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Patterns in the modern decline of western Australia's vertebrate fauna: Causes and conservation implications

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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 5500 g.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.
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... When patch burning ceased, or was degraded, biological productivity was lost after about five years. Burbidge and McKenzie (1989) identified biological productivity loss as the primary cause of Critical Weight Range mammal extinctions in the arid and semi-arid zones. Menkhorst (2009) found loss of TO-LM plausible but rejected it because: a) 'it struggles to account for the rapidity of the mammal declines' as it would take some years to transform the fine-grain mosaic to coarse grain (awaiting senescence and bushfires); and b) there was scant evidence that Aboriginal people applied a patch-mosaic fire regime at a broad scale in this part of Australia. ...
... Furthermore, our subtraction argument also fits the progressive loss of mammal species across the continent over the following century (e.g. Burbidge & McKenzie 1989;Latz & Griffin 1978). If, as we contend, the cessation of TO-LM is the initial causal factor driving mammal extinctions, then a suite of expanded actions (hitherto ignored) for redress of the acknowledged continental declines of ecosystems becomes available. ...
... In analysing the twentieth-century attrition and extinction of species in WA (and across Australia) Burbidge and McKenzie (1989) attributed the loss of native fauna to the loss of available productivity, most pronounced in Critical Weight Range mammals that had relatively high metabolic requirements (c.f. reptiles) and lesser mobility (c.f. ...
Article
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... Between the 1980s and the early 2000s, a body of evidence was generated on the impacts of foxes on native species in Australia (e.g. Burbidge and McKenzie 1989;Kinnear et al. 2002). The evidence indicated that foxes are omnivorous hunters that prey on small native mammals, birds, reptiles, amphibians and insects as well as eating fruits (Triggs et al. 1984). ...
... The evidence indicated that foxes are omnivorous hunters that prey on small native mammals, birds, reptiles, amphibians and insects as well as eating fruits (Triggs et al. 1984). Fox predation has been implicated as the main factor in the complete or regional extinction of a range of critical weight range (35-5,500 g) native mammals (Burbidge and McKenzie 1989;Short and Smith 1994), as well as small reptiles (Olsson et al. 2005;Stobo-Wilson et al. 2021) and ground-nesting birds (Dickman 1996). ...
... Anon, 2018), however, little research has been undertaken to confirm these hypothesized threats to the species or the level of impact. Parma wallabies fall within the critical weight range body mass of Australian fauna that has been decimated by introduced predators (Burbidge and McKenzie, 1989) and hence are clearly threatened by eutherian predators. While introduced red foxes are a threat (Catling and Burt, 1994), parma wallabies are also killed by dingoes (Robertshaw and Harden, 1986;Glen et al., 2006) and the young are likely killed by feral cats. ...
... The critical weight range refers to the body mass of mammals that have declined since European colonization of Australia due to the effects of introduced species(Burbidge and McKenzie, 1989). It originally ranged from 35 g to 5.5 kg, but may be larger than this.Imperiled: The Encyclopedia of Conservation https://doi.org/10.1016/B978-0-12-821139-7.00150-1 ...
... nov. falls within, or close to a critical weight range of mammals prone to feral cat (Felis catus) and red fox (Vulpes vulpes) predation (35-5500 g) (Burbidge and McKenzie 1989;Woolley et al. 2019). Given the paucity of knowledge, it is unknown what the impact of cat predation is on the subspecies. ...
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... The eastern quoll ('murunguny' in the local Indigenous Ngunnawal language) is a small-to-medium (0.7e2 kg), critical weight range (Australian mammals between 35 and 5500 g which suffer the greatest attrition from predation by introduced predators, Burbidge & McKenzie, 1989), carnivorous marsupial (family Dasyuridae, Stannard & Old, 2013). As generalist predators, they hunt mammals, birds, reptiles, crustaceans and invertebrates, and will also scavenge on carcasses (Blackhall, 1980;Godsell, 1983). ...
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Article
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... desertification, erosion) and many native wildlife species (e.g. declines and extinctions) in the 1800s and 1900s (Burbidge and McKenzie, 1989;Idriess, 2001;McKenzie et al., 2007;Woinarski et al., 2015). Many threatened species presently exist within the region where these cluster fences are being erected, including small mammals, ground-dwelling birds, and reptiles (Smith et al., 2020b). ...
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