Scott Carver

University of Tasmania · Department of Biological Sciences

Most pathogens infect more than one host species, and given infection, the individual-level impact they have varies among host species. Nevertheless, variation in individual-level impacts of infection remains poorly characterised. Using the impactful and host-generalist ectoparasitic mite Sarcoptes scabiei (causing sarcoptic mange), we assessed ind...

1. Understanding the spatial dynamics and drivers of wildlife pathogens is constrained by sampling logistics, with implications for advancing the field of landscape epidemiology and targeted allocation of management resources. However, visually apparent wildlife diseases, when combined with remote-surveillance and distribution modelling technologie...

Feline Immunodeficiency Virus (FIV) causes progressive immune dysfunction in cats similar to human immunodeficiency virus (HIV) in humans. Although combination antiretroviral therapy (cART) is effective against HIV, there is no definitive therapy to improve clinical outcomes in cats with FIV. This study therefore evaluated pharmacokinetics and clin...

Landscape epidemiology provides a valuable framework to interpret, predict, and manage spatiotemporal patterns of disease. Yet, owing to the difficulty of detecting pathogen occurrence in free-ranging wildlife, disentangling the factors driving disease dynamics remains a considerable challenge, particularly at fine spatial scales. Here, we investig...

Sarcoptes scabiei is the microscopic burrowing mite responsible for sarcoptic mange, which is reported in approximately 150 mammalian species. In Australia, sarcoptic mange affects a number of native and introduced wildlife species, is particularly severe in bare-nosed wombats (Vombatus ursinus) and an emerging issue in koala and quenda. There are...

Understanding the spread of pathogens through the environment is critical to a fuller comprehension of disease dynamics. However, many mathematical models of disease dynamics ignore spatial effects. We seek to expand knowledge around the interaction between the bare-nosed wombat (Vombatus ursinus) and sarcoptic mange (etiologic agent Sarcoptes scab...

Spatially heterogeneous landscape factors such as urbanisation can have substantial effects on the severity and spread of wildlife diseases. However, research linking patterns of pathogen transmission to landscape features remains rare. Using a combination of phylogeographic and machine learning approaches, we tested the influence of landscape and...

10 Pellet feces are generated by a number of animals important to science or agriculture, including 11 mice, rats, goats, and wombats. Understanding the factors that lead to fecal shape may provide 12 a better understanding of animal health and diet. In this combined experimental and theoretical 13 study, we test the hypothesis that the dynamics of...

Interventions against infectious disease in wildlife are increasingly necessary but remain problematic. Dissimilar to public and domestic animal health, pharmacological interventions (PIs) are rarely used against disease in wildlife populations. However, drugs can combat a range of pathogen‐types while aligning with positive ethical, epidemiologica...

Background Sarcoptes scabiei is globally distributed and one of the most impactful mammalian ectoparasites. Sarcoptic mange, caused by infection with S. scabiei , causes disruption of the epidermis and its bacterial microbiota, but its effects on host fungal microbiota and on the microbiota of marsupials in general have not been studied. Here, we (...

Identifying drivers of transmission—especially of emerging pathogens—is a formidable challenge for proactive disease management efforts. While close social interactions can be associated with microbial sharing between individuals, and thereby imply dynamics important for transmission, such associations can be obscured by the influences of factors s...

There are multiple demands for the development of effective and sustainable disease management practices in wildlife, but solutions are widely lacking. In this perspective we focus on the need to structure research to support advancement toward enhanced wildlife disease control solutions. We concentrate on the need for improved integration between...

Microbial changes with sarcoptic mange disease progression in free-ranging BNWs in Tasmania.

Predicting what factors promote or protect populations from infectious disease is a fundamental epidemiological challenge. Social networks, where nodes represent hosts and edges represent direct or indirect contacts between them, are key to quantifying these aspects of infectious disease dynamics. However, understanding the complex relationships be...

Background Sarcoptes scabiei is one of the most impactful mammalian parasites. There has been much research on immunological and clinical pathological changes associated with S. scabiei parasitism across a range of host species. This rich body of literature is complex, and we seek to bring that complexity together in this study. We first (1) synthe...

Sarcoptic scabiei is an invasive parasitic mite that negatively impacts wombats, causing sarcoptic mange disease, characterized by alopecia, intense pruritus, hyperkeratosis, and eventual mortality. Evidence suggests that wombats may be unable to recovery from infection without the assistance of treatments. Transdermal drug delivery is considered t...

We report the physical characteristics of rumpwear in the Australian common ringtail possum, Pseudocheirus peregrinus. Rumpwear presents as varying grades of hair breakage and dermatitis on the lumbosacral region. This condition has been reported in Trichosurus spp. (brushtail possums) previously, but never in P. peregrinus. The etiology remains po...

Rehabilitation of disused mine sites through stabilisation and botanical restoration is ecologically important, but metal transfer pathways to colonising wildlife are often less understood and have never been studied in marsupials. The rehabilitated Royal George tin mine tailings and colonisation by bare-nosed wombats (Vombatus ursinus) represented...

Most herbivorous mammals have symbiotic microbes living in their gastrointestinal tracts that help with harvesting energy from recalcitrant plant fibre. The bulk of research into these microorganisms has focused on samples collected from faeces, representing the distal region of the gastrointestinal (GI) tract. However, the GI tract in herbivorous...

A recent article published in Parasitology Research describes the use of high-dose moxidectin (Cydectin®) by wildlife carers for the treatment of sarcoptic mange in bare-nose wombats (Vombatus ursinus). We provide additional perspectives on this topic, including consideration of the pharmacokinetics, mode of action and efficacy of moxidectin. The v...

Hunting can fundamentally alter wildlife population dynamics but the consequences of hunting on pathogen transmission and evolution remain poorly understood. Here, we present a study that leverages a unique landscape-scale quasi-experiment coupled with pathogen-transmission tracing, network simulation and phylodynamics to provide insights into how...

ContextDisease is increasingly becoming a driver of wildlife population declines and an extinction risk. Vaccines are one of the most successful health interventions in human history, but few have been tested for mitigating wildlife disease. The transmissible cancer, devil facial tumour disease (DFTD), triggered the Tasmanian devil’s (Sarcophilus h...

Some pathogens sustain transmission in multiple different host species, but how this epidemiologically important feat is achieved remains enigmatic. Sarcoptes scabiei is among the most host generalist and successful of mammalian parasites. We synthesize pathogen and host traits that mediate sustained transmission and present cases illustrating thre...

Resource competition is an important interaction that can structure ecological communities, but is difficult to demonstrate in nature, and rarely demonstrated for large mammals including marsupials. We analysed 10 years of population survey data to investigate resource competition between bare-nosed wombats (Vombatus ursinus) and eastern grey kanga...

With thousands of vertebrate species now threatened with extinction, there is an urgent need to understand and mitigate the causes of wildlife collapse. Rails (Aves: Rallidae), being the most extinction-prone bird family globally, and with one-third of extant rail species now threatened or near threatened, are an emphatic case in point. Here, we un...

We introduce a new R package ‘MrIML’ (‘Mister iml’; Multi-response Interpretable Machine Learning). MrIML provides a powerful and interpretable framework that enables users to harness recent advances in machine learning to quantify multi-locus genomic relationships, to identify loci of interest for future landscape genetics studies, and to gain new...

Some of the most important pathogens affecting wildlife are transmitted indirectly via the environment. Yet the environmental stages of pathogens are often poorly understood, relative to infection in the host, making this an important research frontier. Sarcoptic mange is a globally widespread disease caused by the parasitic mite Sarcoptes scabiei....

Background: Sarcoptic mange causes significant animal welfare and occasional conservation concerns for bare-nosed wombats (Vombatus ursinus) throughout their range. To date, in situ chemotherapeutic interventions have involved macrocytic lactones, but their short duration of action and need for frequent re-administration has limited treatment succe...

Some countries have been crippled by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic while others have emerged with few infections and fatalities; the factors underscoring this macro-epidemiological variation is one of the mysteries of this global catastrophe. Variation in immune responses influence SARS-CoV-2 transmission...

Understanding species’ distribution, population trends, and the significance of threatening processes are central to the effective conservation and management of wildlife. The island state of Tasmania, Australia, is home to two of the three extant subspecies of common wombat Vombatus ursinus ursinus and V. u. tasmaniensis, both endemic to the state...

Sarcoptic mange is an infectious disease impacting over 100 mammalian species around the world, including Australia’s common wombat (Vombatus ursinus). A 94% decline in a localised population attributed to mange has raised concerns for the status of the two subspecies endemic to the island state of Tasmania, Australia. We provide the first broad-sc...

Causative disease and stress agents which manifest as dermatitis in mammals have varying effects on individual animals, from benign irritation and inflammation, to causing morbidity and even mortality. Bacteria, viruses and ectoparasites are all potential causes of dermatitis, and it can be exacerbated by various environmental, genetic and social f...

Hunting can fundamentally alter wildlife population dynamics, but the consequences of hunting on pathogen transmission and evolution remain poorly understood. Here we present a study that leverages a unique landscape-scale experiment coupled with pathogen transmission tracing, network simulation and phylodynamics to provide insights into how huntin...

In this study we evaluate the design and efficacy of Wombot, an exploratory robot used to study environmental conditions within wombat burrows. Our purpose-built robot traverses through the difficult terrain present in wombat burrows whilst facilitating placement and retrieval of environmental data loggers. Our preliminary results suggest that the...

Background Most herbivorous mammals have symbiotic microbes living in their gastrointestinal tracts that help with harvesting energy from recalcitrant plant fibre. The bulk of research into these microorganisms has focused on samples collected from faeces, representing the distal region of the gastrointestinal (GI) tract. However, the GI tract in h...

Most herbivorous mammals have symbiotic microbes living in their gastrointestinal tracts that help with harvesting energy from recalcitrant plant fibre. The bulk of research into these microorganisms has focused on samples collected from faeces, representing the distal region of the gastrointestinal (GI) tract. However, the GI tract in herbivorous...

Sarcoptic mange, a skin infestation caused by the mite Sarcoptes scabiei, is an emerging disease for some species of wildlife, potentially jeopardizing their welfare and conservation. Sarcoptes scabiei has a near‐global distribution facilitated by its forms of transmission and use of a large diversity of host species (many of those with broad geogr...

Background Statistical models are regularly used in the forecasting and surveillance of infectious diseases to guide public health. Variable selection assists in determining factors associated with disease transmission, however, often overlooked in this process is the evaluation and suitability of the statistical model used in forecasting disease t...

An amendment to this paper has been published and can be accessed via the original article.

Geographically widespread species present challenges for conservation assessment. We used long‐term spotlight surveys to assess spatiotemporal dynamics of bare‐nosed wombats (Vombatus ursinus), encompassing 34 years of surveys for the Tasmanian mainland sub‐species (V. u. tasmaniensis, 1985–2018) and 25 years for the Flinders Island sub‐species (V....

Parasite success is typically dependent upon a close relationship with one or more hosts; therefore, attributes of parasitic infection have the potential to provide indirect details of host natural history and are biologically relevant to animal conservation. Characterization of parasite infections has been useful in delineating host populations an...

The bare-nosed wombat (Vombatus ursinus) is a fossorial, herbivorous, Australian marsupial, renowned for its cubic feces. However, the ability of the wombat's soft intestine to sculpt flat faces and sharp corners in feces is poorly understood. In this combined experimental and numerical study, we show one mechanism for the formation of corners in a...

With thousands of vertebrate species now threatened with extinction, there is an urgent need to understand and mitigate the causes of wildlife collapse. As distinct evolutionary clades can follow different routes to endangerment, there is value in taxon-specific analyses when assessing species' vulnerability to threats and identifying gaps in conse...

Identifying drivers of transmission prior to an epidemic - especially of an emerging pathogen - is a formidable challenge for proactive disease management efforts. We tested a novel approach in the Florida panther, hypothesizing that apathogenic feline immunodeficiency virus (FIV) transmission could predict transmission dynamics for pathogenic feli...

Background Sarcoptic mange causes significant animal welfare and occasional conservation concerns for bare-nosed wombats ( Vombatus ursinus ) throughout their range. To date, in situ chemotherapeutic interventions have involved macrocytic lactones, but their short duration of action and need for frequent re-administration has limited treatment succ...

Urban expansion can fundamentally alter wildlife movement and gene flow, but how urbanization alters pathogen spread is poorly understood. Here, we combine high resolution host and viral genomic data with landscape variables to examine the context of viral spread in puma ( Puma concolor ) from two contrasting regions: one bounded by the wildland ur...

How hosts become exposed to environmentally transmitted pathogens has significant consequences for their dynamics and control, including conservation-critical cases. We investigate whether dynamics of the globally important parasite Sarcoptes scabiei are strongly influenced by transmission. We compare two transmission models, based on mange transmi...

We introduce a new R package ‘MrIML’ (Multi-response Interpretable Machine Learning). MrIML provides a powerful and interpretable framework that enables users to harness recent advances in machine learning to map multi-locus genomic relationships, to identify loci of interest for future landscape genetics studies and to gain new insights into adapt...

Disease is increasingly becoming a driver of wildlife population declines and extinction risk. Vaccines have been one of the most successful health interventions in human history, but few have been tested for mitigating wildlife disease. The transmissible cancer, devil facial tumour disease (DFTD), triggered the Tasmanian devil’s ( Sarcophilus harr...

Since spilling over into humans, SARS-CoV-2 has rapidly spread across the globe, accumulating significant genetic diversity. The structure of this genetic diversity, and whether it reveals epidemiological insights, are fundamental questions for understanding the evolutionary trajectory of this virus. Here we use a recently developed phylodynamic ap...

Recreational use of public land is high and rising. Thus, it is critical to understand the dynamics of land use at the wildland–urban interface so managers can simultaneously meet varying human needs while mitigating environmental impacts caused by recreationists and their canine companions. Using motion-activated camera surveys along official trai...

Background: Chlamydial disease is a major factor negatively affecting koala populations. Vaccination is a promising management option that would result in immune-mediated protection against disease. Measuring and assessing vaccine efficacy can be challenging owing to both direct and indirect interactions caused by vaccination. In this study, we inv...

Background: Wildlife species carry a remarkable diversity of trypanosomes. The detection of trypanosome infection in native Australian fauna is central to understanding their diversity and host-parasite associations. The implementation of total RNA sequencing (meta-transcriptomics) in trypanosome surveillance and diagnosis provides a powerful meth...

Urban development has major impacts on connectivity among wildlife populations and is thus likely an important factor shaping pathogen transmission in wildlife. However, most investigations of wildlife diseases in urban areas focus on prevalence and infection risk rather than potential effects of urbanisation on transmission itself. Feline immunode...

Temperate Australian saltmarshes, including those in the southern island state of Tasmania, are considered to be a threatened ecological community under Australian federal legislation. There is a need to improve our understanding of the ecological components, functional relationships and threatening processes of Tasmanian coastal saltmarshes and di...

Since spilling over into humans, SARS-CoV-2 has rapidly spread across the globe, accumulating significant genetic diversity. The structure of this genetic diversity, and whether it reveals epidemiological insights, are fundamental questions for understanding the evolutionary trajectory of this virus. Here we use a recently developed phylodynamic ap...

Epidemiological studies commonly monitor host population density but rarely account for how transmission dynamics might be influenced by changes in spatial and social organization that arise from high mortality altering population demography. Devil facial tumour disease (DFTD), a novel transmissible cancer, caused almost 100% mortality of its singl...

Saltmarsh breeding mosquitoes are an important source of vectors for arboviral transmission. In southern Australia, the most prominent vector borne disease, Ross River virus (Togaviridae: Alphavirus) (RRV), is transmitted by the saltmarsh mosquito (Diptera: Culicidae) Aedes camptorhynchus (Thomson). However, the factors driving the abundance of thi...

Does the structure and connectivity of host populations influence the dynamics and evolution of their pathogens? This topical question is the essence of research investigating the ecology of a Pteropus fruit bat and it’s zoonotic Nipah virus (NiV) published by Olival et al. (2019) in this issue of Molecular Ecology. Questioned less overtly, but non...

Feline foamy virus (FFV) is a contact-dependent retrovirus forming chronic, largely apathogenic, infections in domestic and wild felid populations worldwide. Given there is no current ‘gold standard’ diagnostic test for FFV, efforts to elucidate the ecology and epidemiology of the virus may be complicated by unknown sensitivity and specificity of d...

The authors have withdrawn this preprint from Research Square

Background Disease is a major factor negatively affecting koala populations. Vaccination is a promising treatment option that would result in immune-mediated protection against disease. Measuring and assessing vaccine efficacy can be challenging owing to both direct and indirect interactions caused by vaccination. In this study, we investigate vacc...

Emerging viral outbreaks resulting from host switching is an area of continued scientific interest. Such events can result in disease epidemics or in some cases, clinically silent outcomes. These occurrences are likely relatively common and can serve as tools to better understand disease dynamics, and may result in changes in behavior, fecundity, a...

In most mammalian species, mothers must protect offspring from multiple sources of risk. In Australia, feral horses, Equus ferus caballus, have naturalized in many ecosystems, and foals are at risk from both predation by dingoes and sexually selected infanticide by nonpaternal stallions. This study tested maternal responses to these two forms of ri...

The northern hairy-nosed wombat (Lasiorhinus krefftii) is an iconic marsupial endemic to Australia, recognised globally for its status as the largest, herbivorous burrowing mammal. Owing to historical challenges, including anthropogenic conflict and environmental threats, the species was pushed to near extinction and was officially classified as Cr...

Dogs are often commensal with human settlements. In areas where settlements are adjacent to wildlife habitat, the management of dogs can affect risk of spillover of disease to wildlife. We assess dog husbandry practices, and measure the prevalence of Canine Distemper Virus (CDV) in dogs, in 10 villages in Nepal’s Annapurna Conservation Area (ACA),...

Introduction: Vaccine development research is proliferating making it difficult to determine the most promising vaccine candidates. Exemplary of this problem is vaccine development against Chlamydia, a pathogen of global public health and financial importance. Methods: We systematically extracted data from studies that included chlamydial load or h...