negative impacts of goats on native vegetation, aboriginal art sites and the endangered yellowfooted
rock-wallaby (Petvogale xanthopus). During this period a total of 42,516 goats were removed
(13,089 mustered, 29,427 shot). Between January 1988 and June 1995 it was possible to calculate
population indices for goats using aerial culling data; Ln(number of goats shotlminute flying time+l).
The study site was sub-divided into northern and southern blocks and population indices calculated for
each block. Linear regression equations were fitted to the population indices plotted across time. The data
suggest that despite the removal of considerable numbers of goats from both blocks of the study area
(1 1,601, northern; 10,035, southern), there was no detectable decrease in goat numbers over the 1988-
1995 period. For both blocks the slope of the regression line was negative and close to zero (-0.005,
northern; -0.0003, southern). The results indicate that the impact of mustering and shooting was shortterm
and that the re-invasion rate by goats into the area was very high. In areas of high goat density,
control measures need to be regular and conducted over a broad geographic area if goat numbers are to
be effectively reduced. No detectable increase was noted in the yellow-footed rock-wallaby population
during the period of intensive goat control.