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Predicting changes in the abundance of species over time is a central goal of conservation ecology. Typically, demographic data are used to parameterise models which describe population dynamics. Vital rates of plants vary across a species' distribution, yet most demographic estimates are spatially constrained. Banksia ornata (Proteaceae), a widespread serotinous obligate‐seeding shrub in southern Australia, has previously had a fire management model developed based on demographic data derived from a chronosequence in one part of the species' range. We asked: are demographic data collected from a limited geographic range robust for developing population dynamic models that are applied across the broader species' range? How much variation exists in the demography of species across their range and does this matter for estimating fire return intervals necessary for species persistence? We examine site‐to‐site variation in the pyrodemography of six populations of B. ornata encompassing its geographic range. We documented changes in population density, time to first reproduction and canopy seed bank accumulation in stands varying in age from 0.5 to 55 years. We model year of maximum seed production on demographic parameters such as population starting density and survival rate. Density, primary juvenile period, rates of mortality and seed bank accumulation varied across populations. Primary juvenile period varied across populations (from 6 to <20 years), while time to maximum seed production was estimated to take 34–39 years after fire. Hence, the fire intervals that correspond to minimising extinction risk (due to variation in primary juvenile periods) diverge moreso among populations than the fire intervals that produce (on average) the highest maximum seed production with respect to time since fire. Demographic data collected at different locations in a species' range are likely valuable for building realistic species response models to disturbance, providing underlying assumptions about key transitions, such as mortality rate, are made explicit. [ABSTRACT FROM AUTHOR]

Our understanding of the habitat needs of grassland fauna is often incomplete because of their cryptic behaviour. This presents a barrier to identifying important habitat attributes, whether these change at different spatial scales, and how this informs management decisions. Here, we use a critically endangered bird, the Plains‐wanderer (Pedionomus torquatus, Pedionomidae), as an exemplar of the challenge of managing grasslands for cryptic species. Until now, almost all ecological knowledge of Plains‐wanderers has come from the detection of nocturnally roosting individuals and habitat assessments at fine‐scales that indicate open swards are preferred habitat. We GPS‐tracked 13 adult Plains‐wanderers to better understand diurnal habitat utilization in native grasslands of south‐eastern Australia. Using these data, we assessed whether Plains‐wanderers select for different habitat attributes during the day and night, and whether this varied according to spatial scale. At the fine‐scale (< 1 ha), daytime foraging occurred in denser swards than those of nocturnal roosting sites. At the patch‐scale (1–50 ha), Plains‐wanderers selected for denser vegetation, with higher grass and lichen cover, whilst avoiding areas where structure was impacted by a high exotic plant cover. Plains‐wanderers did not select habitat based on grassland type at the landscape‐scale (>100 ha). We demonstrate that Plains‐wanderers require grasslands with both open and denser swards to support foraging and roosting. In doing so, we address the biases associated with habitat assessments based on roost‐only locations and extend known habitat associations critical to the successful management of the species. Our findings highlight that a precautionary approach to the classification of habitat requirements is warranted when uncertainty around habitat use of cryptic grassland fauna exists. [ABSTRACT FROM AUTHOR]

Fallen coarse woody debris (CWD) is critical to forest biodiversity and function. Few studies model factors that influence CWD availability, although such investigations are critically needed to inform sustainable forest management. We assess benchmark levels of CWD in unharvested native forests and those harvested for timber, across a range of forests in north‐east New South Wales, Australia. We found timber‐harvesting was the dominant driver of CWD, with almost double the count (pieces ha−1) and volume (m3 ha−1) of total CWD in selectively harvested than unharvested sites. This pattern was consistent across wet and dry forest types. Harvested sites had greater counts of hollow‐bearing logs, and greater volumes of small and medium‐sized CWD (15–50 cm diameter) than unharvested sites. There was no effect of harvesting on the volume of large CWD (>51 cm diameter). Total volumes of CWD (>15 cm diameter) varied from 114 to 166 m3 ha−1. We found few differences in CWD counts and volumes between forest types, with grassy woodlands and forests containing less CWD than other dry and shrubby forest types, reflecting lower potential input rates. The CWD levels recorded here are similar to those recorded in dry and wet sclerophyll forests elsewhere in Australia and are typical of global estimates for 'old growth' forests. Using general linear models we captured up to 57% of the variation in CWD across sites, and found that timber harvesting, topography and the numbers of standing hollow‐bearing and dead trees were significant predictors of CWD. Values for unharvested forest provide a benchmark that could be used to inform retention guidelines for CWD in managed forests in this region. Further assessment of the effect of repeat timber harvesting is needed to fully understand its impact on CWD dynamics, especially if forest residues resulting from timber harvesting are removed from native forests for bioenergy production. [ABSTRACT FROM AUTHOR]

In the face of massive human impacts upon the environment, a prevailing attitude among Australian ecologists seems to have become one of pessimism. The essay explores the consequences of this stance. Pessimism arises understandably from personal values favouring care for the natural world under conditions of rapid global change. Expression of such values is in no way illegitimate; pessimism is as justifiable a perspective as is optimism when interpreting ecology. Examples are mentioned of areas of Australian ecology where pessimism does not predominate, and where the ecological changes being wrought by the Anthropocene are accepted. But, the predominance of gloom can cause ecologists to flirt with exaggeration and with misanthropy, and perversely it can cause them to strive to prevent ecological change even though the discipline is rooted in the reality of flux. Most profoundly, it causes many citizens to switch off: gloom has limited capacity to motivate, whereas hope is the elixir of action. Because of predominant negativity, we risk losing the confidence of society. The solution is for the discipline to develop more diverse strands of interpretation, characterized by more equal doses of acceptance and hope. By balancing dejection, ecology may achieve the efficacy in debate and decision-making that it warrants in these challenging times. [ABSTRACT FROM AUTHOR]

Cane toads ( Bufo marinus) have invaded large areas of Australia, killing many native predators as they have done so. The metamorph stage of the life cycle – the first terrestrial phase, immediately after transformation from the tadpole – is critical for ecological impact (because these animals are small enough to be prey for many native predators) and for potential control of toad populations (because small body size renders metamorphs vulnerable to desiccation). To quantify the spatial and temporal distribution of metamorph toads, and the biotic and abiotic factors that might affect their distributions, we surveyed toad breeding sites in Australia's wet-dry tropics (Adelaide River floodplain, NT) in both the wet season and the dry season. Metamorphs were concentrated close to the water's edge during the dry season, especially at midday when desiccation rates were highest. During the wet season, metamorphs were widely dispersed through the landscape. Our surveys indicate that abiotic factors (risk of desiccation) are most favourable for metamorph toads close to the pond edge, but biotic factors (food supply, and risk of competition and cannibalism) are most favourable away from the water. Operative temperatures were spatially homogeneous and sublethal, and so are unlikely to influence metamorph distribution. Desiccation risk fluctuated on a diel cycle as well as seasonally. We predict that metamorph toads benefit from dispersing as soon as desiccation risk allows them to do so, and hence the distribution of metamorph toads will shift dynamically in response to weather-mediated changes in rates of evaporative water loss. [ABSTRACT FROM AUTHOR]

Abstract The distribution and area of temporary wetlands across the arid zone of Australia are highly variable. Any change in their distribution or extent due to climate change and/or extraction of water has the potential to adversely impact dependent biota. Satellite imagery was used to determine the spatial and temporal distribution of wetlands across arid Australia over an 11-year period. Synoptic climate data were examined to identify the weather systems that caused wetland filling events. Simple threshold models relating rainfall to wetland filling for seven large regions of Australia were developed to examine patterns of wetland filling over the last 100 years. These data were used to examine the climatic processes that drive wetland filling and the likely impacts of climate change on wetland distribution. The strongest climatic influence on wetland filling in the arid zone was tropical weather systems. Their influence extended into southern regions and their effects were often widespread. Variation in wetland area in all regions of the arid zone was high. The Lake Eyre Basin experienced more large flood events than other regions and had the most large, persistent wetlands that remain unregulated by humans. Hindcasting of past filling events indicated that there was a general pattern of frequent wetland filling across inland Australia in the 1910s, 1950s and 1970s, and less frequent wetland filling in the late 1920s, 1930s and 1960s. Furthermore, there appeared to be no period greater than 12 months over the previous 95 years when there was no predicted wetland filling in the arid zone. Wetland ecosystems dependent on a few infrequent heavy rainfalls are clearly vulnerable to any change in frequency or magnitude of these events. Climate change that results in a drying or reduced frequency of large flood events, exacerbated by extraction of water for agriculture, could be catastrophic for some biota, particularly waterbirds, which use a mosaic of wetland habitat at broad spatial scales. [ABSTRACT FROM AUTHOR]

Abstract There is a paucity of data on the movement patterns of feral cats in Australia. Such data can be used to refine control strategies and improve track-based methods of monitoring populations of feral cats. In this study the home ranges and movements of male feral cats were examined over 3.5 years in a semiarid woodland environment in central Australia. Two home range estimators were used in the examination: (i) minimum convex polygon (MCP); and (ii) fixed kernel. The most widely used method of estimating home range in feral cats is MCP, while the fixed kernel method can be used to identify core areas within a home range. On the basis of the MCP method, the long-term home ranges of feral cats in central Australia were much larger than those recorded elsewhere (mean, 2210.5 ha). Twenty-four hour home ranges were much smaller (mean, 249.7 ha) and feral cats periodically shifted their 24 h ranges within the bounds of their long-term home ranges. Core area analysis indicated marked heterogeneity of space use by male feral cats. Several instances where feral cats moved large distances (up to 34 km) were recorded. These long distance movements may have been caused by nutritional stress. Using data from the literature, it is shown that prey availability is a primary determinant of long-term home range size in feral cats. The relevance of the results to the design of management strategies for feral cats in central Australia is also discussed. [ABSTRACT FROM AUTHOR]