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Using implanted radiotransmitters, we monitored body temperatures in five platypuses ranging freely in the Thredbo River in Australia's southern alps between April and October 1988, where the water gets as cold as any that a platypus is likely to encounter. Activity pattern showed a distinct daily cycle. No evidence of hibernation or even brief periods of torpor was found, all individuals maintaining body temperatures close to 32-degrees-C throughout the winter (mean+/-s.d., 32.08 +/- 0.75-degrees-C, range 29.2-34.6-degrees-C, n = 2237). No differences were found between the means or the variances of body temperatures of animals during day-time rest in stream-bank burrows and those during night-time foraging in winter at temperatures as low as 1.0-degrees-C.

This paper develops a hierarchical landscape approach for investigating how landscape structure influences the abundance of eastern grey kangaroos, red kangaroos and common wallaroos on properties in a partially cleared semi-arid woodland of Queensland. This approach is applied to examine the extent to which a mosaic of spatial factors at a hierarchy of scales influences kangaroo abundance at the property level. the level of management interest. The analysis concludes that the structure of the property habitat mosaic, coupled with pasture productivity, is the most important influence for each species. Access to water was not a limiting factor. although it may be important locally. Grey kangaroos prefer an even mosaic of all habitat types on properties with productive grass-dominated pastures. Red kangaroos are positively associated with run-on areas and large-shrub regrowth patches. reflecting their foraging preferences for forbs and short grasses and their ability to use more open habitats. Wallaroos have a clumped density distribution associated with a heterogeneous mosaic of open habitats interspersed with fragmented forest patches and small to medium-grained shrub-regrowth patches. The research. \+bile not replicated. identifies linkages between tree clearing practices at the property level and increased large kangaroo abundance in the region, These linkages have been previously overlooked in thc kangaroo Inanagement debare. Therefore. any tree clearing guidelines dt.\eloped at the propert) level need to be sensitive to key ecological processes influencing kangaroo populations at both the landscape and property levels. If not, the sustainable management of total grazing pressure (livestock plus kangaroos) and biodiversity conservation will never become a reality. Key words: kangaroos, landscape structure, landscape change, pattern, process, scale

As part of a large-scale monitoring program linked to the management of kangaroos in the South Australian pastoral zone, the western grey kangaroo populations have been surveyed annually with fixed-wing aircraft over the 15-years-period 1978–92. Western grey kangaroos are restricted in their distribution to the southern regions of the pastoral zone. During the period of the study, western grey kangaroo numbers showed no long-term trends, but did show some marked fluctuations, principally in association with a severe drought. Despite this, and unlike red kangaroos in the South Australian pastoral zone, no consistent, direct association between changes in western grey kangaroo numbers and antecedent rainfall could be demonstrated. The postulated reason for this is that most of the regional western grey kangaroo populations examined in this study were low-density populations at the edge of the range of this species. Outside of drought, these populations are likely to be limited by factors other than food, such as climate and unmodified resources in the form of suitable habitat. Also, because boundary populations may well only be maintained by constant loss and recolonisation, local extinctions associated with drought may result in extended delays in the re-establishment of populations in marginal areas. Over the period 1978–92, these populations were harvested commercially at annual rates of 5–25%, which were, on the whole, considered to be below the rates suggested to be maximum and sustainable.

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Density distributions of red and western grey kangaroos in the South Australian pastoral zone were determined for the period 1978-86. The habitat associations of these kangaroos were analysed using the densities on half-degree blocks, and information on landform and soil type, land use and degradation, vegetation, and climate. Red kangaroos were found throughout the pastoral zone, the highest densities being in the north-east. Western grey kangaroos were restricted to the southern parts of the pastoral zone. Higher densities of red kangaroos were associated with pastoral land use, with brown calcareous and red duplex soils, and with areas dominated by low bluebush shrublands. They were not particularly closely associated with areas dominated by mulga. Habitat associations of red kangaroos were different in drought years compared to non-drought years. Changes in density distribution during drought appears to have been due to the patchiness of rainfall. The relative effect of the drought was greatest in the northern part of the pastoral zone. Outside this effect, recent rainfall was found to be of only secondary importance to the overall density distribution of red kangaroos. Climatic factors appeared to be the major determinants of the density distribution of western grey kangaroos. Low evaporation and relatively high rainfall characterised areas with high densities of western grey kangaroos. As was the case with red kangaroos, habitat heterogeneity appeared to be an important requirement of western grey kangaroos. Also, habitat associations were different in drought and non-drought years. Despite this, as was the case with red kangaroos, recent rainfall was only of secondary importance to the overall distribution of western grey kangaroos.

Trends in numbers and changes in the distribution of feral goats in the South Australian pastoral zone (217300 km*2) during 1978-94 were determined by winter aerial surveys. Only the presence or absence of goats on sample units was scored between 1978 and 1988. On the assumption of a random distribution of goat groups, these indices were transformed to densities of goat groups. Between 1989 and 1994 actual goat numbers were recorded on each sample unit, allowing goat density to be estimated. Goats were consistently at their highest densities in the south-east of the pastoral zone, a region dominated by open mallee scrub and chenopod shrubland. Densities of goat groups fluctuated from a low in 1984, following a drought, to a peak in 1990, following above-average rainfalls, when there were an estimated 193700 +/- 29600 goats in the pastoral zone. This estimate is conservative because it is uncorrected for the visibility bias associated with sighting groups and undercounting their sizes. The estimate also excludes the Flinders Ranges for which a similar number of goats has been estimated.

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