Home range, habitat selection and diet of foxes (vulpes vulpes) in a semi-urban riparian environment

Between 2000 and 2002 the home range, habitat selection and diet of foxes were examined in the Dandenong Creek Valley, Melbourne, Australia. The mean home range was 44.6 ha (range 19.2–152.6 ha). A significant selection towards blackberry and gorse used as diurnal shelter was found during the day with an active avoidance of less structurally complex vegetation types. Although there was obvious selection of certain habitats, the diet of the foxes was highly general and opportunistic and thus offers little potential as a factor to manipulate in order to reduce fox abundance. Given the strong preference for blackberry and gorse as a shelter resource, a habitat-manipulation strategy is suggested whereby patches of blackberry and gorse are removed and replaced with less structurally complex vegetation. Such a strategy has the potential to influence the density of foxes in semi-urban riparian environments such as those discussed in this study.

No outbreeding depression at a regional scale for a habitat-forming intertidal alga with limited dispersal

Hormosira banksii is distributed throughout southern Australasia, but dispersal of propagules is thought to be limited. In the present study, the hypothesis that outbreeding depression occurs in H. banksii was tested by assessing fertilisation success and early development of embryos in crosses between populations at local to regional spatial scales. Hierarchical experiments were conducted at three spatial scales with nesting present within each scale: small scale (within a rocky shore population), intermediate scale (regions separated by 70 km) and large scale (450-km separation between two states: Victoria and Tasmania). In each experiment, eggs and sperm were crossed within and between each population located in the spatial scale of interest. There were no consistent patterns of variable fertilisation success and subsequent development within a population or at different spatial scales. It was concluded that outbreeding depression is not detected in analyses of fertilisation success or early development processes in H. banksii. The results suggest one of the following to be likely: (1) H. banksii is capable of longer distance dispersal than previously considered, thus maintaining gene flow between distant populations, (2) gene flow is restricted by limited dispersal, but populations have not been isolated for a sufficient length of time to cause genetic divergence or (3) outbreeding depression is manifested as effects on later life-history stages.

Distribution and habitat requirements of the Yellow-Footed Antechinus Antechinus flavipes at multiple scales: a review

This review synthesises present knowledge of the distribution patterns and habitat requirements of the Yellow-footed Antechinus Antechinus flavipes. Factors influencing the distribution of A. flavipes are examined at several spatial scales ranging from the broad climatic conditions prevalent over the species’ entire range to the characteristics of nest sites used by individual animals. Analysis of the literature suggests that: 1) at the broad-scale, A. flavipes distribution is largely determined by warm, dry climatic conditions, the distribution of dry forests and woodlands and competition with closely related species; 2) at the landscape-scale the determinants of A. flavipes distribution are largely unknown, although initial investigations suggest some tolerance of fragmented landscapes; and 3) at a local-scale the distribution of A. flavipes is largely determined by the presence of large diameter trees, tree hollows, coarse woody debris, rocky crevices and leaf-litter. Directions for future research are suggested throughout the review.

The influence of patient complexity and nurses` experience on haemodynamic decision-making following cardiac surgery

Critical care nurses’ haemodynamic decision-making in the immediate postoperative cardiac surgical context is complex. To optimise patient outcomes, nurses of varying levels of experience are required to make complex decisions rapidly and accurately. In a dynamic clinical context such as critical care, the quality of such decision-making is likely to vary considerably. The aim of this study was to describe variability of nurses’ haemodynamic decision-making in the 2-hour period after cardiac surgery as a function of interplay between decision complexity, nurses’ levels of experience, and the support provided. A descriptive study based on naturalistic decision-making was used. Data were collected using continuous non-participant observation of clinical practice for a 2-hour period and follow-up interview. Purposive sampling was used to recruit 38 nurses for inclusion in the study. The quality of nurses’ decision-making was influenced by interplay between the complexity of patients’ haemodynamic presentations, nurses’ levels of cardiac surgical intensive care experience, and the form of decision support provided by nursing colleagues. Two factors specifically influenced decision-making quality: nurses’ utilisation of evidence for practice and the experience levels of both nurses and their colleagues. The findings have implications for staff resourcing decisions and postoperative patient management, and may be used to inform nurses’ professional development and education.

A Complexity Based Model for Quantifying Forensic Evidential Probabilities

An operational complexity model (OCM) is proposed to enable the complexity of both the cognitive and the computational components of a process to be determined. From the complexity of formation of a set of traces via a specified route a measure of the probability of that route can be determined. By determining the complexities of alternative routes leading to the formation of the same set of traces, the odds ratio indicating the relative plausibility of the alternative routes can be found. An illustrative application to a BitTorrent piracy case is presented, and the results obtained suggest that the OCM is capable of providing a realistic estimate of the odds ratio for two competing hypotheses. It is also demonstrated that the OCM can be straightforwardly refined to encompass a variety of circumstances.

Estimating population size of the black-eared miner, with an assessment of landscape-scale habitat requirements

The decline of the Black-eared Miner Manorina melanotis has been caused primarily by habitat degradation and vegetation clearance. To better direct conservation actions for this species there was a need to assess habitat requirements on a regional-scale and to estimate the population size using quantitative methods. We used vegetation mapping and the current distribution of the Black-eared Miner to determine regional-scale habitat requirements. These findings were combined with the results of distance sampling to provide population estimates. The species is restricted to large tracts of intact mallee in the Murray Mallee of southeastern Australia that have not been burnt for at least 45 years. The density· of Black-eared Miners is highest in areas that are dominated by mallee- Triodia associations and have not been intensively grazed. The Bookmark Biosphere Reserve supports an estimated 501 (270-927, 95% CI) colonies, containing 3758 (2026-6954) phenotypically pure Black-eared Miners, 2255 (1 215-4170) hybrids and small numbers of Yellow-throated Miners Manorina flavigula. However, the effective population size is considerably smaller (390 Black-eared Miners '(21 0-726) and 234 hybrids (126-433)), due to a skewed adult sex ratio (1 female: 1.81 males) and complex social organization. A smaller population also persists in the Murray Sunset National Park containing 53 (32-85) Black-eared Miner/hybrid colonies. Both populations face a high risk of extinction from large-scale wildfire. The endangered status of the species under IUCN criteria remains warranted.

From parallel descriptions to parallel grammars: unravelling the complexity of Lutyen's country house folio

Based on an analysis of a corpus of forty of Sir Edwin Lutyens's country house designs (Rollo 1997) a procedure for developing Parallel Descriptions will be discussed. This procedure will attempt to facilitate an integrated approach to the analysis of complex architectural forms and will provide a framework for investigating the development of parallel grammars. This is an approach which acknowledges that design does not necessarily involve the importance of one aspect, but rather a number of coextensive issues with emphasis on the ordering and priority of these issues periodically shifting.

Habitat manipulation and rodent damage control: reducing rodent damage in Australian macadamia orchards

This paper examines the relationship between adjacent non-crop vegetation and rodent (Rattus rattus) damage in Australian macadamia (Macadamia integrifolia) orchard systems. Orchards adjacent to structurally diverse, non-crop vegetation dominated by woody weeds exhibited significantly higher damage when compared to orchards adjacent to managed grasslands. This relationship formed the basis for a rodent damage reduction strategy utilising habitat manipulation. Structurally diverse, non-crop habitats were modified to grasslands leading to a reduction in rodent damage of 65%. This strategy was cost-effective and has the potential to be long-term with minimal effort needed to maintain sites in a modified state. Habitat manipulation is a process whereby the resource load in a system is reduced and hence rodent densities cannot reach levels where they cause significant crop damage. This paper provides empirical evidence to support habitat manipulation as a practical, cost-effective control strategy for rodent pests.