Ecological attributes of the threatened fauna of New South Wales (original) (raw)
Related papers
Mammals of particular conservation concern in the Western Division of New South Wales
Biological Conservation, 1993
trative region of 325 000 km: on the eastern fringe of the Australian arid zone. Since European settlement in 1788, 71 species of native mammals have been recorded in the Division, seven more have been documented only as subfossils, and a further 15 species occur within 100 km of the Divisional boundary. At least 27 of the original species have become regionally extinct, and a further 11 have declined in distribution. As in other regions of Australia, species losses have been greatest for rodents and marsupials in a critical weight range of 35-5500 g, and least for bats. However, percentage losses among the terrestrial fauna are high relative to other regions, and probably reflect both the early settlement of New South Wales and the marginal distribution in the Division of 49% of the original fauna. Feral cats are implicated in the regional extinction of up to ten species of native mammals prior to 1857. Subsequent extinctions and range reductions are attributed to combinations of causes, including predation from cats Felis catus and red foxes Vulpes vulpes, competition and habitat degradation from rabbits Oryctolagus cuniculus, stock and other introduced herbivores, clearing of trees, changes in fire regimes and human persecution. We identified 28 species of particular conservation contern in the Division based on low abundance, distribution or survival prognosis. Nine species are of national significance, fi~ur of state, and 15 of regional, significance. The major current threats to these species are from grazing by stock, interference from feral mammals and clearing. Further land reservation is an important conservation mea-Biological Conservation 0006-3207/93/$06.00 © 1993 Elsevier Science Publishers Ltd, England. Printed in Great Britain sure, but must be complemented by more effective management of non-reserved land and by broad-scale management of feral species and other threatening processes if the current species diversity is to be maintained Long-term fauna surveys should be initiated throughout the Western Division to provide feedback on the effectiveness of management measures, and species reintroductions should be considered in situations where threats have been removed
The threats endangering Australia's at-risk fauna
Reducing the rate of species extinctions is one of the great challenges of our time. Understanding patterns in the distribution and frequency of both threatened species and the threatening processes affecting them improves our ability to mitigate threats and prioritize management actions. In this quantitative synthesis of processes threatening Australian at-risk fauna, we find that species are impacted by a median of six threats (range 1-19), though there is considerable variation in numbers of threats among major taxonomic groups. Invasive species, habitat loss, biological resource use, natural systems modification and climate change are the processes most commonly affecting Australian threatened species. We identified an uneven distribution of research knowledge among species, with half of the total number of species-specific peer-reviewed scientific publications associated with only 11 threatened species (2.7%). Furthermore, the number of threats associated with each species was correlated with the research effort for that species, and research effort was correlated with body mass. Hence, there appears to be a research bias towards larger-bodied species, and certain charismatic species, that could result in inferences biased towards these favored species. However, after accounting for these effects we found that for birds, amphibians, reptiles and marine mammals body mass is positively correlated with the number of threats associated with each species. Many threats also co-occur, indicating that threat syndromes may be common.
Conserving the forest mammals of New South Wales
Conservation of Australia's Forest Fauna, 2004
Invertebrates dominate both terrestrial and aquatic environments in terms of their diversity, yet few have been listed as threatened. Does this really mean that few species are threatened, or is it more likely that we just do not know enough about invertebrate populations? Realistically, given the slow acquisition of knowledge of invertebrates in Australia, it is argued that listing of invertebrates is suitable only for "iconic" species in order to raise community awareness. A more effective avenue is the conservation of habitats or communities for invertebrates as well as the implementation of legislation to identify and tackle key threatening processes. Until both the public and scientific community become aware of the importance of invertebrates in ecosystem functioning, there will be little pressure on conservation agencies to conserve invertebrates.
Biological Conservation, 1989
The conservation status of terrestrial vertebrates occurring on the mainland of Western Australia was assessed. Extinctions and declines are virtually confined to non-flying mammals with mean adult body weights between 35 g and 4200 g. Variation in patterns of attrition within this critical weight range (CWR) can be explained almost entirely by a combination of regional patterns in rainfall and, to a lesser extent, species' habitat and dietary preferences. Similar patterns of mammal attrition were recognisable throughout the continent, except that the CWR was 35 to 5500g. Environmental changes since European settlement have emulated an increase in aridity by reducing the environmental productivity available to vertebrates. These include the diversion of environmental resources to humans and introduced species, and a reduction in vegetative cover by exotic herbivores and changed fire regimes. Our analyses support the view that the reduction in available productivity has caused CWR mammals to suffer the greatest attrition because of their limited mobility, but relatively high daily metabolic requirements. The direct elimination of confined populations of mammals by exotic predators has exacerbated this attrition. We derive priorities for the conservation of Australian mammals.
Threatened species legislation, 2004
In this chapter we apply an ecological approach to considering the vertebrate species listed on the current schedules of the NSW Threatened Species Conservation Act 1995. We do so in light of our knowledge of the threats that have impacted on the vertebrate fauna of NSW, but mainly as a reflection on our role as the Scientific Committee (1992-95) in formulating the schedules of threatened fauna under the Endangered Fauna (Interim Protection) Act 1991. We reflect on the limitations of this process, including constraints on time, a lack of adequate knowledge for most species and differences in expert opinion. The final 1992 list included 236 threatened vertebrate species, or 26% of the fauna of NSW. Threatened species have since been elevated by instruments of government and land-use decisions to such a degree that other species are apparently no longer of interest. Thus 74% of our vertebrate fauna has become neglected. Many species are missing out on research effort, and other conceptual approaches, such as threatening processes, are not given priority. In our opinion, the apparent immutability of the scheduled species is illogical given the uncertainty of the listing process, and we see a pressing need for a dynamic database of species status so that the schedules reflect new knowledge and changes in the status of species as they occur. Threatened species deserve special attention, but their relative importance in the wider conservation agenda needs re-examination if we are to fulfil the broader aims of conserving biodiversity.
A review of the conservation status of Australian mammals
Introduction: This paper provides a summary of results from a recent comprehensive review of the conservation status of all Australian land and marine mammal species and subspecies. Since the landmark date of European settlement of Australia (1788), at least 28 of the ca. 272 Australian endemic land mammal species have been rendered extinct. Results and Discussion: Extinctions have occurred at a more or less consistent rate of one to two species per decade since the 1840s, with that rate continuing unabated. A further 55 species from that original fauna are now threatened, and an additional 42 are Near Threatened. Although many factors have contributed to these declines and extinctions, and the array of threats varies amongst individual species, the threat that has had (and is continuing to have) most detrimental impact upon terrestrial mammal species is predation by the introduced cat Felis catus and European red fox Vulpes vulpes. There has been some successful broad-scale management of the fox, but the threat posed by feral cats remains largely unabated. For the 55 species occurring in Australian marine waters, the information base is mostly too meagre to assess conservation status other than as Data Deficient. For the Australian mammal fauna generally, the current conservation management effort is insufficient, with ongoing trends for decline in many species-for example, of 49 species whose conservation status changed over the period 1992-2012, 38 had deteriorating conservation status whereas only 11 had improving status.
Recent studies at some sites in northern Australia have reported severe and rapid decline of some native mammal species, notwithstanding an environmental context (small human population size, limited habitat loss, substantial reservation extent) that should provide relative conservation security. All of the more speciose taxonomic groups of mammals in northern Australia have some species for which the conservation status has been assessed as threatened, with 53% of dasyurid, 46% of macropod and potoroid, 33% of bandicoot and bilby, 33% of possum, 31% of rodent, and 24% of bat species being assessed as extinct, threatened or Near Threatened. This paper reviews disparate recent and ongoing studies that provide information on population trends across a broader geographic scope than the previously reported sites, and provides some information on the conservation status and trends for mammal groups (bats, larger macropods) not well sampled in previous monitoring studies. It describes some diverse approaches of studies seeking to document conservation status and trends, and of the factors that may be contributing to observed patterns of decline. The studies reported provide some compelling evidence that predation by feral cats is implicated in the observed decline, with those impacts likely to be exacerbated by prevailing fire regimes (frequent, extensive and intense fire), by reduction in ground vegetation cover due to livestock and, in some areas, by ‘control’ of dingoes. However the impacts of dingoes may be complex, and are not yet well resolved in this area. The relative impacts of these individual factors vary spatially (with most severe impacts in lower rainfall and less topographically rugged areas) and between different mammal species, with some species responding idiosyncratically: the most notable example is the rapid decline of the northern quoll Dasyurus hallucatus due to poisoning by the introduced cane toad Rhinella marina, which continues to spread extensively across northern Australia. The impact of disease, if any, remains unresolved. Recovery of the native mammal fauna may be impossible in some areas. However, there are now examples of rapid recovery following threat management. Priority conservation actions include: enhanced biosecurity for important islands, establishment of a network of substantial predator exclosures, intensive fire management (aimed at increasing the extent of longer-unburnt habitat and in delivering fine scale patch burning), reduction in feral stock in conservation reserves, and acquisition for conservation purposes of some pastoral lands in areas that are significant for mammal conservation.
National context for the conservation fate of Victoria’s mammal fauna
Victorian naturalist, 2016
This paper provides a broad international and national context for the symposium’s focus on the conservation of the Victorian mammal fauna. As with Australia generally, the Victorian mammal fauna has suffered rates of extinction that are unusually high by global standards. The main factors that have caused loss of Australia’s land mammals are predation (by the introduced feral Cat and Red Fox) and changed fire regimes, although other factors are also implicated in declines for some species. There are reasonable grounds for hope that the ongoing decline in Victoria’s mammal fauna can be stemmed and reversed, especially because it is plausible to return, with intensive management, many of the 14 mammal species that have been extirpated from Victoria but have persisted elsewhere. (The Victorian Naturalist 133(3), 2016, 74–78)
Mammals of the Coastal Forests near Bega New South Wales: II. Annotated Checklist
Australian Zoologist, 1987
A survey of the mammals of the coastal State Forests, adjacent farmlands and coastal national park near Bega, on the south coast of New South Wales, was undertaken between 1979 and 1984. A total of 39 native and 10 exotic species was found in the area surveyed. That 17 (44%) of the native species were bats demonstrates the importance of considering this order of mammals in both future surveys and forest management. The presence of species varied according to the land-use category of the area surveyed. State Forest was richest and contained 37 of the 39 native species found. Coastal national park supported 17 native species, while only 7 were found on farmland. Of the 39 species, 14 were considered rare in the survey area, 11 were uncommon and 14 common. Of the twelve methods of detection used, the most productive was predator scat analysis, which yielded 24 native species and 9 exotic species. The survey was conducted using a wide variety of detection methods in logged and unlogged, burnt and unburnt forest and through drought years. Observations were made about the impact of logging, fire and drought on native mammals and proposals made for their conservation and management.
A biological survey of the Pilbara biogeographic region was undertaken between 2002 and 2007 to provide a regional perspective on biodiversity patterns as a contribution to nature conservation planning. During this survey, 304 sites were sampled for small ground-dwelling mammals, birds, reptiles, spiders, ants, beetles and scorpions. A further 98 sites were sampled for wetland invertebrates, aquatic macrophytes and fringing riparian vegetation. Data for these two groups of sites were aggregated separately (i.e. terrestrial fauna and wetland biodiversity) and models of turnover in species composition within each data set were developed using generalised dissimilarity modelling (GDM). A wide range of environmental variables was assessed as predictors of compositional turnover -biotic (vegetation cover indices), climate, landform, hydrologic, regolith (soil and geology) and geographic distance. Generally, predictors associated with regolith were the most strongly supported in both the terrestrial fauna and wetland biodiversity models, followed by combined landform/ hydrologic variables, then climate/biotic variables. Geographic distance between sites was retained in the terrestrial fauna model only. The fi nal GDM models explained 46.1% and 58.5% of the deviance in the compositional turnover of terrestrial fauna and wetland biodiversity, respectively. Spatial representation of the coverage of survey sites showed that a large proportion of the core study area was well represented for both terrestrial fauna and wetland biodiversity. However, gaps in the proportional representation of both groups within the 2011 conservation reserve system were evident, particularly in the coastal region of the Pilbara (Roebourne subregion) and the Fortescue River valley (Fortescue subregion). With the addition of proposed reserves (in 2015) within these two subregions, the representation of terrestrial fauna and wetland biodiversity was substantially improved.