Yellow-footed Rock Wallaby Husbandry Manual - Marsupial and ...

HABITAT USE
A generalized diet, continuous breeding and embryonic diapause (see Reproduction section)
allow yellow-footed rock wallabies to exist in extreme conditions in their arid and semiarid
rocky outcrops (Pope et al, 1996). The presence of rock wallabies can be detected by the high
gloss which their feet give to the rocky floors of the caves in which they live as well as by their
droppings, which are elongated with pointed ends and not round as are other wallaby's pellets
(Ride, 1970).
The colony size can range from just a few animals up to 200 individuals or greater (S. Lapidge,
pers. com.). Colony density can be from 1.0 per square km up to 22.8 and even 29.1 per square
km (Lim et al, 1987). Although most activity is in the late afternoon or evening, rock wallabies
can be seen sunning themselves during daylight hours if the temperature is not too high.
Otherwise, they seek the shelter of the caves and outcroppings (Ride, 1970).
Home range is defined as the area in which an individual spends over 90% of its time. These
usually include a number of rock piles and a water source, although as stated, this presence of a
water source has been disputed with recent findings (S. Lapidge, pers. com.). The center of
activity, or core area, refers to the area in which an individual can be found 50% of the time
during the same period (Lim et al, 1987).
In a study done at Middle Gorge in 1981, the mean home range of males was found to be 168.8
hectares in winter and 210 hectares in summer. Females were found to have mean home ranges
of 164.3 hectares in winter and 134.3 hectares in summer. There was also overlap in home
ranges between individuals of both sexes during all seasons. The mean overlap was 58.13% of
the individual's home range in winter and 58.59% in summer (Lim et al, 1987). These results
were similar to homes ranges of 150-200 hectares for both sexes stated by Maynes in 1989 and
130-210 hectares, depending on the season, found by Steven Lapidge (pers. com.).
Studies done by Andrew Sharp indicate that the Queensland subspecies (Petrogale xanthopus
celeris) have home ranges of 20-40 hectares as compared to the 160-210 hectares home ranges of
the South Australian species. These results suggest that the South Australia habitat is more
marginal, requiring a larger area of land to meet dietary needs (Sharp, 1994).
The 1981 Middle Gorge study showed that activity cores was found to be the same for both
sexes in winter (27.5 for males; 27.59 for females). However, activity cores in the summer varies
greatly between the sexes. Females were found to occupy cores of an average 25.4 hectare, very
little difference from their winter activity. The males, however, greatly increased the size of their
core to an average 41.45 hectares (Lim et al, 1987).
The above observations suggest female dominance over males for choice in selecting resting
sites. This allows females to occupy prime forage and refuge sites, thus curtailing their need to
travel in the hot summer months. This also supports a theory of greater stability of the female
population (Lim et al, 1987). Females were also found to be more effectively able to defend
important refuge areas than males and also appeared to have a higher survival rate (Robinson,
1994).
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