Summary 1.The interface between thermal biology and foraging mode has attracted little scientific attention, but may be crucially important to the biology of ectothermic predators. Slip & Shine (1988c) suggested that the ability of large heavy-bodied snakes to ambush nocturnally active mammals relied on the snakes' control of cooling rates through their thermal inertia (via body size and postural adjustments) and microhabitat selection. 2. We tested assumptions underlying this hypothesis, using Diamond Pythons (Morelia s. spilota) from southeastern New South Wales. Our laboratory studies confirmed that larger body sizes and coiled postures significantly retarded cooling rates, and that body temperature affected the snakes' ability to detect potential prey items. 3. The magnitude of these effects on cooling rates was great enough to extend the time period substantially over which an adult Diamond Python, lying in ambush in a suitable microhabitat, would be able to detect and capture nocturnally active prey. For example, the times taken for pythons to reach thermal equilibration under our experimental conditions (cooling from 33 to 12°C) were < 1 h for hatchling pythons regardless of posture, 1 h for outstretched juveniles, 2 h for coiled juveniles and outstretched adults, and almost 8 h for coiled adults. 4. The high rates of cooling of juvenile pythons, even when they are tightly coiled, may force them to rely upon diurnally active prey rather than crepuscular or nocturnal species.

This study used ecological criteria to evaluate systematically the conservation status of all mammals, birds, reptiles and frogs in New South Wales. The outcome was an official schedule of endangered fauna as defined under the New South Wales National Parks and Wildlife Act 1974 as amended by the Endangered Fauna (Interim Protection) Act 1991. The work was modelled on the study by Millsap et al. (1990) which scored a range of biological variables and used expert opinion to determine priorities for conservation. The listing was undertaken by a statutory Scientific Committee and the results provided the first baseline status list for all species in New South Wales. Of the 883 faunal species (including 10 Lord Howe Island subspecies) identified in the state, 233 (26%) were recognized as endangered. Of these, 40 are considered to be extinct in New South Wales. Mammals constituted the worst affected group, with 77 (59%) of the 130 species recorded as endangered, of which 27 species are recorded as extinct in the state. The assessment of the New South Wales fauna also found that adequate ecological information exists for only 6% of the state's species. The outcome of this study not only provided the first official list of the endangered fauna of New South Wales and explained the methods and reasons for listing or excluding each species, but also furnished new material, ideas and directions for programmes to conserve the state's fauna.

The aims of this study were to identify common ecological patterns among threatened fauna in New South Wales, and to identify priority areas for research and management by determining which regions and habitats contain high numbers of threatened fauna. Threatened and non-threatened fauna were taken from the listings of Lunney et al. (1996, 1997). Species were categorized into weight classes, diet groups, habitats and regions and by level of knowledge available about them. All regions and habitats of the State contain threatened species. The northeastern region of New South Wales contains the greatest number of threatened species but the western region has suffered the most extinctions, especially of mammals. Species that historically inhabited a greater number of regions are less likely to be currently threatened or to be extinct than those with restricted distributions, and large species are more likely to be threatened than smaller species. The best predictors of a threatened mammals species were seeds and vegetation in the diet, heavier body weight, and ground-dwelling, burrowing, and rock pile/cave-dwelling habits. The Critical Weight Range (35?5 500g), although strongly associated with extinction of non-volant mammals, was not the most important predictor. Lord Howe Island held the highest proportion of threatened and extinct birds. Factors showing the strongest associations for threatened birds were carnivory, large size, and distribution in the southeastern region. The most poorly-known region for birds was the north-east, and the least known habitat was shrubland (including mallee, heath and chenopod shrubland). The status of reptiles was poorly known in all regions, especially the western region. Frogs were also poorly known in all regions. Frogs were most at risk if they were large, inhabited closed forest or occurred in the central or northeastern region. The study further revealed little association between particular ecological attributes and conservation status. This indicates that there are complex and pervasive threats affecting the status of New South Wales fauna. Research and management priority status could be argued for all regions and most habitats in the State, but the western or northeastern regions may face the most problems depending on the criteria used (e.g., past extinctions, number vs proportion of threatened species). Further, the conservation status of birds, reptiles and frogs is in particular need of attention from researchers.

Any attempt to enhance rock lobster production by increasing survival after settlement, or by ongrowing or outplanting young juveniles, requires knowledge of the shelter preferences of young juveniles. For juvenile Jasus edwardsii in the wild these are not well known. Information available suggests that juveniles up to c. 35 mm carapace length (CL) occupy shelters that generally conform closely to their body dimensions but that larger juveniles use shelters of more variable dimension, often much larger than their body size. We investigated mainly physical factors important in shelter choice by 15-59 mm CL (c. 2-24-month-old juveniles) in laboratory tank experiments. In overnight tests, all sizes of juvenile lobster chose to occupy holes (shelters with sides) over open horizontal gaps. Preference for open horizontal gaps versus horizontal crevices (where the height reduces from a maximum at the mouth to zero at the opposite end) was much less clear-cut; choice varied according to lobster size. For the number of entrances into holes, there was evidence for an ontogenetic shift in preference, small lobsters preferring two openings over one, whereas those >30 mm CL (c. 9 months old) preferred one over two. For lobsters <40 mm CL, the hole size and gap size preferences revealed were generally consistent with the field evidence for J. edwardsii in that there was a close and proportional relationship between lobster size and shelter size; what differed was that the open gaps chosen in the M04064; tanks by the smallest lobsters (15-19 mm CL) were larger than the holes used in the tank experiments and 30-50% larger than those reportedly used in the field. For lobsters >40 mm CL, the holes and gaps chosen in the tanks were generally larger and more variable in size, as in the field.

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