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The home range, reproductive condition and warren and habitat use of reintroduced female burrowing bettongs was compared within two enclosures in the Arid Recovery Reserve at estimated densities of 2.75 and 7.5 bettongs km–2. Bettongs at both densities exhibited similar behaviour, with females using an average of 2.7 warrens over six months and home ranges averaging 29 and 35 ha in the low- and high-density enclosure respectively. All five female bettongs studied in the low-density enclosure were carrying pouch young at the beginning and end of the six-month study but only one of the five females in the high-density enclosure was carrying pouch young after six months. Higher food availability may have accounted for the higher reproductive effort and slightly smaller home ranges observed in the low-density enclosure. Female bettongs at both densities favoured dune habitat over chenopod swales and all burrows were in dune habitat. Although some differences in reproductive output were observed, it is likely that densities are not yet high enough to cause significant behavioural changes.

Detailed studies of how endangered species use their environments at varied habitat scales are crucial if they are to be conserved and managed effectively. In this study, we used spool-and-line tracking to investigate the microhabitats used by the brush-tailed bettong (Bettongia penicillata) and the burrowing bettong (B. lesueur), two species with geographical ranges that have been dramatically reduced since European settlement in Australia. The study was carried out at Scotia Sanctuary, in semiarid western New South Wales, where both species have been recently reintroduced. The nocturnal movements and foraging of bettongs were associated with sites containing more canopy cover (mean 10–25%) than was available on average (0–10%). Models generated to predict the probability of bettong movements or activity points showed positive correlations with ground vegetation cover and ground vegetation height. Other microhabitat components of varying importance, including sand cover, litter cover, litter depth, crust cover, and distance to shrub/tree, were incorporated into these models. Species comparisons indicated that, although slight differences occurred in the way each species moved through the habitat, both species foraged in areas with similar microhabitat characteristics. While the models should have broad utility for the selection of favourable habitat for future release sites for B. penicillata and B. lesueur, further studies of diet and food availability are recommended to refine them further.

A 'stunning' technique, combining a rifle shot with spotlighting and hand netting was used for the live-capture of southern hairy-nosed wombats. A successful stun was defined as a rifle shot that resulted in the temporary deafening and disorientation of a wombat. When combined with spotlighting, this technique enabled catchers with nets to approach the wombat undetected to secure an easy capture. Environmental factors (temperature, humidity, dew point, light and wind) were examined in order to determine the optimal conditions for the use of this capture procedure. In all, 558 shots were fired, resulting in ~25% of successful stuns. Stunning was primarily affected by temperature and humidity in a normally distributed manner. Stunning was greatest between 12°C and 18°C with a success rate of 40–51%. At temperatures either side of this significantly fewer stuns were achieved, and below 6°C or above 24°C no successful stuns were recorded. Likewise, stunning worked best at humiditys of 70–90%, declined when humidity was >90% and did not work at all at a humidity of 40% or less. Together, temperature and humidity data suggest that air density, for which these parameters are correlates, may be the key component in the success of this capture technique. Variation in stunning success resulting from changes in temperature and humidity may affect either the frequency spectrum of the sound created by the shot or perhaps the manner in which the eardrum receives the sound. Other factors, including dew point and light, also varied significantly with stunning, but were considered of less importance. Whatever the controlling factors, it was clear that stunning, in combination with spotlighting and netting is a rapid, highly effective, and potentially much less stressful method of capturing southern hairy-nosed wombats than the methods that have been used previously.