Abstract Introduced predators pose threats to biodiversity and are implicated in the extinction of many native species. In Australia, considerable effort is spent controlling populations of introduced predators, including the dingo Canis dingo and the red fox Vulpes vulpes, to reduce their effects on native species and livestock. Studies describe different outcomes of controlling dingo and fox populations on native species, making biodiversity management decisions difficult for conservation managers. We conduct a meta‐analysis to compare the impacts that control programmes targeted towards dingoes and foxes in Australia have on introduced predators and on other mammal species, including native species and prey species. Our results provide evidence that lethal control of dingoes and foxes has different outcomes for different mammalian species. Dingo removal had a negative effect on the abundance of native mammals weighing less than the critical weight range (CWR) of 30–5500 g, and a positive effect on the abundance of mammals above the CWR. Fox abundance increased in response to dingo control, but confidence intervals were large. Fox removal had strong positive effects on ground‐dwelling and arboreal mammals. Lethal control of dingoes did not have a significant effect on cats, but where dingoes were removed there was a tendency for foxes to increase, and where foxes were removed there was a tendency for cats to increase. Our results highlight unintended and perverse outcomes of lethal predator control on Australian mammals. Lethal control of dingoes significantly increases abundances of above CWR mammals and significantly decreases abundances of under CWR mammals. Lethal control of foxes significantly increases the abundances of CWR mammals. These findings show how removing dingoes and foxes alters mammal assemblages and provide comprehensive and objective information for conservation managers. We recommend that land management agencies take the results of this study into consideration when planning lethal control programmes targeting dingoes and foxes because, depending on the target canid, these programmes result in different outcomes for other mammal species. Removal programmes targeting dingoes and/or foxes can result in increased abundances of introduced predators and, ultimately, have far‐reaching effects on many mammal species.

Accelerometers are a valuable tool for studying animal behaviour and physiology where direct observation is unfeasible. However, giving biological meaning to multivariate acceleration data is challenging. Here, we describe a method that reliably classifies a large number of behaviours using tri-axial accelerometer data collected at the low sampling frequency of 1 Hz, using the dingo (Canis dingo) as an example. We used out-of-sample validation to compare the predictive performance of four commonly used classification models (random forest, k-nearest neighbour, support vector machine, and naïve Bayes). We tested the importance of predictor variable selection and moving window size for the classification of each behaviour and overall model performance. Random forests produced the highest out-of-sample classification accuracy, with our best-performing model predicting 14 behaviours with a mean accuracy of 87%. We also investigated the relationship between overall dynamic body acceleration (ODBA) and the activity level of each behaviour, given the increasing use of ODBA in ecophysiology as a proxy for energy expenditure. ODBA values for our four 'high activity' behaviours were significantly greater than all other behaviours, with an overall positive trend between ODBA and intensity of movement. We show that a random forest model of relatively low complexity can mitigate some major challenges associated with establishing meaningful ecological conclusions from acceleration data. Our approach has broad applicability to free-ranging terrestrial quadrupeds of comparable size. Our use of a low sampling frequency shows potential for deploying accelerometers over extended time periods, enabling the capture of invaluable behavioural and physiological data across different ontogenies.

Eating Dingoes

K’gari (Fraser Island) offers a rare opportunity for people to observe and encounter wild dingoes. Occasionally, however, such encounters can entail dingoes acting in a threatening or aggressive manner towards people, resulting in human injury and, in one tragic case, death. A suite of approaches aimed at minimising the risk to human safety posed by dingoes have been implemented on the island, including fencing, island-wide warning signage, and regulations against feeding. Despite such measures, negative encounters continue, and in cases where dingoes are deemed to pose an unacceptable risk, they are usually destroyed. In searching for non-lethal management alternatives, attempts have been made to modify undesirable dingo behaviour through aversive conditioning, but results to date have either been mixed or largely disappointing. Here we review a wide array of research that has utilised aversive stimuli in an effort to modify and manage the behaviour of wild animals, with a particular focus on related predators such as coyotes and wolves. We identified eight major categories of experimental research: conditioned taste aversion/avoidance (CTA), electric fencing, fladry, chemical repellents, fear-evoking stimuli, physical repellents, aversive collars/devices and hard release procedures. We then outline each of these categories in more detail, complete with pertinent examples of successes and failures as well as advantages and disadvantages. We conclude that some approaches offer promise within three main areas of incident mitigation experimentation: dingo exclusion (e.g. electric fencing), personal protection (mild chemical irritant sprays, sturdy umbrellas) and remedial aversive conditioning (e.g. shock collars). Other approaches, such as CTA and sublethal projectiles are not recommended. Like any approach, aversive conditioning is not a panacea, but it does offer promise in filling gaps in current management and as an alternative to lethal control.

Uncovering the origins of dog–human eye contact: dingoes establish eye contact more than wolves, but less than dogs

The taxonomic identity and status of the Australian Dingo has been unsettled and controversial since its initial description in 1792. Since that time it has been referred to by various names including Canis dingo, Canis lupus dingo, Canis familiaris and Canis familiaris dingo. Of these names C. l. dingo and C. f. dingo have been most often used, but it has recently been proposed that the Australian Dingo should be once again recognized as a full species—Canis dingo. There is an urgent need to address the instability of the names referring to the Dingo because of the consequences for management and policy. Therefore, the objective of this study was to assess the morphological, genetic, ecological and biological data to determine the taxonomic relationships of the Dingo with the aim of confirming the correct scientific name. The recent proposal for Canis dingo as the most appropriate name is not sustainable under zoological nomenclature protocols nor based on the genetic and morphological evidence. Instead we proffer the name C. familiaris for all free-ranging dogs, regardless of breed and location throughout the world, including the Australian Dingo. The suggested nomenclature also provides a framework for managing free-ranging dogs including Dingoes, under Australian legislation and policy. The broad principles of nomenclature we discuss here apply to all free-roaming dogs that coexist with their hybrids, including the New Guinea Singing Dog.

Predators often display dietary shifts in response to fluctuating prey in cyclic systems, but little is known about predator diets in systems that experience non-cyclic prey irruptions. We tracked dietary shifts by feral cats (Felis catus), red foxes (Vulpes vulpes) and dingoes (Canis dingo) through a non-cyclic irruption of small mammalian prey in the Simpson Desert, central Australia. We predicted that all three predators would alter their diets to varying degrees as small mammals declined post irruption, and to test our predictions we live-trapped small mammals through the irruption event and collected scats to track predator diets. Red foxes and dingoes included a broader variety of prey in their diets as small mammals declined. Feral cats did not exhibit a similar dietary shift, but did show variable use and selectivity of small mammal species through the irruption cycle. Results were largely consistent with prior studies that highlighted the opportunistic feeding habits of the red fox and dingo. They also, however, showed that feral cats may exhibit less dietary flexibility in response to small mammal irruptions, emphasizing the importance of tracking predator diets before, during and after irruption events.

Occasionally, interactions between dingoes (Canis dingo) and people on Fraser Island result in serious injury, and, in one case, death. The risk to human safety from such interactions may be mitigated if people could carry a suitably defensive repellent, similar in principle to bear (Ursus spp.) repellent spray advocated in North America. In the first step towards searching for suitable stimuli that might be used as repellents with dingoes, we observed the responses of nine dingoes to three stimuli during interactions with a researcher on Fraser Island. Two treatment stimuli were assumed to be potentially aversive (an air horn blast and a water jet from a motorised water pistol), and one was considered unlikely to be aversive and therefore suitable as a control (a whistle being blown). Responses to the stimuli varied. All nine dingoes were initially presented with the whistle; however, only one adult male responded as if the whistle was aversive. Seven of the nine dingoes were later presented with a whistle and treatment stimuli together. None of the seven dingoes were repelled during any air horn treatment trials; however, six of seven dingoes (all juveniles) were repelled by the water pistol stimulus. Although a water pistol was effective at repelling young dingoes on many occasions, responses between individuals were inconsistent. Results from this pilot study suggest that a water pistol stimulus may offer some protection as a repellent to close approaches by young dingoes, particularly if enhanced with a mild irritant.

Wild predators that attack people represent a significant challenge to the management authorities charged with conserving populations whilst minimising human safety risk. Fraser Island is home to an iconic population of dingoes (Canis dingo). However, conflict stemming from negative human–dingo interactions (incidents), some resulting in serious human injury and in one case, a fatality, is an ongoing concern. In an effort to highlight important factors influencing incident dynamics, we investigated the most serious incident reports gathered by the Queensland Parks and Wildlife Service for the period 2001–15. We found a consistent pattern of incidents peaking in March/April and also July, corresponding with dingo breeding and whelping seasons (respectively). Monthly vehicle permit numbers (a proxy for visitation) were not positively correlated with incident rates, except during the breeding season. Male dingoes, particularly subadult males, featured heavily in incidents. Despite the fatality being highly publicised and the advent of copious on-site warning messages and other management interventions, serious incidents continue to occur annually, including some involving children. This suggests that risks are either not always understood, or are otherwise being ignored. While our results demonstrate that dingoes generally pose minimal risk to humans, some risk remains, particularly where poorly supervised children are concerned.

Canids are generally considered to be ambush predators, but in island ecosystems adaptability and flexibility are essential for survival. Dingoes (Canis lupus dingo) attack and kill their prey in a variety of ways including utilising waterbodies. Here I document the drowning of an adult short-beaked echidna (Tachyglossus aculeatus) before consumption by a dingo using the coastal surf beach intertidal to shallow subtidal area on the eastern coast of Fraser Island (K’gari), highlighting an innovative prey-handling technique.

In the absence of an apex predator, irruptive herbivores suppress grass seed production: Implications for small granivores

Abstract AimThe primacy of top‐down (consumption) and bottom‐up effects (primary productivity) as forces structuring ecological communities is a controversial topic. The exploitation ecosystems hypothesis (EEH) was invoked to explain biogeographical trends in plant and consumer biomass, and differs from the top‐down/bottom‐up dichotomy by predicting that the relative strength of these processes will vary along gradients of primary productivity. Here we test the prediction of the EEH that herbivore biomass should increase with increasing primary productivity where predators are rare, but show a negligible response to primary productivity where predators are common due to population regulation by predators.LocationBoreal and temperate regions of North America and Eurasia, and deserts of Australia.Time period1970–2016.Major taxa studiedCervids and kangaroos.MethodsWe obtained abundance indices of cervids at 42 locations from the literature and conducted spotlight surveys at 27 locations to derive estimates of kangaroo abundance. For analyses, herbivore abundances were converted to biomass per km2. We tested our prediction using linear mixed effects models.ResultsHerbivore biomass showed divergent responses to increasing primary productivity and the abundance of canid predators (grey wolves, Canis lupus/dingoes, Canis dingo). The slope of the relationship between herbivore biomass and net primary productivity did not differ between Australia and the northern boreal and temperate regions. Herbivore biomass increased in response to primary productivity where canid predators were rare, but showed muted responses to increasing productivity where canid predators were common.Main conclusionsCanid predators have strong suppressive effects on herbivore biomass that scale with primary productivity. Our study shows that the EEH has wide application to canid‐predator–herbivore dynamics and may be relevant to the management of herbivores because it can provide an indication of how herbivore biomass and densities may vary in relation to ecosystem productivity and the presence and absence of canid predators.

Intraspecific conflict is an important process structuring carnivore populations. However, few data are available describing the precise mode of killing used by carnivores, especially medium-sized carnivores that can exhibit behaviours typically associated with either smaller or larger species. From records of free-ranging Australian dingoes killed during intraspecific fighting, we describe the types, location and frequency of injuries sustained, to assist in identifying killing behaviours common to medium-sized carnivores, or mesopredators. Observed injuries included superficial minor cuts and other wounds, deep punctures (bite marks or holes), severe lacerations to internal organs, tissue bruising and crushing, mutilation of muscle tissue, perforation of the chest and abdominal cavities, and a variety of bone fractures. The dingoes in this study predominately died from gross internal haemorrhaging caused by crushing bites coupled with vigorous shaking to the head, throat, neck and ventral chest areas. Our data demonstrate that dingoes used a ‘bite and shake’ mode of killing. This killing behaviour is dissimilar to those exhibited by large carnivores, but is consistent with behaviours shown by other medium-sized carnivores.

Fear of predation is a universal motivator. Because predators hunt using stealth and surprise, there is a widespread ability among prey to assess risk from chemical information-scents-in their environment. Consequently, scents often act as particularly strong modulators of memory and emotions. Recent advances in ecological research and analytical technology are leading to novel ways to use this chemical information to create effective attractants, repellents and anti-anxiolytic compounds for wildlife managers, conservation biologists and health practitioners. However, there is extensive variation in the design, results, and interpretation of studies of olfactory-based risk discrimination. To understand the highly variable literature in this area, we adopt a multi-disciplinary approach and synthesize the latest findings from neurobiology, chemical ecology, and ethology to propose a contemporary framework that accounts for such disparate factors as the time-limited stability of chemicals, highly canalized mechanisms that influence prey responses, and the context within which these scents are detected (e.g. availability of alternative resources, perceived shelter, and ambient physical parameters). This framework helps to account for the wide range of reported responses by prey to predator scents, and explains, paradoxically, how the same individual predator scent can be interpreted as either safe or dangerous to a prey animal depending on how, when and where the cue was deposited. We provide a hypothetical example to illustrate the most common factors that influence how a predator scent (from dingoes, Canis dingo) may both attract and repel the same target organism (kangaroos, Macropus spp.). This framework identifies the catalysts that enable dynamic scents, odours or odorants to be used as attractants as well as deterrents. Because effective scent tools often relate to traumatic memories (fear and/or anxiety) that cause future avoidance, this information may also guide the development of appeasement, enrichment and anti-anxiolytic compounds, and help explain the observed variation in post-traumatic-related behaviours (including post-traumatic stress disorder, PTSD) among diverse terrestrial taxa, including humans.

The trophic cascades concept may constrain Australian dingo reintroduction experiments: A response to Newsome et al. (2017)

Apex predator extirpation has been identified as a key driver of biodiversity losses. The mesopredator release hypothesis (MRH) predicts that reduced abundance of apex predators results in an increase in the abundance and predatory impact of mesopredators. Here we test predictions made according to the MRH that an apex predator, the dingo (Canis dingo), benefits a small ground-nesting bird, the little button-quail (Turnix velox), by reducing the abundance of introduced mesopredators, the red fox (Vulpes vulpes) and feral cat (Felis catus). We also examined an alternative hypothesis that herbivore grazing negatively affects little button-quail abundance by reducing ground cover. To test our predictions we compared dingo, mesopredator, quail, herbivore and ground cover abundances and predator diets over a 25 month period and across a 10,000 km2 region encompassing areas where dingoes were common and rare, pastoral properties, and conservation reserves. Little button-quails were primarily observed where dingoes were common and foxes rare. Cats were detected at low numbers throughout the sample area irrespective of the index abundance of little button-quails, dingoes or foxes. Birds occurred less frequently in dingo than fox or cat scats. Ground cover and herbivore grazing activity were poor correlates of little button-quail abundance. Our results are consistent with the hypothesis that apex predators’ mesopredator-suppressive effects translate to population-level benefits for a ground-nesting bird. Positive associations between the abundances of dingoes and small-prey species suggests that positive management of dingoes could be incorporated into broad-scale biodiversity conservation programs as a strategy to alleviate the predatory impacts of foxes.

Wallach, Arian D., Ramp, Daniel, O'Neill, Adam J. (2017): Cattle mortality on a predator-friendly station in central Australia. Journal of Mammalogy 98 (1): 45-52, DOI: 10.1093/jmammal/gyw156, URL: http://dx.doi.org/10.1093/jmammal/gyw156

Apex predators are subject to lethal control in many parts of the world to minimize their impacts on human industries and livelihoods. Diverse communities of smaller predators—mesopredators—often remain after apex predator removal. Despite concern that these mesopredators may be 'released' in the absence of the apex predator and exert negative effects on each other and on co-occurring prey, these interactions have been little studied. Here, we investigate the potential effects of competition and intraguild predation between red foxes (Vulpes vulpes) and feral cats (Felis catus) in south-eastern Australia where the apex predator, the dingo (Canis dingo), has been extirpated by humans. We predicted that the larger fox would dominate the cat in encounters, and used a fox-removal experiment to assess whether foxes affect cat abundance, diet, home-range and habitat use. Our results provide little indication that intraguild predation occurred or that cats responded numerically to the fox removal, but suggest that the fox affects some aspects of cat resource use. In particular, where foxes were removed cats increased their consumption of invertebrates and carrion, decreased their home range size and foraged more in open habitats. Fox control takes place over large areas of Australia to protect threatened native species and agricultural interests. Our results suggest that fox control programmes could lead to changes in the way that cats interact with co-occurring prey, and that some prey may become more vulnerable to cat predation in open habitats after foxes have been removed. Moreover, with intensive and more sustained fox control it is possible that cats could respond numerically and alter their behaviour in different ways to those documented herein. Such outcomes need to be considered when estimating the indirect impacts of fox control. We conclude that novel approaches are urgently required to control invasive mesopredators at the same time, especially in areas where apex predators are absent.

This paper describes the first known records of the Eyrean Grasswren Amytornis goyderi from New South Wales (NSW). These observations were made on 3 April 2016 just inside the border adjacent to South Australia and were clearly on the margins of the species’ range. The habitats noted at the time of the observations were of plant species found throughout the Strzelecki Desert, but did not include Sandhill Canegrass Zygochloa paradoxa (often quoted as a key habitat for the species), which was absent from the immediate vicinity. It is suggested that the low numbers of Eyrean Grasswrens in the Strzelecki Desert in NSW might be a consequence of overgrazing by livestock and Red Kangaroos Osphranter rufus , the latter influenced by the culling of Dingoes Canis dingo , as well as the increased predation on smaller birds and mammals by Red Foxes Vulpes vulpes .

Introducing a new or extirpated species to an ecosystem is risky, and managers need quantitative methods that can predict the consequences for the recipient ecosystem. Proponents of keystone predator reintroductions commonly argue that the presence of the predator will restore ecosystem function, but this has not always been the case, and mathematical modeling has an important role to play in predicting how reintroductions will likely play out. We devised an ensemble modeling method that integrates species interaction networks and dynamic community simulations and used it to describe the range of plausible consequences of 2 keystone-predator reintroductions: wolves (Canis lupus) to Yellowstone National Park and dingoes (Canis dingo) to a national park in Australia. Although previous methods for predicting ecosystem responses to such interventions focused on predicting changes around a given equilibrium, we used Lotka-Volterra equations to predict changing abundances through time. We applied our method to interaction networks for wolves in Yellowstone National Park and for dingoes in Australia. Our model replicated the observed dynamics in Yellowstone National Park and produced a larger range of potential outcomes for the dingo network. However, we also found that changes in small vertebrates or invertebrates gave a good indication about the potential future state of the system. Our method allowed us to predict when the systems were far from equilibrium. Our results showed that the method can also be used to predict which species may increase or decrease following a reintroduction and can identify species that are important to monitor (i.e., species whose changes in abundance give extra insight into broad changes in the system). Ensemble ecosystem modeling can also be applied to assess the ecosystem-wide implications of other types of interventions including assisted migration, biocontrol, and invasive species eradication.