Now showing 1 - 10 of 37
  • Publication
    Social, conservation and economic implications of rabies in Australia
    (Royal Zoological Society of New South Wales, 2017)
    Sparkes, Jessica
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    ; ;
    Biophilia, our inherent love of living things, is a major driver of the modern conservation ethic worldwide. Australians are particularly fond of wildlife and consequently, our fauna are key to our national image. As a nation, we are known for our relatively carefree attitude towards some of the world's most dangerous animals, including venomous snakes and spiders, as well as sharks. This has arisen largely because we are familiar with these species, understand the actual level of risk they pose and have some idea of how to safely interact with them. Unfortunately, the relationship between Australians and our wildlife could change significantly. Canine rabies, an infamous, fatal, viral zoonosis, is now less than 300 kilometers from the Australian mainland. We must face the possibility of a 'when', rather than 'if' scenario and begin to plan for rabies management on a continent where virtually the entire population is naïve. Human and animal health would be affected. People, domestic animals and wildlife may die. Perhaps worse, in terms of scale, is the likely change in the Australian way of life, including the way we perceive, value and interact with wildlife, pets and livestock. Of course, rabies is endemic in many other countries and people continue to actively engage in conservation programs, but these people have had a long time to come to terms with the risk in their midst and many undergo prophylactic vaccination to enable them to work with wildlife. Here, we discuss Australia's impending future with particular regard to how canine rabies could change our lives, the impacts it could have on wildlife conservation and the steps we must take to be prepared.
  • Publication
    Invasive species and their impacts on agri-ecosystems: issues and solutions for restoring ecosystem processes
    (CSIRO Publishing, 2017-11-28) ; ; ;
    Tracey, John P

    Humans are the most invasive of vertebrates and they have taken many plants and animals with them to colonise new environments. This has been particularly so in Australasia, where Laurasian and domesticated taxa have collided with ancient Gondwanan ecosystems isolated since the Eocene Epoch. Many plants and animals that humans introduced benefited from their pre-adaptation to their new environments and some became invasive, damaging the biodiversity and agricultural value of the invaded ecosystems. The invasion of non-native organisms is accelerating with human population growth and globalisation. Expansion of trade has seen increases in purposeful and accidental introductions, and their negative impacts are regarded as second only to activities associated with human population growth. Here, the theoretical processes, economic and environmental costs of invasive alien species (i.e. weeds and vertebrate pests) are outlined. However, defining the problem is only one side of the coin. We review some theoretical underpinnings of invasive species science and management, and discuss hypotheses to explain successful biological invasions. We consider desired restoration states and outline a practical working framework for managing invasive plants and animals to restore, regenerate and revegetate invaded Australasian ecosystems.

  • Publication
    Canine rabies in Australia: Modelling spread through the landscape
    (Australasian Society for Infectious Diseases, 2014)
    Sparkes, Jessica
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    ; ; ;
    Introduction: Canine rabies, a fatal viral zoonosis, is now less than 300 kilometres from Indonesian archipelago. To respond to this imminent threat, we need to model how rabies will spread through Australian ecosystems, to develop effective rabies management plans. This will improve our chances of minimising reaction times and containing outbreaks. Aims: To quantify contact rates, abundance, population turnover and dog bite frequency, in order to inform models of canine rabies spread. This is essential for identifying critical control points.
  • Publication
    Canine Rabies will alter how we manage wild dogs in Australia
    (Biosecurity Queensland, 2014)
    Sparkes, Jessica
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    Ballard, Guy
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    ;
    Canine rabies, a fatal viral zoonosis, is now less than 300 kilometres from Australia's mainland and continues to spread eastwards through the Indonesian archipelago. Rabies incursion into Australia will alter our society's perceptions of wild dog management, particularly in peri-urban areas where contact can occur between wild dogs, pets and people. Canine rabies will not only have major implications for Australian pest animal management, but will also impact upon how Australians interact with domestic animals and native wildlife. Fear of infection may increase pressure to kill or tightly control dogs and will likely require land managers to adapt how they manage people and wild dogs in densely populated areas. To respond to this imminent threat, we need to model how rabies will spread through Australian ecosystems so that we can develop effective rabies management plans. This will minimise reaction times and improve our chances of containing outbreaks. Here, we present preliminary data collected to inform rabies management plans. Firstly, we use data from GPS-telemetry collars fitted to domestic and wild dogs, as well as data from camera traps, to provide insight into dog-dog and human-dog contact rates. Secondly, we present and discuss the results from self-administered surveys focussed on dog ownership and dog bites, hunting dog movements and interactions between hunting dogs and wild dogs, all of which are vital to understand, detect and manage canine rabies when it reaches Australia.
  • Publication
    Effects of Sex and Reproductive State on Interactions between Free-Roaming Domestic Dogs
    (Public Library of Science, 2014)
    Sparkes, Jessica
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    ; ; ;
    Free-roaming dogs ('Canis familiaris') are common worldwide, often maintaining diseases of domestic pets and wildlife. Management of these dogs is difficult and often involves capture, treatment, neutering and release. Information on the effects of sex and reproductive state on intraspecific contacts and disease transmission is currently lacking, but is vital to improving strategic management of their populations. We assessed the effects of sex and reproductive state on short-term activity patterns and contact rates of free-roaming dogs living in an Australian Indigenous community. Population, social group sizes and rates of contact were estimated from structured observations along walked transects. Simultaneously, GPS telemetry collars were used to track dogs' movements and to quantify the frequency of contacts between individual animals. We estimated that the community's dog population was 326±52, with only 9.8±2.5% confined to a house yard. Short-term activity ranges of dogs varied from 9.2 to 133.7 ha, with males ranging over significantly larger areas than females. Contacts between two or more dogs occurred frequently, with entire females and neutered males accumulating significantly more contacts than spayed females or entire males. This indicates that sex and reproductive status are potentially important to epidemiology, but the effect of these differential contact rates on disease transmission requires further investigation. The observed combination of unrestrained dogs and high contact rates suggest that contagious disease would likely spread rapidly through the population. Pro-active management of dog populations and targeted education programs could help reduce the risks associated with disease spread.
  • Publication
    Human-resource subsidies alter the dietary preferences of a mammalian top predator
    (Springer, 2014)
    Newsome, Thomas M
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    ; ;
    van de Ven, Remy
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    Story, Georgeanna
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    Dickman, Chris
    Resource subsidies to opportunistic predators may alter natural predator-prey relationships and, in turn, have implications for how these predators affect co-occurring prey. To explore this idea, we compared the prey available to and eaten by a top canid predator, the Australian dingo ('Canis lupus dingo'), in areas with and without human-provided food. Overall, small mammals formed the majority of dingo prey, followed by reptiles and then invertebrates. Where human-provided food resources were available, dingoes ate them; 17% of their diet comprised kitchen waste from a refuse facility. There was evidence of dietary preference for small mammals in areas where human-provided food was available. In more distant areas, by contrast, reptiles were the primary prey. The level of seasonal switching between small mammals and reptiles was also more pronounced in areas away from human-provided food. This reaffirmed concepts of prey switching but within a short, seasonal time frame. It also confirmed that the diet of dingoes is altered where human-provided food is available. We suggest that the availability of anthropogenic food to this species and other apex predators therefore has the potential to alter trophic cascades.
  • Publication
    Impacts and management of invasive burrowing herbivores in grasslands
    (NSW Government, Department of Primary Industry, 2013) ;
    Limin, Hua
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    Whisson, Desley
    Maintenance of the productivity of the world's grasslands is critical for livestock production, bio-diversity conservation and ecosystem services. Using case studies from Australasia, North America and China, we identify general principles of managing invasive native and introduced herbivores. Management aims to achieve optimised livestock production while conserving biodiversity and ecosystem services, which are often intangible. We identify similarities and differences in the ecologies and impacts of European wild rabbits, Californian ground squirrel and plateau zokors, discuss management tools and strategies, and the eco-logical, social and cultural factors affecting management. The ecosystem engineering characteristics of these species that make them important for ecosystem function in grasslands are perversely the selfsame ones that bring them into conflict with livestock producers. All three species create habitat patches through their bur-rowing and foraging behaviours, but changes in vegetation floristics and structure, increased soil exposure and decreased litter negatively affect grassland and livestock production when the animals are superabundant. Management is therefore complex and we recommend an adaptive approach that is founded on the scientific knowledge of the local agri-ecosystem, economic principles and social inclusion to increase knowledge and iteratively improve management.
  • Publication
    Seven considerations about dingoes as biodiversity engineers: the socioecological niches of dogs in Australia
    (CSIRO Publishing, 2012) ;
    Allen, Benjamin
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    Ballard, Guy-Anthony
    Australian dingoes have recently been suggested as a tool to aid biodiversity conservation through the reversal or prevention of trophic cascades and mesopredator release. However, at least seven ecological and sociological considerations must be addressed before dog populations are positively managed. 1. Domestication and feralisation of dingoes have resulted in behavioural changes that continue to expose a broad range of native and introduced fauna to predation. 2. Dingoes and other dogs are classic mesopredators, while humans are the apex predator and primary ecosystem engineers in Australia. 3. Anthropogenic landscape changes could prevent modern dingoes from fulfilling their pre-European roles. 4. Dingoes are known to exploit many of the same species they are often presumed to 'protect', predisposing them to present direct risks to many threatened species. 5. The assertion that contemporary dog control facilitates the release of mesopredators disregards the realities of effective dog control, which simultaneously reduces fox and dog abundance and is unlikely to enable increases in fox abundance. 6. The processes affecting threatened fauna are likely a combination of both top-down and bottom-up effects, which will not be solved or reversed by concentrating efforts on managing only predator effects. 7. Most importantly, human social and economic niches are highly variable across the ecosystems where dingoes are present or proposed. Human perceptions will ultimately determine acceptance of positive dingo management. Outside of an adaptive management framework, positively managing dingoes while ignoring these seven considerations is unlikely to succeed in conserving native faunal biodiversity but is likely to have negative effects on ecological, social and economic values.
  • Publication
    Does lethal control of top-predators release mesopredators? A re-evaluation of three Australian case studies
    (Wiley-Blackwell Publishing Asia, 2014)
    Allen, Benjamin
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    Lundie-Jenkins, Geoff
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    Burrows, Neil D
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    Engeman, Richard M
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    Leung, Luke K P
    Top-predators can sometimes be important for structuring fauna assemblages in terrestrial ecosystems. Through a complex trophic cascade, the lethal control of top-predators has been predicted to elicit positive population responses from mesopredators that may in turn increase predation pressure on prey species of concern. In support of this hypothesis, many relevant research papers, opinion pieces and literature reviews identify three particular case studies as supporting evidence for top-predator controlinduced release of mesopredators in Australia. However, many fundamental details essential for supporting this hypothesis are missing from these case studies, which were each designed to investigate alternative aims. Here, we re-evaluate the strength of evidence for top-predator control-induced mesopredator release from these three studies after comprehensive analyses of associated unpublished correlative and experimental data. Circumstantial evidence alluded to mesopredator releases of either the European Red Fox ('Vulpes vulpes') or feral Cat ('Felis catus') coinciding with Dingo ('Canis lupus dingo') control in each case. Importantly, however, substantial limitations in predator population sampling techniques and/or experimental designs preclude strong assertions about the effect of lethal control on mesopredator populations from these studies. In all cases, multiple confounding factors and plausible alternative explanations for observed changes in predator populations exist. In accord with several critical reviews and a growing body of demonstrated experimental evidence on the subject, we conclude that there is an absence of reliable evidence for top-predator control-induced mesopredator release from these three case studies. Well-designed and executed studies are critical for investigating potential top-predator control-induced mesopredator release.
  • Publication
    The trophic cascades concept may constrain Australian dingo reintroduction experiments: A response to Newsome et al. (2017)
    We are in some agreement with Newsome et al. (2017): the differences between the ecosystems of Yellowstone and Sturt National Parks should not preclude examinations of the influences, whether costs (see Allen and Fleming, 2012) or benefits of the dingo (Canis familiaris), on contemporary Australian ecosystems. It is important to note that at no point did Morgan et al. (in press) suggest that experimentation should not occur. Rather, we acknowledged that proposals to reintroduce dingoes to south east Australia (Letnic and Koch, 2010; Visser et al., 2009) and Sturt National Park (Newsome et al., 2015a) were developed in response to a recognised need for manipulative experiments to understand the true ecological role of the dingo (Allen et al., 2013b; Fleming et al., 2012; Hayward and Marlow, 2014; Letnic and Koch, 2010). Rather than advocating against dingo reintroduction experiments, Morgan et al. (in press) outlined a case for not relying on the conceptual framework of the trophic cascade model to frame predator reintroduction experiments in Australia. This is because the design of experiments based on a theory of trophic cascades, that originated in environments governed by a stable climate, are likely to be constrained by that theory rather than enhanced. We believe a more objective and sound approach would be to consider multiple working hypotheses (Chamberlin, 1965).