Guy Ballard

Communicating Ecology Through Art: What Scientists Think

Many environmental issues facing society demand considerable public investment to reverse. However, this investment will only arise if the general community is supportive, and community support is only likely if the issues are widely understood. Scientists often find it difficult to communicate with the general public. The role of the visual and performing arts is often overlooked in this regard, yet the arts have long communicated issues, influenced and educated people, and challenged dominant paradigms. To assess the response of professional ecologists to the role of the arts in communicating science, a series of constructed performances and exhibitions was integrated into the program of a national ecological conference over five days. At the conclusion of the conference, responses were sought from the assembled scientists and research students toward using the arts for expanding audiences to ecological science. Over half the delegates said that elements of the arts program provided a conducive atmosphere for receiving information, encouraged them to reflect on alternative ways to communicate science, and persuaded them that the arts have a role in helping people understand complex scientific concepts. A sizeable minority of delegates (24%) said they would consider incorporating the arts in their extension or outreach efforts. Incorporating music, theatre, and dance into a scientific conference can have many effects on participants and audiences. The arts can synthesize and convey complex scientific information, promote new ways of looking at issues, touch peoples emotions, and create a celebratory atmosphere, as was evident in this case study. In like manner, the visual and performing arts should be harnessed to help extend the increasingly unpalatable and urgent messages of global climate change science to a lay audience worldwide.

Dietary niche overlap of free-roaming dingoes and domestic dogs: the role of human-provided food

Abstract As both companion animals and opportunistic predators, dogs (Canis lupus spp.) have had a long and complex relationship with humans. In Australia, the dingo (C. l. dingo) was introduced 4,000 years ago and, other than humans, is now the continents top mammalian predator. Domestic dogs (C. l. familiaris) were introduced by Europeans more recently and they interbreed with dingoes. This hybridization has caused growing concern about the roles that domestic dogs and dingoes play in shaping ecosystem processes. There is also considerable debate about whether anthropogenic environmental changes can alter the ecological roles of dingoes. We used scat analysis to test whether the dingo, as the longer-established predator, occupies a different dietary niche from that of free-roaming domestic dogs, irrespective of human influence. Our results demonstrate considerable dietary overlap between dingoes and domestic dogs in areas where humans provide supplementary food, providing evidence against our hypothesis. However, the consumption by dingoes of a greater diversity of prey, in association with historical differences in the interactions between dingoes and humans, suggests a partial separation of their dietary niche from that of domestic dogs. We conclude that anthropogenic changes in resource availability could prevent dingoes from fulfilling their trophic regulatory or pre-European roles. Effective management of human-provided food is therefore required urgently to minimize the potential for subsidized populations of dingoes and domestic dogs to negatively affect co-occurring prey.

Are we getting the full picture? Animal responses to camera traps and implications for predator studies.

Abstract Camera trapping is widely used in ecological studies. It is often considered nonintrusive simply because animals are not captured or handled. However, the emission of light and sound from camera traps can be intrusive. We evaluated the daytime and nighttime behavioral responses of four mammalian predators to camera traps in road‐based, passive (no bait) surveys, in order to determine how this might affect ecological investigations. Wild dogs, European red foxes, feral cats, and spotted‐tailed quolls all exhibited behaviors indicating they noticed camera traps. Their recognition of camera traps was more likely when animals were approaching the device than if they were walking away from it. Some individuals of each species retreated from camera traps and some moved toward them, with negative behaviors slightly more common during the daytime. There was no consistent response to camera traps within species; both attraction and repulsion were observed. Camera trapping is clearly an intrusive sampling method for some individuals of some species. This may limit the utility of conclusions about animal behavior obtained from camera trapping. Similarly, it is possible that behavioral responses to camera traps could affect detection probabilities, introducing as yet unmeasured biases into camera trapping abundance surveys. These effects demand consideration when utilizing camera traps in ecological research and will ideally prompt further work to quantify associated biases in detection probabilities.

Effects of Sex and Reproductive State on Interactions between Free-Roaming Domestic Dogs

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 communitys 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.

Cooperative hunting between humans and domestic dogs in eastern and northern Australia

Abstract Context. Dogs aid hunters in many parts of Australia. Because of close proximity, transfer of zoonotic disease between hunters, hunting dogs and wildlife can, and does, occur. Knowledge about cooperative hunting between humans and domestic dogs and interactions with wildlife in Australia is limited, but is necessary to improve zoonotic-risk mitigation strategies. Aims. We aimed to describe the frequency and geographic distribution of hunting with dogs, and to document interactions between them and wildlife that could contribute to zoonosis transmission. Methods. Australian hunters were invited via web-based hunting forums, hunting supply stores and government agency communications to complete an online questionnaire about their hunting activities. Key results. Most of the 440 responding hunters resided on Australia’s eastern coast. Pest animal management and recreation were their primary drivers for hunting with dogs. Most hunters used one or two dogs, and travelled ≥500u2009km to target feral pigs, rabbits, birds and deer. Almost a quarter of respondents (Nu2009=u2009313) had lost a dog while hunting, but most (93%, Nu2009=u200961) were reportedly recovered within a few hours. Half the respondents indicated that they had encountered wild dogs while hunting, and reported a range of consequences from non-contact interactions through to attacks on the hunting dog or hunter. Conclusions. Australian hunters frequently used dogs to assist in hunts of birds and introduced mammals, particularly where access was difficult because of rough terrain or thick vegetation. Interactions between hunters and non-target animals such as wild dogs were common, providing potential pathways for the spread of diseases. Furthermore, hunting expeditions >500u2009km from the point of residence occurred regularly, which could facilitate translocation of important zoonotic diseases between states and the creation of disparate foci of disease spread, even into highly populated areas. Implications. Our improved understanding of hunting-dog use in Australia is essential to quantify the risk of disease transmission between wildlife and humans, identify transmission pathways and devise management plans to quash disease outbreaks. To promote rapid detection of exotic diseases, hunters should be encouraged to report unusual wildlife behaviour and interactions with their dogs.

Invasive species and their impacts on agri-ecosystems: issues and solutions for restoring ecosystem processes

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.

Contact rates of wild-living and domestic dog populations in Australia: a new approach

Dogs (Canis familiaris) can transmit pathogens to other domestic animals, humans and wildlife. Both domestic and wild-living dogs are ubiquitous within mainland Australian landscapes, but their interactions are mostly unquantified. Consequently, the probability of pathogen transfer among wild-living and domestic dogs is unknown. To address this knowledge deficit, we established 65 camera trap stations, deployed for 26,151 camera trap nights, to quantify domestic and wild-living dog activity during 2xa0years across eight sites in north-east New South Wales, Australia. Wild-living dogs were detected on camera traps at all sites, and domestic dogs recorded at all but one. No contacts between domestic and wild-living dogs were recorded, and limited temporal overlap in activity was observed (32xa0%); domestic dogs were predominantly active during the day and wild-living dogs mainly during the night. Contact rates between wild-living and between domestic dogs, respectively, varied between sites and over time (range 0.003–0.56 contacts per camera trap night). Contact among wild-living dogs occurred mainly within social groupings, and peaked when young were present. However, pup emergence occurred throughout the year within and between sites and consequently, no overall annual cycle in contact rates could be established. Due to infrequent interactions between domestic and wild-living dogs, there are likely limited opportunities for pathogen transmission that require direct contact. In contrast, extensive spatial overlap of wild and domestic dogs could facilitate the spread of pathogens that do not require direct contact, some of which may be important zoonoses.

Home range and activity patterns measured with GPS collars in spotted-tailed quolls

Abstract. The spotted-tailed quoll (Dasyurus maculatus) is the largest marsupial carnivore on mainland Australia. It usually occurs at relatively low population densities and its cryptic nature makes it exceedingly difficult to observe in its natural habitat. On the mainland the species is also listed as nationally endangered and more information is needed to direct any meaningful conservation effort. In this study we aimed to elucidate quolls’ spatial requirements and activity patterns using GPS collars on 10 males and 4 females. Quolls were predominantly nocturnal but some individuals showed pronounced daytime activity. There was no apparent seasonal shift in the timing of activity. The movement of quolls appeared to be confined to home ranges that were relatively large for predators of their size. Furthermore, males used home ranges about three times as large as that of the smaller females. There appeared to be some spatial segregation between not only females, which have been considered territorial, but also males. Overall, it is likely that the larger areas used by males is partly caused by the sexual dimorphism in body mass that entails differences in prey requirements and spectrum, but probably is also a function of a promiscuous mating system. All of these could explain the observed more unidirectional movement and larger distances travelled per day by males.

How long is a dingo's tale?: Impacts of sampling design on our understanding of dingo ecology

ABSTRACT The temporal scale of many studies of dingo ecology is limited by human and physical resources, often constrained by funding cycles. Consequently, research has been skewed towards short-term, snapshot investigations undertaken at a spatial scale that is unrelated to dingo home range size, space use and life history. In turn, the certainty of ecological conclusions is constrained. Here we discuss the difficulties and limitations of much of the dingo research previously undertaken, including our own, and discuss the benefits of long-term data sets for elucidating ecological processes involving dingoes. We provide explanatory examples where current technological advances provide opportunities for improved monitoring and certainty around conclusions.

Techniques and practices of Australian pest animal trappers

We conducted a survey of trappers to gather baseline information on the trapping methods and humane practices used in Australia, the types of traps being used, and the attitudes of trappers. Respondents indicated that they mostly trapped wild dogs and foxes with feral cats as by-catch; rabbits were trapped to a lesser degree. Respondents favoured Jake and Victor #3 traps for the capture of wild dogs. Victor #1.5, #3 and Jake traps were also favoured for capturing foxes and feral cats. Although some trappers placed up to four traps together in a set, a single trap per set was the most commonly reported approach. Trap maintenance varied between individuals but most said they checked traps for problems during deployment. Respondents preferred the term ‘rubber jawed traps’ over the plethora of other synonyms in current use. All respondents were cognisant of animal welfare requirements but their acceptance and adoption of related trapping methods varied. Most did not believe that licensing was required to govern trapping practices in Australia. Euthanasia was most commonly undertaken by shooting the captured animal in the head, although rabbits and some non-target animals were reportedly dispatched by a blow to the head. This is the first survey of Australian trappers and provides a benchmark for understanding trapping culture, practices and practitioner expectations so these can be considered in policy development and implementation.