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Watts HE, Cornelius JM. Toward understanding the endocrine regulation of diverse facultative migration strategies. Horm Behav 2024; 158:105465. [PMID: 38061233 DOI: 10.1016/j.yhbeh.2023.105465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 02/05/2024]
Abstract
Migration is an important event in the annual cycle of many animals that facilitates the use of resources that vary across space and time. It can occur with regular and predictable timing, as in obligate migration, or with much greater flexibility, as in facultative migration. Most research aimed at understanding the endocrine mechanisms regulating the transition to a migratory stage has focused on obligate migration, whereas less is known about facultative forms of migration. One challenge for research into the endocrine regulation of facultative migration is that facultative migrations encompass a diverse array of migratory movements. Here, we present a framework to describe and conceptualize variation in facultative migrations that focuses on conditions at departure. Within the context of this framework, we review potential endocrine mechanisms involved in the initiation of facultative migrations in vertebrates. We first focus on glucocorticoids, which have been the subject of most research on the topic. We then examine other potential hormones and neurohormones that have received less attention, but are exciting candidates to consider. We conclude by highlighting areas where future research is particularly needed.
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Affiliation(s)
- Heather E Watts
- School of Biological Sciences, Washington State University, Pullman, WA 99164, USA; Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA.
| | - Jamie M Cornelius
- Department of Integrative Biology, Oregon State University, Corvallis, OR 97331, USA
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2
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Eby P, Peel AJ, Hoegh A, Madden W, Giles JR, Hudson PJ, Plowright RK. Pathogen spillover driven by rapid changes in bat ecology. Nature 2023; 613:340-344. [PMID: 36384167 PMCID: PMC9768785 DOI: 10.1038/s41586-022-05506-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 11/01/2022] [Indexed: 11/17/2022]
Abstract
During recent decades, pathogens that originated in bats have become an increasing public health concern. A major challenge is to identify how those pathogens spill over into human populations to generate a pandemic threat1. Many correlational studies associate spillover with changes in land use or other anthropogenic stressors2,3, although the mechanisms underlying the observed correlations have not been identified4. One limitation is the lack of spatially and temporally explicit data on multiple spillovers, and on the connections among spillovers, reservoir host ecology and behaviour and viral dynamics. We present 25 years of data on land-use change, bat behaviour and spillover of Hendra virus from Pteropodid bats to horses in subtropical Australia. These data show that bats are responding to environmental change by persistently adopting behaviours that were previously transient responses to nutritional stress. Interactions between land-use change and climate now lead to persistent bat residency in agricultural areas, where periodic food shortages drive clusters of spillovers. Pulses of winter flowering of trees in remnant forests appeared to prevent spillover. We developed integrative Bayesian network models based on these phenomena that accurately predicted the presence or absence of clusters of spillovers in each of the 25 years. Our long-term study identifies the mechanistic connections between habitat loss, climate and increased spillover risk. It provides a framework for examining causes of bat virus spillover and for developing ecological countermeasures to prevent pandemics.
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Affiliation(s)
- Peggy Eby
- School of Biological, Earth, and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia.,Centre for Planetary Health and Food Security, Griffith University, Nathan, Queensland, Australia.,Center for Large Landscape Conservation, Bozeman, MT, USA
| | - Alison J Peel
- Centre for Planetary Health and Food Security, Griffith University, Nathan, Queensland, Australia
| | - Andrew Hoegh
- Department of Mathematical Sciences, Montana State University, Bozeman, MT, USA
| | - Wyatt Madden
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA.,Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - John R Giles
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.,Institute for Health Metrics and Evaluation, University of Washington, Seattle, WA, USA
| | - Peter J Hudson
- Center for Infectious Disease Dynamics, Pennsylvania State University, State College, PA, USA
| | - Raina K Plowright
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA. .,Department of Public and Ecosystem Health, Cornell University, Ithaca, NY, USA.
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3
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Becker DJ, Eby P, Madden W, Peel AJ, Plowright RK. Ecological conditions predict the intensity of Hendra virus excretion over space and time from bat reservoir hosts. Ecol Lett 2023; 26:23-36. [PMID: 36310377 DOI: 10.1111/ele.14007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 03/09/2022] [Indexed: 12/27/2022]
Abstract
The ecological conditions experienced by wildlife reservoirs affect infection dynamics and thus the distribution of pathogen excreted into the environment. This spatial and temporal distribution of shed pathogen has been hypothesised to shape risks of zoonotic spillover. However, few systems have data on both long-term ecological conditions and pathogen excretion to advance mechanistic understanding and test environmental drivers of spillover risk. We here analyse three years of Hendra virus data from nine Australian flying fox roosts with covariates derived from long-term studies of bat ecology. We show that the magnitude of winter pulses of viral excretion, previously considered idiosyncratic, are most pronounced after recent food shortages and in bat populations displaced to novel habitats. We further show that cumulative pathogen excretion over time is shaped by bat ecology and positively predicts spillover frequency. Our work emphasises the role of reservoir host ecology in shaping pathogen excretion and provides a new approach to estimate spillover risk.
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Affiliation(s)
- Daniel J Becker
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, USA.,Department of Biology, University of Oklahoma, Norman, Oklahoma, USA
| | - Peggy Eby
- School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, Australia.,Centre for Planetary Health and Food Security, Griffith University, Queensland, Australia
| | - Wyatt Madden
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, USA
| | - Alison J Peel
- Centre for Planetary Health and Food Security, Griffith University, Queensland, Australia
| | - Raina K Plowright
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, USA
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4
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Sánchez CA, Penrose MT, Kessler MK, Becker DJ, McKeown A, Hannappel M, Boyd V, Camus MS, Padgett-Stewart T, Hunt BE, Graves AF, Peel AJ, Westcott DA, Rainwater TR, Chumchal MM, Cobb GP, Altizer S, Plowright RK, Boardman WSJ. Land use, season, and parasitism predict metal concentrations in Australian flying fox fur. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 841:156699. [PMID: 35710009 DOI: 10.1016/j.scitotenv.2022.156699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 05/19/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023]
Abstract
Urban-living wildlife can be exposed to metal contaminants dispersed into the environment through industrial, residential, and agricultural applications. Metal exposure carries lethal and sublethal consequences for animals; in particular, heavy metals (e.g. arsenic, lead, mercury) can damage organs and act as carcinogens. Many bat species reside and forage in human-modified habitats and could be exposed to contaminants in air, water, and food. We quantified metal concentrations in fur samples from three flying fox species (Pteropus fruit bats) captured at eight sites in eastern Australia. For subsets of bats, we assessed ectoparasite burden, haemoparasite infection, and viral infection, and performed white blood cell differential counts. We examined relationships among metal concentrations, environmental predictors (season, land use surrounding capture site), and individual predictors (species, sex, age, body condition, parasitism, neutrophil:lymphocyte ratio). As expected, bats captured at sites with greater human impact had higher metal loads. At one site with seasonal sampling, bats had higher metal concentrations in winter than in summer, possibly owing to changes in food availability and foraging. Relationships between ectoparasites and metal concentrations were mixed, suggesting multiple causal mechanisms. There was no association between overall metal load and neutrophil:lymphocyte ratio, but mercury concentrations were positively correlated with this ratio, which is associated with stress in other vertebrate taxa. Comparison of our findings to those of previous flying fox studies revealed potentially harmful levels of several metals; in particular, endangered spectacled flying foxes (P. conspicillatus) exhibited high concentrations of cadmium and lead. Because some bats harbor pathogens transmissible to humans and animals, future research should explore interactions between metal exposure, immunity, and infection to assess consequences for bat and human health.
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Affiliation(s)
- Cecilia A Sánchez
- Odum School of Ecology, University of Georgia, Athens, GA, USA; Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA.
| | - Michael T Penrose
- Department of Environmental Science, Baylor University, Waco, TX, USA
| | | | - Daniel J Becker
- Department of Biology, University of Oklahoma, Norman, OK, USA
| | | | | | - Victoria Boyd
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Health and Biosecurity Business Unit, The Australian Centre for Disease Preparedness (ACDP), Geelong, VIC, Australia
| | - Melinda S Camus
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Ticha Padgett-Stewart
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Brooklin E Hunt
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Amelia F Graves
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Alison J Peel
- Centre for Planetary Health and Food Security, Griffith University, Nathan, QLD, Australia
| | | | - Thomas R Rainwater
- Tom Yawkey Wildlife Center and Belle W. Baruch Institute of Coastal Ecology and Forest Science, Clemson University, Georgetown, SC, USA
| | | | - George P Cobb
- Department of Environmental Science, Baylor University, Waco, TX, USA
| | - Sonia Altizer
- Odum School of Ecology, University of Georgia, Athens, GA, USA; Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
| | - Raina K Plowright
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Wayne S J Boardman
- School of Animal and Veterinary Sciences, University of Adelaide, SA, Australia
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5
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Meade J, Martin JM, Welbergen JA. Fast food in the city? Nomadic flying-foxes commute less and hang around for longer in urban areas. Behav Ecol 2021. [DOI: 10.1093/beheco/arab078] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Abstract
Urbanization creates novel ecological spaces where some species thrive. Geographical urbanization promotes human–wildlife conflict; however, we know relatively little about the drivers of biological urbanization, which poses impediments for sound wildlife management and conservation action. Flying-foxes are extremely mobile and move nomadically in response to flowering resources, but are now increasingly found in urban areas, for reasons that are poorly understood. To investigate the mechanisms behind flying-fox urbanization, we examined the movement of 99 satellite tracked grey-headed flying-foxes (Pteropus poliocephalus) over 1 year in urban versus non-urban environments. We found that tracked individuals preferentially visited major-urban roosts, exhibited higher fidelity to major-urban roosts, and foraged over shorter distances when roosting in major-urban areas. In contrast to other colonial species, there were no density-dependent effects of colony size on foraging distance, suggesting that at a landscape scale, flying-foxes distribute themselves across roosts in an ideal-free manner, minimizing competition over urban and non-urban foraging resources. Yet, males consistently foraged over shorter distances than females, suggesting that at a local scale foraging distances reflect competitive inequalities between individuals. Overall, our study supports the hypothesis that flying-fox urbanization is driven by increased spatiotemporal availability of food resources in urban areas; however, unlike in other species, it is likely a consequence of increased urban visitation by nomadic individuals rather than a subset of the population becoming “urban residents” per se. We discuss the implications of the movement behavior we report for the conservation and management of highly mobile species.
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Affiliation(s)
- Jessica Meade
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Bourke Street, Richmond, NSW, Australia
| | - John M Martin
- Institute of Science and Learning, Taronga Conservation Society Australia, Bradley’s Head Rd, Mosman, 2088 NSW, Australia
| | - Justin A Welbergen
- Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Bourke Street, Richmond, NSW, Australia
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6
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Lunn TJ, Eby P, Brooks R, McCallum H, Plowright RK, Kessler MK, Peel AJ. Conventional wisdom on roosting behavior of Australian flying-foxes-A critical review, and evaluation using new data. Ecol Evol 2021; 11:13532-13558. [PMID: 34646488 PMCID: PMC8495814 DOI: 10.1002/ece3.8079] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 08/14/2021] [Accepted: 08/18/2021] [Indexed: 11/24/2022] Open
Abstract
Fruit bats (Family: Pteropodidae) are animals of great ecological and economic importance, yet their populations are threatened by ongoing habitat loss and human persecution. A lack of ecological knowledge for the vast majority of Pteropodid species presents additional challenges for their conservation and management.In Australia, populations of flying-fox species (Genus: Pteropus) are declining and management approaches are highly contentious. Australian flying-fox roosts are exposed to management regimes involving habitat modification, through human-wildlife conflict management policies, or vegetation restoration programs. Details on the fine-scale roosting ecology of flying-foxes are not sufficiently known to provide evidence-based guidance for these regimes, and the impact on flying-foxes of these habitat modifications is poorly understood.We seek to identify and test commonly held understandings about the roosting ecology of Australian flying-foxes to inform practical recommendations and guide and refine management practices at flying-fox roosts.We identify 31 statements relevant to understanding of flying-fox roosting structure and synthesize these in the context of existing literature. We then contribute a contemporary, fine-scale dataset on within-roost structure to further evaluate 11 of these statements. The new dataset encompasses 13-monthly repeat measures from 2,522 spatially referenced roost trees across eight sites in southeastern Queensland and northeastern New South Wales.We show evidence of sympatry and indirect competition between species, including spatial segregation of black and grey-headed flying-foxes within roosts and seasonal displacement of both species by little red flying-foxes. We demonstrate roost-specific annual trends in occupancy and abundance and provide updated demographic information including the spatial and temporal distributions of males and females within roosts.Insights from our systematic and quantitative study will be important to guide evidence-based recommendations on restoration and management and will be crucial for the implementation of priority recovery actions for the preservation of these species in the future.
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Affiliation(s)
- Tamika J. Lunn
- Centre for Planetary Health and Food SecurityGriffith UniversityNathanQLDAustralia
| | - Peggy Eby
- Centre for Planetary Health and Food SecurityGriffith UniversityNathanQLDAustralia
- School of Biological Earth and Environmental SciencesUniversity of New South WalesSydneyNSWAustralia
| | - Remy Brooks
- Centre for Planetary Health and Food SecurityGriffith UniversityNathanQLDAustralia
| | - Hamish McCallum
- Centre for Planetary Health and Food SecurityGriffith UniversityNathanQLDAustralia
| | - Raina K. Plowright
- Department of Microbiology and ImmunologyMontana State UniversityBozemanMTUSA
| | | | - Alison J. Peel
- Centre for Planetary Health and Food SecurityGriffith UniversityNathanQLDAustralia
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7
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Ranjan R. Mitigating vector-borne pathogen spread risks through promoting Gmelina arborea-based afforestation and agroforestry on private farms. JOURNAL OF CLEANER PRODUCTION 2021; 315:128215. [PMID: 36569227 PMCID: PMC9759379 DOI: 10.1016/j.jclepro.2021.128215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 06/23/2021] [Accepted: 07/02/2021] [Indexed: 06/17/2023]
Abstract
Bat-borne pathogens such as Nipah virus, SARS-CoV2, and Ebola have been causing significant losses to the global economy and human lives. In this paper, the role of afforestation and agroforestry in mitigating risk of bat-borne disease transmission to humans is explored using an epidemiological-agroforestry model of land use decision on private farms. Farmers owning land in fragmented forest areas are financially incentivized to grow Gmelina arborea-based forests or intermix them with agricultural crops. This reduces forest fragmentation through creating connectivity between forest patches. While agroforestry may increase the chances of contact between bats and humans, a reduction in forest fragmentation improves the carrying capacity of bats and reduces their risk of migration and roosting near human dwellings. Results indicate that afforestation on private lands or promoting agroforestry can help reduce the risk of virus transmission to humans. A small sum paid under a payment for ecosystem services (PES) scheme would be sufficient to incentivize farmers to convert their farmlands into Gmelina arborea-based agroforestry or forests. In absence of substantial PES incentives, private landowners may delay land conversion when financial benefits generated through agroforestry timber sales carry higher weight in their optimization decisions. Whereas the socially optimal land use option would be to immediately convert farmland in affected areas to agroforestry or forests. Therefore, from a policy perspective, promoting PES-based forestry and agroforestry in fragmented bat habitats can help prevent spread of deadly viruses in the future.
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Affiliation(s)
- Ram Ranjan
- Department of Economics, School of Humanities and Social Sciences, Shiv Nadar University, Greater Noida, Uttar Pradesh, India
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8
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Lunn TJ, Peel AJ, McCallum H, Eby P, Kessler MK, Plowright RK, Restif O. Spatial dynamics of pathogen transmission in communally roosting species: Impacts of changing habitats on bat-virus dynamics. J Anim Ecol 2021; 90:2609-2622. [PMID: 34192345 PMCID: PMC8441687 DOI: 10.1111/1365-2656.13566] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 06/24/2021] [Indexed: 11/30/2022]
Abstract
The spatial organization of populations determines their pathogen dynamics. This is particularly important for communally roosting species, whose aggregations are often driven by the spatial structure of their environment. We develop a spatially explicit model for virus transmission within roosts of Australian tree‐dwelling bats (Pteropus spp.), parameterized to reflect Hendra virus. The spatial structure of roosts mirrors three study sites, and viral transmission between groups of bats in trees was modelled as a function of distance between roost trees. Using three levels of tree density to reflect anthropogenic changes in bat habitats, we investigate the potential effects of recent ecological shifts in Australia on the dynamics of zoonotic viruses in reservoir hosts. We show that simulated infection dynamics in spatially structured roosts differ from that of mean‐field models for equivalently sized populations, highlighting the importance of spatial structure in disease models of gregarious taxa. Under contrasting scenarios of flying‐fox roosting structures, sparse stand structures (with fewer trees but more bats per tree) generate higher probabilities of successful outbreaks, larger and faster epidemics, and shorter virus extinction times, compared to intermediate and dense stand structures with more trees but fewer bats per tree. These observations are consistent with the greater force of infection generated by structured populations with less numerous but larger infected groups, and may flag an increased risk of pathogen spillover from these increasingly abundant roost types. Outputs from our models contribute insights into the spread of viruses in structured animal populations, like communally roosting species, as well as specific insights into Hendra virus infection dynamics and spillover risk in a situation of changing host ecology. These insights will be relevant for modelling other zoonotic viruses in wildlife reservoir hosts in response to habitat modification and changing populations, including coronaviruses like SARS‐CoV‐2.
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Affiliation(s)
- Tamika J Lunn
- Centre for Planetary Health and Food Security, Griffith University, Brisbane, Qld, Australia.,School of Environment and Science, Griffith University, Brisbane, Qld, Australia
| | - Alison J Peel
- Centre for Planetary Health and Food Security, Griffith University, Brisbane, Qld, Australia
| | - Hamish McCallum
- Centre for Planetary Health and Food Security, Griffith University, Brisbane, Qld, Australia.,School of Environment and Science, Griffith University, Brisbane, Qld, Australia
| | - Peggy Eby
- Centre for Planetary Health and Food Security, Griffith University, Brisbane, Qld, Australia.,School of Biological Earth and Environmental Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Maureen K Kessler
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | | | - Olivier Restif
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
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9
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Mo M, Roache M. A review of intervention methods used to reduce flying-fox mortalities in heat stress events. AUSTRALIAN MAMMALOGY 2021. [DOI: 10.1071/am20038] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Heat stress events in Australian flying-fox camps have resulted in significant numbers of flying-fox deaths. The frequency and intensity of such events have increased in recent decades, attributed to anthropogenic climate change. Evidence-based interventions are required to address this growing threat. Responders currently use different combinations of a range of intervention methods. We undertook a systematic review of heat stress interventions, which we classified as either ‘camp-scale’ or ‘individual-scale’. Camp-scale interventions included manual and automated misting of roost vegetation, whereas individual-scale interventions included spraying individual animals or removing them for intensive cooling and rehydration procedures. Our study showed that to date, evaluation of the efficacy of heat stress interventions has been largely anecdotal rather than empirical. This highlights the need for dedicated rigorous studies to evaluate the effectiveness of all the intervention methods described here. It will be especially important to understand the relationship between camp temperature and humidity levels and their influence on flying-foxes’ ability to regulate their body temperature, because high relative humidity reduces the ability of mammals to cool themselves using evaporative heat loss. The development of biophysiological measures such as temperature and humidity indices for different flying-fox species would enable meaningful interpretations of intervention trials under controlled conditions.
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10
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Welbergen JA, Meade J, Field HE, Edson D, McMichael L, Shoo LP, Praszczalek J, Smith C, Martin JM. Extreme mobility of the world's largest flying mammals creates key challenges for management and conservation. BMC Biol 2020; 18:101. [PMID: 32819385 PMCID: PMC7440933 DOI: 10.1186/s12915-020-00829-w] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 07/13/2020] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Effective conservation management of highly mobile species depends upon detailed knowledge of movements of individuals across their range; yet, data are rarely available at appropriate spatiotemporal scales. Flying-foxes (Pteropus spp.) are large bats that forage by night on floral resources and rest by day in arboreal roosts that may contain colonies of many thousands of individuals. They are the largest mammals capable of powered flight, and are highly mobile, which makes them key seed and pollen dispersers in forest ecosystems. However, their mobility also facilitates transmission of zoonotic diseases and brings them in conflict with humans, and so they require a precarious balancing of conservation and management concerns throughout their Old World range. Here, we analyze the Australia-wide movements of 201 satellite-tracked individuals, providing unprecedented detail on the inter-roost movements of three flying-fox species: Pteropus alecto, P. poliocephalus, and P. scapulatus across jurisdictions over up to 5 years. RESULTS Individuals were estimated to travel long distances annually among a network of 755 roosts (P. alecto, 1427-1887 km; P. poliocephalus, 2268-2564 km; and P. scapulatus, 3782-6073 km), but with little uniformity among their directions of travel. This indicates that flying-fox populations are composed of extremely mobile individuals that move nomadically and at species-specific rates. Individuals of all three species exhibited very low fidelity to roosts locally, resulting in very high estimated daily colony turnover rates (P. alecto, 11.9 ± 1.3%; P. poliocephalus, 17.5 ± 1.3%; and P. scapulatus, 36.4 ± 6.5%). This indicates that flying-fox roosts form nodes in a vast continental network of highly dynamic "staging posts" through which extremely mobile individuals travel far and wide across their species ranges. CONCLUSIONS The extreme inter-roost mobility reported here demonstrates the extent of the ecological linkages that nomadic flying-foxes provide across Australia's contemporary fragmented landscape, with profound implications for the ecosystem services and zoonotic dynamics of flying-fox populations. In addition, the extreme mobility means that impacts from local management actions can readily reverberate across jurisdictions throughout the species ranges; therefore, local management actions need to be assessed with reference to actions elsewhere and hence require national coordination. These findings underscore the need for sound understanding of animal movement dynamics to support evidence-based, transboundary conservation and management policy, tailored to the unique movement ecologies of species.
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Affiliation(s)
- Justin A Welbergen
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, 2753, Australia.
| | - Jessica Meade
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, 2753, Australia
| | - Hume E Field
- Department of Agriculture and Fisheries, Queensland Centre for Emerging Infectious Diseases, Brisbane, QLD, 4001, Australia
- Ecohealth Alliance, New York, NY, 10001, USA
- School of Veterinary Science, The University of Queensland, Gatton, QLD, 4343, Australia
| | - Daniel Edson
- Department of Agriculture and Fisheries, Queensland Centre for Emerging Infectious Diseases, Brisbane, QLD, 4001, Australia
- Department of Agriculture, Water and the Environment, Canberra, ACT, 2601, Australia
| | - Lee McMichael
- Department of Agriculture and Fisheries, Queensland Centre for Emerging Infectious Diseases, Brisbane, QLD, 4001, Australia
- School of Veterinary Science, The University of Queensland, Gatton, QLD, 4343, Australia
| | - Luke P Shoo
- School of Biological Sciences, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Jenny Praszczalek
- Royal Botanic Gardens and Domain Trust, Sydney, NSW, 2000, Australia
| | - Craig Smith
- Department of Agriculture and Fisheries, Queensland Centre for Emerging Infectious Diseases, Brisbane, QLD, 4001, Australia
| | - John M Martin
- Royal Botanic Gardens and Domain Trust, Sydney, NSW, 2000, Australia
- Institute for Science and Learning, Taronga Conservation Society Australia, Mosman, NSW, 2088, Australia
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11
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Seroprevalence of three paramyxoviruses; Hendra virus, Tioman virus, Cedar virus and a rhabdovirus, Australian bat lyssavirus, in a range expanding fruit bat, the Grey-headed flying fox (Pteropus poliocephalus). PLoS One 2020; 15:e0232339. [PMID: 32374743 PMCID: PMC7202650 DOI: 10.1371/journal.pone.0232339] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 04/13/2020] [Indexed: 12/23/2022] Open
Abstract
Habitat-mediated global change is driving shifts in species’ distributions which can alter the spatial risks associated with emerging zoonotic pathogens. Many emerging infectious pathogens are transmitted by highly mobile species, including bats, which can act as spill-over hosts for pathogenic viruses. Over three years, we investigated the seroepidemiology of paramyxoviruses and Australian bat lyssavirus in a range-expanding fruit bat, the Grey-headed flying fox (Pteropus poliocephalus), in a new camp in Adelaide, South Australia. Over six, biannual, sampling sessions, we quantified median florescent intensity (MFI) antibody levels for four viruses for a total of 297 individual bats using a multiplex Luminex binding assay. Where appropriate, florescence thresholds were determined using finite mixture modelling to classify bats’ serological status. Overall, apparent seroprevalence of antibodies directed at Hendra, Cedar and Tioman virus antigens was 43.2%, 26.6% and 95.7%, respectively. We used hurdle models to explore correlates of seropositivity and antibody levels when seropositive. Increased body condition was significantly associated with Hendra seropositivity (Odds ratio = 3.67; p = 0.002) and Hendra virus levels were significantly higher in pregnant females (p = 0.002). While most bats were seropositive for Tioman virus, antibody levels for this virus were significantly higher in adults (p < 0.001). Unexpectedly, all sera were negative for Australian bat lyssavirus. Temporal variation in antibody levels suggests that antibodies to Hendra virus and Tioman virus may wax and wane on a seasonal basis. These findings suggest a common exposure to Hendra virus and other paramyxoviruses in this flying fox camp in South Australia.
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12
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Schlägel UE, Grimm V, Blaum N, Colangeli P, Dammhahn M, Eccard JA, Hausmann SL, Herde A, Hofer H, Joshi J, Kramer-Schadt S, Litwin M, Lozada-Gobilard SD, Müller MEH, Müller T, Nathan R, Petermann JS, Pirhofer-Walzl K, Radchuk V, Rillig MC, Roeleke M, Schäfer M, Scherer C, Schiro G, Scholz C, Teckentrup L, Tiedemann R, Ullmann W, Voigt CC, Weithoff G, Jeltsch F. Movement-mediated community assembly and coexistence. Biol Rev Camb Philos Soc 2020; 95:1073-1096. [PMID: 32627362 DOI: 10.1111/brv.12600] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 03/20/2020] [Accepted: 03/23/2020] [Indexed: 01/11/2023]
Abstract
Organismal movement is ubiquitous and facilitates important ecological mechanisms that drive community and metacommunity composition and hence biodiversity. In most existing ecological theories and models in biodiversity research, movement is represented simplistically, ignoring the behavioural basis of movement and consequently the variation in behaviour at species and individual levels. However, as human endeavours modify climate and land use, the behavioural processes of organisms in response to these changes, including movement, become critical to understanding the resulting biodiversity loss. Here, we draw together research from different subdisciplines in ecology to understand the impact of individual-level movement processes on community-level patterns in species composition and coexistence. We join the movement ecology framework with the key concepts from metacommunity theory, community assembly and modern coexistence theory using the idea of micro-macro links, where various aspects of emergent movement behaviour scale up to local and regional patterns in species mobility and mobile-link-generated patterns in abiotic and biotic environmental conditions. These in turn influence both individual movement and, at ecological timescales, mechanisms such as dispersal limitation, environmental filtering, and niche partitioning. We conclude by highlighting challenges to and promising future avenues for data generation, data analysis and complementary modelling approaches and provide a brief outlook on how a new behaviour-based view on movement becomes important in understanding the responses of communities under ongoing environmental change.
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Affiliation(s)
- Ulrike E Schlägel
- Plant Ecology and Nature Conservation, University of Potsdam, Am Mühlenberg 3, 14476, Potsdam, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany
| | - Volker Grimm
- Plant Ecology and Nature Conservation, University of Potsdam, Am Mühlenberg 3, 14476, Potsdam, Germany.,Department of Ecological Modelling, Helmholtz Centre for Environmental Research-UFZ, Permoserstr. 15, 04318, Leipzig, Germany.,German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103, Leipzig, Germany
| | - Niels Blaum
- Plant Ecology and Nature Conservation, University of Potsdam, Am Mühlenberg 3, 14476, Potsdam, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany
| | - Pierluigi Colangeli
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Department of Ecology and Ecosystem Modelling, University of Potsdam, Maulbeerallee 2, 14469, Potsdam, Germany
| | - Melanie Dammhahn
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Animal Ecology, University of Potsdam, Maulbeerallee 1, 14469, Potsdam, Germany
| | - Jana A Eccard
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Animal Ecology, University of Potsdam, Maulbeerallee 1, 14469, Potsdam, Germany
| | - Sebastian L Hausmann
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Plant Ecology, Institute of Biology, Freie Universität Berlin, 14195, Berlin, Germany
| | - Antje Herde
- Plant Ecology and Nature Conservation, University of Potsdam, Am Mühlenberg 3, 14476, Potsdam, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Department of Animal Behaviour, Bielefeld University, Morgenbreede 45, 33615, Bielefeld, Germany
| | - Heribert Hofer
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany.,Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany.,Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, Berlin, Germany
| | - Jasmin Joshi
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Biodiversity Research and Systematic Botany, University of Potsdam, Maulbeerallee 2, 14469, Potsdam, Germany.,Institute for Landscape and Open Space, Hochschule für Technik HSR Rapperswil, Seestrasse 10, 8640 Rapperswil, Switzerland
| | - Stephanie Kramer-Schadt
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany.,Department of Ecology, Technische Universität Berlin, Rothenburgstr. 12, 12165, Berlin, Germany
| | - Magdalena Litwin
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Evolutionary Biology/Systematic Zoology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany
| | - Sissi D Lozada-Gobilard
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Biodiversity Research and Systematic Botany, University of Potsdam, Maulbeerallee 2, 14469, Potsdam, Germany
| | - Marina E H Müller
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz-Centre for Agricultural Landscape Research (ZALF), Eberswalder Str. 84, 15374, Müncheberg, Germany
| | - Thomas Müller
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz-Centre for Agricultural Landscape Research (ZALF), Eberswalder Str. 84, 15374, Müncheberg, Germany
| | - Ran Nathan
- Department of Ecology, Evolution and Behavior, Movement Ecology Laboratory, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Jana S Petermann
- Department of Biosciences, University of Salzburg, Hellbrunner Straße 34, 5020, Salzburg, Austria
| | - Karin Pirhofer-Walzl
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Plant Ecology, Institute of Biology, Freie Universität Berlin, 14195, Berlin, Germany.,Leibniz-Centre for Agricultural Landscape Research (ZALF), Eberswalder Str. 84, 15374, Müncheberg, Germany
| | - Viktoriia Radchuk
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany
| | - Matthias C Rillig
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Plant Ecology, Institute of Biology, Freie Universität Berlin, 14195, Berlin, Germany
| | - Manuel Roeleke
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany
| | - Merlin Schäfer
- Plant Ecology and Nature Conservation, University of Potsdam, Am Mühlenberg 3, 14476, Potsdam, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz-Centre for Agricultural Landscape Research (ZALF), Eberswalder Str. 84, 15374, Müncheberg, Germany
| | - Cédric Scherer
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany
| | - Gabriele Schiro
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz-Centre for Agricultural Landscape Research (ZALF), Eberswalder Str. 84, 15374, Müncheberg, Germany
| | - Carolin Scholz
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany
| | - Lisa Teckentrup
- Plant Ecology and Nature Conservation, University of Potsdam, Am Mühlenberg 3, 14476, Potsdam, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany
| | - Ralph Tiedemann
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Evolutionary Biology/Systematic Zoology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany
| | - Wiebke Ullmann
- Plant Ecology and Nature Conservation, University of Potsdam, Am Mühlenberg 3, 14476, Potsdam, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz-Centre for Agricultural Landscape Research (ZALF), Eberswalder Str. 84, 15374, Müncheberg, Germany
| | - Christian C Voigt
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany.,Behavioral Biology, Institute of Biology, Freie Universität Berlin, Takustr. 6, 14195, Berlin, Germany
| | - Guntram Weithoff
- Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany.,Department of Ecology and Ecosystem Modelling, University of Potsdam, Maulbeerallee 2, 14469, Potsdam, Germany
| | - Florian Jeltsch
- Plant Ecology and Nature Conservation, University of Potsdam, Am Mühlenberg 3, 14476, Potsdam, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), Altensteinstr. 34, 14195, Berlin, Germany
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13
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Griffith P, Parry-Jones K, Cunningham AA. Dietary partitioning in newly sympatric urban flying-foxes (Pteropus poliocephalus and Pteropus alecto). AUSTRALIAN MAMMALOGY 2020. [DOI: 10.1071/am19047] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The black flying-fox (Pteropus alecto) is extending its range southward and is now sympatric with the grey-headed flying-fox (P. poliocephalus) in New South Wales. Competition for food between the two species has been suggested to be a contributor to declines of the vulnerable grey-headed flying-fox. During winter 2016 the diet of both species was investigated over one night at four sites of sympatry, by microscopic analysis of faecal samples. Resource partitioning between the two species was found, with the black flying-fox either preferentially choosing to eat more fruit than the grey-headed flying-fox or being an inferior competitor for pollen and nectar. These results, though limited, do not support the hypothesis that the black flying-fox threatens the grey-headed flying-fox through food competition.
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14
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Roberts BJ, Mo M, Roache M, Eby P. Review of dispersal attempts at flying-fox camps in Australia. AUST J ZOOL 2020. [DOI: 10.1071/zo20043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The permanent exclusion of flying-foxes from camps (camp dispersal) near human settlements is a management tool commonly used to mitigate human–wildlife conflict. We summarised information on the costs and outcomes of 48 camp dispersals in Australia. Our aim was to improve the information base on which camp management decisions are made. Camp dispersals were largely triggered by impacts on neighbouring residents (75%). A disproportionately high number occurred in 2013–14, associated with changes in Queensland flying-fox management policy following an increase in the number of urban camps. Repeat actions over months or years were typically required to exclude flying-foxes from camps (58%). In 88% of cases, replacement camps formed within 1 km and became sites of transferred conflict. Only 23% of dispersal attempts were successful in resolving conflict for communities, generally after extensive destruction of roost habitat. Costs were poorly documented, although no dispersal attempt costing less than AU$250 000 proved successful. We conclude that camp dispersal is a high-risk, high-cost tool for mitigating human–wildlife conflict, in situ management strategies and tools should be developed, evidence-based information on management options should be made available to stakeholders via a nationally curated resource library, and research is required on impacts of camp management practices on flying-foxes.
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15
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Oedin M, Brescia F, Boissenin M, Vidal E, Cassan JJ, Hurlin JC, Millon A. Monitoring hunted species of cultural significance: Estimates of trends, population sizes and harvesting rates of flying-fox (Pteropus sp.) in New Caledonia. PLoS One 2019; 14:e0224466. [PMID: 31891573 PMCID: PMC6938311 DOI: 10.1371/journal.pone.0224466] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 10/14/2019] [Indexed: 11/18/2022] Open
Abstract
Assessing population trends and their underlying factors is critical to propose efficient conservation actions. This assessment can be particularly challenging when dealing with highly mobile, shy and nocturnal animals such as flying-foxes. Here we investigated the dynamics of hunted populations of Pteropus ornatus and P. tonganus in the Northern Province of New Caledonia. First, an ethno-ecological survey involving 219 local experts identified 494 flying-fox roosts. Current status was assessed for 379 of them, among which 125 were no longer occupied, representing a loss of 33% over ca. 40 years. Second, species-specific counts conducted at 35 roosts, and a sample of animals killed by hunters, revealed that the endemic species, P. ornatus, was dominant (68.5%). Between 2010 and 2016, 30 roosts were counted annually during the pre-parturition period. Roosts size averaged 1,425 ± 2,151 individuals (N = 180 counts) and showed high among-year variations (roost-specific CV = 37-162%). If we recorded significant inter-annual variation, we did not detect a significant decline over the 7-yr period, although one roost went possibly extinct. Population size of the two species combined was estimated at 338,000-859,000 individuals distributed over ca. 400 roosts in the Northern Province. Flying-foxes are popular game species and constitute traditional food for all communities of New Caledonia. Annual bags derived from a food survey allowed us to estimate harvesting rates at 5-14%. Such a level of harvesting for species with a 'slow' demography, the occurrence of poaching and illegal trade, suggest the current species use might not be sustainable and further investigations are critically needed.
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Affiliation(s)
- Malik Oedin
- Institut Agronomique Néo-Calédonien (IAC), Equipe ARBOREAL (AgricultuRe BiOdiveRsité Et vALorisation) BP, Païta, Nouvelle-Calédonie
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Aix Marseille Université, CNRS, IRD, Avignon Université, Centre IRD Nouméa, Nouvelle-Calédonie
| | - Fabrice Brescia
- Institut Agronomique Néo-Calédonien (IAC), Equipe ARBOREAL (AgricultuRe BiOdiveRsité Et vALorisation) BP, Païta, Nouvelle-Calédonie
| | - Mélanie Boissenin
- Institut Agronomique Néo-Calédonien (IAC), Equipe ARBOREAL (AgricultuRe BiOdiveRsité Et vALorisation) BP, Païta, Nouvelle-Calédonie
| | - Eric Vidal
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Aix Marseille Université, CNRS, IRD, Avignon Université, Centre IRD Nouméa, Nouvelle-Calédonie
- UMR Entropie (IRD, Université de La Réunion, CNRS), Labex-Corail, Institut de Recherche pour le Développement (IRD), Nouvelle-Calédonie
| | - Jean-Jérôme Cassan
- Province Nord, Direction du Développement Economique et de l’Environnement, Service impact environnemental et conservation (DDEE), Service impact environnemental & conservation, Koné, Nouvelle-Calédonie
| | - Jean-Claude Hurlin
- Institut Agronomique Néo-Calédonien (IAC), Equipe ARBOREAL (AgricultuRe BiOdiveRsité Et vALorisation) BP, Païta, Nouvelle-Calédonie
| | - Alexandre Millon
- Aix Marseille Université, CNRS, IRD, Avignon Université, Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Technopôle Arbois-Méditerranée, Aix-en-Provence, France
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16
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Becker DJ, Washburne AD, Faust CL, Mordecai EA, Plowright RK. The problem of scale in the prediction and management of pathogen spillover. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190224. [PMID: 31401958 PMCID: PMC6711304 DOI: 10.1098/rstb.2019.0224] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2019] [Indexed: 01/28/2023] Open
Abstract
Disease emergence events, epidemics and pandemics all underscore the need to predict zoonotic pathogen spillover. Because cross-species transmission is inherently hierarchical, involving processes that occur at varying levels of biological organization, such predictive efforts can be complicated by the many scales and vastness of data potentially required for forecasting. A wide range of approaches are currently used to forecast spillover risk (e.g. macroecology, pathogen discovery, surveillance of human populations, among others), each of which is bound within particular phylogenetic, spatial and temporal scales of prediction. Here, we contextualize these diverse approaches within their forecasting goals and resulting scales of prediction to illustrate critical areas of conceptual and pragmatic overlap. Specifically, we focus on an ecological perspective to envision a research pipeline that connects these different scales of data and predictions from the aims of discovery to intervention. Pathogen discovery and predictions focused at the phylogenetic scale can first provide coarse and pattern-based guidance for which reservoirs, vectors and pathogens are likely to be involved in spillover, thereby narrowing surveillance targets and where such efforts should be conducted. Next, these predictions can be followed with ecologically driven spatio-temporal studies of reservoirs and vectors to quantify spatio-temporal fluctuations in infection and to mechanistically understand how pathogens circulate and are transmitted to humans. This approach can also help identify general regions and periods for which spillover is most likely. We illustrate this point by highlighting several case studies where long-term, ecologically focused studies (e.g. Lyme disease in the northeast USA, Hendra virus in eastern Australia, Plasmodium knowlesi in Southeast Asia) have facilitated predicting spillover in space and time and facilitated the design of possible intervention strategies. Such studies can in turn help narrow human surveillance efforts and help refine and improve future large-scale, phylogenetic predictions. We conclude by discussing how greater integration and exchange between data and predictions generated across these varying scales could ultimately help generate more actionable forecasts and interventions. This article is part of the theme issue 'Dynamic and integrative approaches to understanding pathogen spillover'.
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Affiliation(s)
- Daniel J. Becker
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
- Department of Biology, Indiana University, Bloomington, IN, USA
| | - Alex D. Washburne
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Christina L. Faust
- Institute of Biodiversity Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | | | - Raina K. Plowright
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
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17
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Teitelbaum CS, Mueller T. Beyond Migration: Causes and Consequences of Nomadic Animal Movements. Trends Ecol Evol 2019; 34:569-581. [PMID: 30885413 DOI: 10.1016/j.tree.2019.02.005] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 02/08/2019] [Accepted: 02/12/2019] [Indexed: 11/18/2022]
Abstract
Recent advances in animal tracking reveal that many species display irregular movements that do not fall into classical categories of movement patterns such as range residency or migration. Here, we develop a unifying framework that distinguishes these nomadic movements based on their patterns, drivers, and mechanisms. Though they occur in diverse taxa and geographic regions, nomadic movements are united by both their underlying environmental drivers, mainly environmental stochasticity, and the resulting irregular, far-ranging movement patterns. The framework further classifies types of nomadic movements, including full, seasonal, phase, irruptive, and partial nomadism. Nomadic movements can have unique effects on populations, communities, and ecosystems, most notably providing intermittent disturbances and novel introductions of propagules.
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Affiliation(s)
- Claire S Teitelbaum
- Odum School of Ecology, University of Georgia, 140 E Green St., Athens, GA 30602, USA. https://twitter.com/@cs_teitelbaum
| | - Thomas Mueller
- Department of Biological Sciences, Goethe-University Frankfurt and Senckenberg Biodiversity and Climate Research Centre (SBiK-F), Senckenberganlage 25, 60325 Frankfurt, Germany. https://twitter.com/@secnkenberg
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18
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Martin G, Yanez-Arenas C, Chen C, Plowright RK, Webb RJ, Skerratt LF. Climate Change Could Increase the Geographic Extent of Hendra Virus Spillover Risk. ECOHEALTH 2018; 15:509-525. [PMID: 29556762 PMCID: PMC6245089 DOI: 10.1007/s10393-018-1322-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 12/10/2017] [Accepted: 01/29/2018] [Indexed: 05/29/2023]
Abstract
Disease risk mapping is important for predicting and mitigating impacts of bat-borne viruses, including Hendra virus (Paramyxoviridae:Henipavirus), that can spillover to domestic animals and thence to humans. We produced two models to estimate areas at potential risk of HeV spillover explained by the climatic suitability for its flying fox reservoir hosts, Pteropus alecto and P. conspicillatus. We included additional climatic variables that might affect spillover risk through other biological processes (such as bat or horse behaviour, plant phenology and bat foraging habitat). Models were fit with a Poisson point process model and a log-Gaussian Cox process. In response to climate change, risk expanded southwards due to an expansion of P. alecto suitable habitat, which increased the number of horses at risk by 175-260% (110,000-165,000). In the northern limits of the current distribution, spillover risk was highly uncertain because of model extrapolation to novel climatic conditions. The extent of areas at risk of spillover from P. conspicillatus was predicted shrink. Due to a likely expansion of P. alecto into these areas, it could replace P. conspicillatus as the main HeV reservoir. We recommend: (1) HeV monitoring in bats, (2) enhancing HeV prevention in horses in areas predicted to be at risk, (3) investigate and develop mitigation strategies for areas that could experience reservoir host replacements.
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Affiliation(s)
- Gerardo Martin
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia.
- , Guadalupe Victoria, Mexico.
- Ecological Health Research Group, Department of Infectious Disease Epidemiology, Imperial College London, St. Mary's campus, Praed Street, London, W2 1NY, UK.
| | - Carlos Yanez-Arenas
- Laboratorio de Conservación de la Biodiversidad, Parque Científico y Tecnológico de Yucatán, Universidad, Universidad Nacional Autónoma de México, Mérida, Yucatán, Mexico
| | - Carla Chen
- Australian Institute of Marine Sciences, Townsville, QLD, Australia
| | - Raina K Plowright
- Bozeman Disease Ecology Lab, Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Rebecca J Webb
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia
| | - Lee F Skerratt
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia
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19
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Kessler MK, Becker DJ, Peel AJ, Justice NV, Lunn T, Crowley DE, Jones DN, Eby P, Sánchez CA, Plowright RK. Changing resource landscapes and spillover of henipaviruses. Ann N Y Acad Sci 2018; 1429:78-99. [PMID: 30138535 DOI: 10.1111/nyas.13910] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 05/11/2018] [Accepted: 05/29/2018] [Indexed: 12/14/2022]
Abstract
Old World fruit bats (Chiroptera: Pteropodidae) provide critical pollination and seed dispersal services to forest ecosystems across Africa, Asia, and Australia. In each of these regions, pteropodids have been identified as natural reservoir hosts for henipaviruses. The genus Henipavirus includes Hendra virus and Nipah virus, which regularly spill over from bats to domestic animals and humans in Australia and Asia, and a suite of largely uncharacterized African henipaviruses. Rapid change in fruit bat habitat and associated shifts in their ecology and behavior are well documented, with evidence suggesting that altered diet, roosting habitat, and movement behaviors are increasing spillover risk of bat-borne viruses. We review the ways that changing resource landscapes affect the processes that culminate in cross-species transmission of henipaviruses, from reservoir host density and distribution to within-host immunity and recipient host exposure. We evaluate existing evidence and highlight gaps in knowledge that are limiting our understanding of the ecological drivers of henipavirus spillover. When considering spillover in the context of land-use change, we emphasize that it is especially important to disentangle the effects of habitat loss and resource provisioning on these processes, and to jointly consider changes in resource abundance, quality, and composition.
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Affiliation(s)
| | - Daniel J Becker
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana.,The Center for the Ecology of Infectious Diseases, University of Georgia, Athens, Georgia
| | - Alison J Peel
- Environmental Futures Research Institute, Griffith University, Nathan, Queensland, Australia
| | - Nathan V Justice
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | - Tamika Lunn
- The Griffith School of Environment, Griffith University, Nathan, Queensland, Australia
| | - Daniel E Crowley
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | - Devin N Jones
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | - Peggy Eby
- The School of Biological, Earth, and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Cecilia A Sánchez
- The Center for the Ecology of Infectious Diseases, University of Georgia, Athens, Georgia.,The Odum School of Ecology, University of Georgia, Athens, Georgia
| | - Raina K Plowright
- Department of Ecology, Montana State University, Bozeman, Montana.,Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
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20
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Giles JR, Eby P, Parry H, Peel AJ, Plowright RK, Westcott DA, McCallum H. Environmental drivers of spatiotemporal foraging intensity in fruit bats and implications for Hendra virus ecology. Sci Rep 2018; 8:9555. [PMID: 29934514 PMCID: PMC6015053 DOI: 10.1038/s41598-018-27859-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 05/23/2018] [Indexed: 12/13/2022] Open
Abstract
In the Australian subtropics, flying-foxes (family Pteropididae) play a fundamental ecological role as forest pollinators. Flying-foxes are also reservoirs of the fatal zoonosis, Hendra virus. Understanding flying fox foraging ecology, particularly in agricultural areas during winter, is critical to determine their role in transmitting Hendra virus to horses and humans. We developed a spatiotemporal model of flying-fox foraging intensity based on foraging patterns of 37 grey-headed flying-foxes (Pteropus poliocephalus) using GPS tracking devices and boosted regression trees. We validated the model with independent population counts and summarized temporal patterns in terms of spatial resource concentration. We found that spatial resource concentration was highest in late-summer and lowest in winter, with lowest values in winter 2011, the same year an unprecedented cluster of spillover events occurred in Queensland and New South Wales. Spatial resource concentration was positively correlated with El Niño Southern Oscillation at 3–8 month time lags. Based on shared foraging traits with the primary reservoir of Hendra virus (Pteropus alecto), we used our results to develop hypotheses on how regional climatic history, eucalypt phenology, and foraging behaviour may contribute to the predominance of winter spillovers, and how these phenomena connote foraging habitat conservation as a public health intervention.
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Affiliation(s)
- John R Giles
- Johns Hopkins University Bloomberg School of Public Health, Department of Epidemiology, Baltimore, MD, USA. .,Environmental Futures Research Institute, Griffith University, Brisbane, QLD, Australia.
| | - Peggy Eby
- School of Biological, Earth, and Environmental Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Hazel Parry
- CSIRO Health and Biosecurity, Brisbane, Queensland, 4001, Australia
| | - Alison J Peel
- Johns Hopkins University Bloomberg School of Public Health, Department of Epidemiology, Baltimore, MD, USA
| | - Raina K Plowright
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | | | - Hamish McCallum
- Johns Hopkins University Bloomberg School of Public Health, Department of Epidemiology, Baltimore, MD, USA
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Land Manager Perspectives on Conflict Mitigation Strategies for Urban Flying-Fox Camps. DIVERSITY 2018. [DOI: 10.3390/d10020039] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Conditions affecting the timing and magnitude of Hendra virus shedding across pteropodid bat populations in Australia. Epidemiol Infect 2017; 145:3143-3153. [PMID: 28942750 DOI: 10.1017/s0950268817002138] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Understanding infection dynamics in animal hosts is fundamental to managing spillover and emergence of zoonotic infections. Hendra virus is endemic in Australian pteropodid bat populations and can be lethal to horses and humans. However, we know little about the factors driving Hendra virus prevalence in resevoir bat populations, making spillover difficult to predict. We use Hendra virus prevalence data collected from 13 000 pooled bat urine samples across space and time to determine if pulses of prevalence are periodic and synchronized across sites. We also test whether site-specific precipitation and temperature affect the amplitude of the largest annual prevalence pulses. We found little evidence for a periodic signal in Hendra virus prevalence. Although the largest amplitude pulses tended to occur over winter, pulses could also occur in other seasons. We found that Hendra virus prevalence was weakly synchronized across sites over short distances, suggesting that prevalence is driven by local-scale effects. Finally, we found that drier conditions in previous seasons and the abundance of Pteropus alecto were positively correlated with the peak annual values of Hendra virus prevalence. Our results suggest that in addition to seasonal effects, bat density and local climatic conditions interact to drive Hendra virus infection dynamics.
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Peel AJ, Wood JLN, Baker KS, Breed AC, Carvalho AD, Fernández-Loras A, Gabrieli HS, Gembu GC, Kakengi VA, Kaliba PM, Kityo RM, Lembo T, Mba FE, Ramos D, Rodriguez-Prieto I, Suu-Ire R, Cunningham AA, Hayman DTS. How Does Africa's Most Hunted Bat Vary Across the Continent? Population Traits of the Straw-Coloured Fruit Bat (Eidolon helvum) and Its Interactions with Humans. ACTA CHIROPTEROLOGICA 2017. [DOI: 10.3161/15081109acc2017.19.1.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Alison J. Peel
- Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, United Kingdom
| | - James L. N. Wood
- Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, United Kingdom
| | - Kate S. Baker
- Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, United Kingdom
| | - Andrew C. Breed
- Animal and Plant Health Agency (APHA), Addlestone, Surrey, KT15 3NB, United Kingdom
| | - Arlindo De Carvalho
- Direção Geral de Ambiente, Avenida Kwame Krhuma-Caixa Postal 1023, São Tomé, São Tomé e Príncipe
| | - Andrés Fernández-Loras
- Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, United Kingdom
| | - Harrison Sadiki Gabrieli
- Tanzania Veterinary Laboratory Agency (TVLA), Ministry of Livestock Development and Fisheries (MLDF), P.O. Box 1026, Tanga, Tanzania
| | - Guy-Crispin Gembu
- Faculté des Sciences, Université de Kisangani, Kisangani, République Démocratique du Congo
| | | | | | - Robert M. Kityo
- College of Natural Sciences, School of BioSciences, Department of Biological Sciences. Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Tiziana Lembo
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Graham Kerr Building, Glasgow, G12 8QQ, Scotland
| | - Fidel Esono Mba
- Instituto Nacional de Desarrollo Forestal y Manejo del Sistema de Áreas Protegidas (INDEFOR-AP), Calle Jesús Bakale S/N, Bata, Equatorial Guinea
| | - Daniel Ramos
- Parque Natural do Príncipe, Avenida Amilcar Cabral, Cidade de Santo António, Ilha do Príncipe, São Tomé e Príncipe
| | - Iñaki Rodriguez-Prieto
- Department of Evolutionary Ecology, Museo Nacional de Ciencias Naturales, CSIC 28006 Madrid, Spain
| | | | - Andrew A. Cunningham
- Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, United Kingdom
| | - David T. S. Hayman
- Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, United Kingdom
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Giles JR, Plowright RK, Eby P, Peel AJ, McCallum H. Models of Eucalypt phenology predict bat population flux. Ecol Evol 2016; 6:7230-7245. [PMID: 27891217 PMCID: PMC5115174 DOI: 10.1002/ece3.2382] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 07/21/2016] [Indexed: 12/11/2022] Open
Abstract
Fruit bats (Pteropodidae) have received increased attention after the recent emergence of notable viral pathogens of bat origin. Their vagility hinders data collection on abundance and distribution, which constrains modeling efforts and our understanding of bat ecology, viral dynamics, and spillover. We addressed this knowledge gap with models and data on the occurrence and abundance of nectarivorous fruit bat populations at 3 day roosts in southeast Queensland. We used environmental drivers of nectar production as predictors and explored relationships between bat abundance and virus spillover. Specifically, we developed several novel modeling tools motivated by complexities of fruit bat foraging ecology, including: (1) a dataset of spatial variables comprising Eucalypt-focused vegetation indices, cumulative precipitation, and temperature anomaly; (2) an algorithm that associated bat population response with spatial covariates in a spatially and temporally relevant way given our current understanding of bat foraging behavior; and (3) a thorough statistical learning approach to finding optimal covariate combinations. We identified covariates that classify fruit bat occupancy at each of our three study roosts with 86-93% accuracy. Negative binomial models explained 43-53% of the variation in observed abundance across roosts. Our models suggest that spatiotemporal heterogeneity in Eucalypt-based food resources could drive at least 50% of bat population behavior at the landscape scale. We found that 13 spillover events were observed within the foraging range of our study roosts, and they occurred during times when models predicted low population abundance. Our results suggest that, in southeast Queensland, spillover may not be driven by large aggregations of fruit bats attracted by nectar-based resources, but rather by behavior of smaller resident subpopulations. Our models and data integrated remote sensing and statistical learning to make inferences on bat ecology and disease dynamics. This work provides a foundation for further studies on landscape-scale population movement and spatiotemporal disease dynamics.
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Affiliation(s)
- John R. Giles
- Environmental Futures Research InstituteGriffith UniversityBrisbaneQueensland4111Australia
| | - Raina K. Plowright
- Department of Microbiology and ImmunologyMontana State UniversityBozemanMontana59717
| | - Peggy Eby
- School of Biological, Earth, and Environmental SciencesUniversity of New South WalesSydneyNew South Wales2052Australia
| | - Alison J. Peel
- Environmental Futures Research InstituteGriffith UniversityBrisbaneQueensland4111Australia
| | - Hamish McCallum
- Environmental Futures Research InstituteGriffith UniversityBrisbaneQueensland4111Australia
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Abstract
Little is known about the ecology of many of the parasites and pathogens affecting bats, but host social behavior almost certainly plays an important role in bat-parasite dynamics. Understanding parasite dynamics for bats is important from a human public health perspective because of their role as natural reservoirs for recent high-profile emerging zoonotic pathogens (e.g. Ebola, Hendra) and from a bat conservation perspective because of the recent emergence of white-nose syndrome (WNS) in North America highlighting the potential population impacts of parasites and pathogens. Although some bat species are among the most gregarious of mammals, species vary widely in terms of their social behavior and this variation could influence pathogen transmission and impacts. Here, we review the literature on links between bat social behavior and parasite dynamics. Using standardized search terms in Web of Science, we identified articles that explicitly tested or discussed links between some aspect of bat sociality and parasite transmission or host population impacts. We identified social network analysis, epidemiological modeling, and interspecific comparative analyses as the most commonly used methods to quantify relationships between social behavior and parasite-risk in bats while WNS, Hendra virus, and arthropod ectoparasites were the most commonly studied host-parasite systems. We summarize known host-parasite relationships in these three systems and propose testable hypotheses that could improve our understanding of links between host sociality and parasite-dynamics in bats.
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Affiliation(s)
- Jorge Ortega
- Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México City, Mexico
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Plowright RK, Eby P, Hudson PJ, Smith IL, Westcott D, Bryden WL, Middleton D, Reid PA, McFarlane RA, Martin G, Tabor GM, Skerratt LF, Anderson DL, Crameri G, Quammen D, Jordan D, Freeman P, Wang LF, Epstein JH, Marsh GA, Kung NY, McCallum H. Ecological dynamics of emerging bat virus spillover. Proc Biol Sci 2015; 282:20142124. [PMID: 25392474 DOI: 10.1098/rspb.2014.2124] [Citation(s) in RCA: 298] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Viruses that originate in bats may be the most notorious emerging zoonoses that spill over from wildlife into domestic animals and humans. Understanding how these infections filter through ecological systems to cause disease in humans is of profound importance to public health. Transmission of viruses from bats to humans requires a hierarchy of enabling conditions that connect the distribution of reservoir hosts, viral infection within these hosts, and exposure and susceptibility of recipient hosts. For many emerging bat viruses, spillover also requires viral shedding from bats, and survival of the virus in the environment. Focusing on Hendra virus, but also addressing Nipah virus, Ebola virus, Marburg virus and coronaviruses, we delineate this cross-species spillover dynamic from the within-host processes that drive virus excretion to land-use changes that increase interaction among species. We describe how land-use changes may affect co-occurrence and contact between bats and recipient hosts. Two hypotheses may explain temporal and spatial pulses of virus shedding in bat populations: episodic shedding from persistently infected bats or transient epidemics that occur as virus is transmitted among bat populations. Management of livestock also may affect the probability of exposure and disease. Interventions to decrease the probability of virus spillover can be implemented at multiple levels from targeting the reservoir host to managing recipient host exposure and susceptibility.
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Affiliation(s)
- Raina K Plowright
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT 59717, USA Center for Infectious Disease Dynamics, Pennsylvania State University, State College, PA, USA
| | - Peggy Eby
- School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Peter J Hudson
- Center for Infectious Disease Dynamics, Pennsylvania State University, State College, PA, USA
| | - Ina L Smith
- New and Emerging Zoonotic Diseases, CSIRO, Australian Animal Health Laboratory, East Geelong, Victoria 3220, Australia
| | - David Westcott
- CSIRO Ecosystem Sciences and Tropical Environment and Sustainability Sciences, James Cook University, Atherton, Queensland 4883, Australia
| | - Wayne L Bryden
- Equine Research Unit, School of Agriculture and Food Sciences, University of Queensland, Gatton, Queensland 4343, Australia
| | - Deborah Middleton
- New and Emerging Zoonotic Diseases, CSIRO, Australian Animal Health Laboratory, East Geelong, Victoria 3220, Australia
| | - Peter A Reid
- Equine Veterinary Surgeon, Brisbane, Queensland 4034, Australia
| | - Rosemary A McFarlane
- National Centre for Epidemiology and Population Health, Australian National University, Canberra 0200, Australia
| | - Gerardo Martin
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Queensland 4811, Australia
| | - Gary M Tabor
- Center for Large Landscape Conservation, Bozeman, MT 59771, USA
| | - Lee F Skerratt
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Queensland 4811, Australia
| | - Dale L Anderson
- Equine Research Unit, School of Agriculture and Food Sciences, University of Queensland, Gatton, Queensland 4343, Australia
| | - Gary Crameri
- New and Emerging Zoonotic Diseases, CSIRO, Australian Animal Health Laboratory, East Geelong, Victoria 3220, Australia
| | | | - David Jordan
- New South Wales Department of Primary Industries, 1423 Bruxner Highway, Wollongbar, New South Wales 2477, Australia
| | - Paul Freeman
- New South Wales Department of Primary Industries, 1423 Bruxner Highway, Wollongbar, New South Wales 2477, Australia
| | - Lin-Fa Wang
- New and Emerging Zoonotic Diseases, CSIRO, Australian Animal Health Laboratory, East Geelong, Victoria 3220, Australia Program in Emerging Infectious Diseases, Duke-NUS Graduate Medical School, Singapore 169857
| | | | - Glenn A Marsh
- New and Emerging Zoonotic Diseases, CSIRO, Australian Animal Health Laboratory, East Geelong, Victoria 3220, Australia
| | - Nina Y Kung
- Animal Biosecurity and Welfare Program, Biosecurity Queensland, Department of Agriculture, Fisheries and Forestry, Brisbane, Queensland 4001, Australia
| | - Hamish McCallum
- Griffith School of Environment, Griffith University, Brisbane 4111, Australia
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Tait J, Perotto-Baldivieso HL, McKeown A, Westcott DA. Are flying-foxes coming to town? Urbanisation of the spectacled flying-fox (Pteropus conspicillatus) in Australia. PLoS One 2014; 9:e109810. [PMID: 25295724 PMCID: PMC4190360 DOI: 10.1371/journal.pone.0109810] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 09/13/2014] [Indexed: 11/18/2022] Open
Abstract
Urbanisation of wildlife populations is a process with significant conservation and management implications. While urban areas can provide habitat for wildlife, some urbanised species eventually come into conflict with humans. Understanding the process and drivers of wildlife urbanisation is fundamental to developing effective management responses to this phenomenon. In Australia, flying-foxes (Pteropodidae) are a common feature of urban environments, sometimes roosting in groups of tens of thousands of individuals. Flying-foxes appear to be becoming increasingly urbanised and are coming into increased contact and conflict with humans. Flying-fox management is now a highly contentious issue. In this study we used monitoring data collected over a 15 year period (1998-2012) to examine the spatial and temporal patterns of association of spectacled flying-fox (Pteropus conspicillatus) roost sites (camps) with urban areas. We asked whether spectacled flying-foxes are becoming more urbanised and test the hypothesis that such changes are associated with anthropogenic changes to landscape structure. Our results indicate that spectacled flying-foxes were more likely to roost near humans than might be expected by chance, that over the period of the study the proportion of the flying-foxes in urban-associated camps increased, as did the number of urban camps. Increased urbanisation of spectacled flying-foxes was not related to changes in landscape structure or to the encroachment of urban areas on camps. Overall, camps tended to be found in areas that were more fragmented, closer to human habitation and with more urban land cover than the surrounding landscape. This suggests that urbanisation is a behavioural response rather than driven by habitat loss.
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Affiliation(s)
- Jessica Tait
- School of Energy, Environment and Agrifood, Cranfield University, Cranfield, Bedfordshire, United Kingdom
- CSIRO Sustainable Land and Water, Atherton, QLD, Australia
| | | | - Adam McKeown
- CSIRO Sustainable Land and Water, Smithfield, QLD, Australia
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Interdisciplinary approaches to understanding disease emergence: the past, present, and future drivers of Nipah virus emergence. Proc Natl Acad Sci U S A 2012; 110 Suppl 1:3681-8. [PMID: 22936052 DOI: 10.1073/pnas.1201243109] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Emerging infectious diseases (EIDs) pose a significant threat to human health, economic stability, and biodiversity. Despite this, the mechanisms underlying disease emergence are still not fully understood, and control measures rely heavily on mitigating the impact of EIDs after they have emerged. Here, we highlight the emergence of a zoonotic Henipavirus, Nipah virus, to demonstrate the interdisciplinary and macroecological approaches necessary to understand EID emergence. Previous work suggests that Nipah virus emerged due to the interaction of the wildlife reservoir (Pteropus spp. fruit bats) with intensively managed livestock. The emergence of this and other henipaviruses involves interactions among a suite of anthropogenic environmental changes, socioeconomic factors, and changes in demography that overlay and interact with the distribution of these pathogens in their wildlife reservoirs. Here, we demonstrate how ecological niche modeling may be used to investigate the potential role of a changing climate on the future risk for Henipavirus emergence. We show that the distribution of Henipavirus reservoirs, and therefore henipaviruses, will likely change under climate change scenarios, a fundamental precondition for disease emergence in humans. We assess the variation among climate models to estimate where Henipavirus host distribution is most likely to expand, contract, or remain stable, presenting new risks for human health. We conclude that there is substantial potential to use this modeling framework to explore the distribution of wildlife hosts under a changing climate. These approaches may directly inform current and future management and surveillance strategies aiming to improve pathogen detection and, ultimately, reduce emergence risk.
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Plowright RK, Foley P, Field HE, Dobson AP, Foley JE, Eby P, Daszak P. Urban habituation, ecological connectivity and epidemic dampening: the emergence of Hendra virus from flying foxes (Pteropus spp.). Proc Biol Sci 2011; 278:3703-12. [PMID: 21561971 DOI: 10.1098/rspb.2011.0522] [Citation(s) in RCA: 216] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Anthropogenic environmental change is often implicated in the emergence of new zoonoses from wildlife; however, there is little mechanistic understanding of these causal links. Here, we examine the transmission dynamics of an emerging zoonotic paramyxovirus, Hendra virus (HeV), in its endemic host, Australian Pteropus bats (fruit bats or flying foxes). HeV is a biosecurity level 4 (BSL-4) pathogen, with a high case-fatality rate in humans and horses. With models parametrized from field and laboratory data, we explore a set of probable contributory mechanisms that explain the spatial and temporal pattern of HeV emergence; including urban habituation and decreased migration-two widely observed changes in flying fox ecology that result from anthropogenic transformation of bat habitat in Australia. Urban habituation increases the number of flying foxes in contact with human and domestic animal populations, and our models suggest that, in addition, decreased bat migratory behaviour could lead to a decline in population immunity, giving rise to more intense outbreaks after local viral reintroduction. Ten of the 14 known HeV outbreaks occurred near urbanized or sedentary flying fox populations, supporting these predictions. We also demonstrate that by incorporating waning maternal immunity into our models, the peak modelled prevalence coincides with the peak annual spill-over hazard for HeV. These results provide the first detailed mechanistic framework for understanding the sporadic temporal pattern of HeV emergence, and of the urban/peri-urban distribution of HeV outbreaks in horses and people.
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Affiliation(s)
- Raina K Plowright
- Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, PA 16802, USA.
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ROBERTS BILLIEJ, CATTERALL CARLAP, EBY PEGGY, KANOWSKI JOHN. Latitudinal range shifts in Australian flying-foxes: A re-evaluation. AUSTRAL ECOL 2011. [DOI: 10.1111/j.1442-9993.2011.02243.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Baldwin HJ, Hoggard SJ, Snoyman ST, Stow AJ, Brown C. Non-invasive genetic sampling of faecal material and hair from the grey-headed flying-fox (Pteropus poliocephalus). AUSTRALIAN MAMMALOGY 2010. [DOI: 10.1071/am09015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Remote-sampling DNA from animals offers obvious benefits for species that are difficult to sample directly and is less disruptive for species of conservation concern. Here we report the results of a pilot study investigating non-invasive DNA sampling of the grey-headed flying-fox (Pteropus poliocephalus), a threatened species that is restricted to the east coast of Australia. We successfully extracted DNA from fresh scats and hair, each of which was of sufficient quality for amplifying mitochondrial DNA markers and microsatellites. A single-locus multitube approach was used to investigate amplification success and genotyping reliability. Faecal samples yielded a higher proportion of successful amplifications and consensus genotype assignments than hair samples. We outline measures that may be utilised to minimise microsatellite genotyping error for future studies. These indirect approaches to obtaining genetic data show much promise given the difficult nature of directly sampling flying-foxes and related species.
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Flaquer C, Puig-Montserrat X, Goiti U, Vidal F, Curcó A, Russo D. Habitat Selection in Nathusius' Pipistrelle (Pipistrellus nathusii): The Importance of Wetlands. ACTA CHIROPTEROLOGICA 2009. [DOI: 10.3161/150811009x465767] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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McClelland K. Challenges and recovery actions for the widespread, threatened Grey-headed Flying-fox: A review from a New South Wales policy perspective. ECOLOGICAL MANAGEMENT & RESTORATION 2009. [DOI: 10.1111/j.1442-8903.2009.00456.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Philbey AW, Kirkland PD, Ross AD, Field HE, Srivastava M, Davis RJ, Love RJ. Infection with Menangle virus in flying foxes (Pteropus spp.) in Australia. Aust Vet J 2009; 86:449-54. [PMID: 18959537 DOI: 10.1111/j.1751-0813.2008.00361.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To examine flying foxes (Pteropus spp.) for evidence of infection with Menangle virus. DESIGN Clustered non-random sampling for serology, virus isolation and electron microscopy (EM). PROCEDURE Serum samples were collected from 306 Pteropus spp. in northern and eastern Australia and tested for antibodies against Menangle virus (MenV) using a virus neutralisation test (VNT). Virus isolation was attempted from tissues and faeces collected from 215 Pteropus spp. in New South Wales. Faecal samples from 68 individual Pteropus spp. and four pools of faeces were examined by transmission EM following routine negative staining and immunogold labelling. RESULTS Neutralising antibodies (VNT titres > or = 8) against MenV were detected in 46% of black flying foxes (P. alecto), 41% of grey-headed flying foxes (P. poliocephalus), 25% of spectacled flying foxes (P. conspicillatus) and 1% of little red flying foxes (P. scapulatus) in Australia. Positive sera included samples collected from P. poliocephalus in a colony adjacent to a piggery that had experienced reproductive disease caused by MenV. Virus-like particles were observed by EM in faeces from Pteropus spp. and reactivity was detected in pooled faeces and urine by immunogold EM using sera from sows that had been exposed to MenV. Attempts to isolate the virus from the faeces and tissues from Pteropus spp. were unsuccessful. CONCLUSION Serological evidence of infection with MenV was detected in Pteropus spp. in Australia. Although virus-like particles were detected in faeces, no viruses were isolated from faeces, urine or tissues of Pteropus spp.
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Affiliation(s)
- A W Philbey
- New South Wales Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle NSW, Australia.
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Schmelitschek E, French K, Parry-Jones K. Fruit availability and utilisation by grey-headed flying foxes (Pteropodidae: Pteropus poliocephalus) in a human-modified environment on the south coast of New South Wales, Australia. WILDLIFE RESEARCH 2009. [DOI: 10.1071/wr08169] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Context. Extensive clearing and modification of habitat is likely to change many facets of the environment including climate and regional food resources. Such changes may result in changes in behaviour in highly mobile fauna, such as flying foxes.
Aims.The availability of fruit resources was examined to determine whether grey-headed flying foxes (Pteropus poliocephalus) have feeding preferences related to habitat or dietary items, and whether human usage of the land around the colony site has affected the resources available.
Methods. Fruit availability around a colony was monitored from December 2004 to March 2005. Night surveys and faecal analyses were undertaken to determine the distribution of feeding locations, the food species used and the food items consumed by P. poliocephalus.
Key results.The amount of food available per hectare in each habitat was similar. However, we found differences in the composition of food trees and the distribution of food resources within each habitat. Ficus species were a major resource with flying foxes observed feeding in figs during every survey and figs identified in droppings over the whole period. Human-modified habitats were used throughout the study period with flying foxes observed in small patches of vegetation and in individual trees without any nearby vegetation.
Conclusions. The need for maintaining vegetation, particularly Ficus species, in all areas where flying foxes are found, especially in human-modified habitats and rainforest remnants, is highlighted as this vegetation is of great importance to flying foxes. Other wildlife, such as birds and possums, may also benefit from the maintenance of this vegetation.
Implications. Through management of urban resources there is the potential to prevent future conflict situations arising between humans and wildlife, such as can be seen when flying fox colonies are in close proximity to houses.
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Brown GW, Scroggie MP, Choquenot D. Precision and accuracy of flyout counts of the common bent-wing bat (Miniopterus schreibersii). ACTA CHIROPTEROLOGICA 2008. [DOI: 10.3161/150811008x331162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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SHILTON LOUISEA, LATCH PETERJ, MCKEOWN ADAM, PERT PETINA, WESTCOTT DAVIDA. Landscape-scale redistribution of a highly mobile threatened species, Pteropus conspicillatus (Chiroptera, Pteropodidae), in response to Tropical Cyclone Larry. AUSTRAL ECOL 2008. [DOI: 10.1111/j.1442-9993.2008.01910.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Welbergen JA. Variation in twilight predicts the duration of the evening emergence of fruit bats from a mixed-species roost. Anim Behav 2008. [DOI: 10.1016/j.anbehav.2007.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Welbergen JA, Klose SM, Markus N, Eby P. Climate change and the effects of temperature extremes on Australian flying-foxes. Proc Biol Sci 2008; 275:419-25. [PMID: 18048286 PMCID: PMC2596826 DOI: 10.1098/rspb.2007.1385] [Citation(s) in RCA: 269] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Little is known about the effects of temperature extremes on natural systems. This is of increasing concern now that climate models predict dramatic increases in the intensity, duration and frequency of such extremes. Here we examine the effects of temperature extremes on behaviour and demography of vulnerable wild flying-foxes (Pteropus spp.). On 12 January 2002 in New South Wales, Australia, temperatures exceeding 42 degrees C killed over 3500 individuals in nine mixed-species colonies. In one colony, we recorded a predictable sequence of thermoregulatory behaviours (wing-fanning, shade-seeking, panting and saliva-spreading, respectively) and witnessed how 5-6% of bats died from hyperthermia. Mortality was greater among the tropical black flying-fox, Pteropus alecto (10-13%) than the temperate grey-headed flying-fox, Pteropus poliocephalus (less than 1%), and young and adult females were more affected than adult males (young, 23-49%; females, 10-15%; males, less than 3%). Since 1994, over 30000 flying-foxes (including at least 24500 P. poliocephalus) were killed during 19 similar events. Although P. alecto was relatively less affected, it is currently expanding its range into the more variable temperature envelope of P. poliocephalus, which increases the likelihood of die-offs occurring in this species. Temperature extremes are important additional threats to Australian flying-foxes and the ecosystem services they provide, and we recommend close monitoring of colonies where temperatures exceeding 42.0 degrees C are predicted. The effects of temperature extremes on flying-foxes highlight the complex implications of climate change for behaviour, demography and species survival.
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Paramyxoviruses in Bats. ZOO AND WILD ANIMAL MEDICINE 2008. [PMCID: PMC7152176 DOI: 10.1016/b978-141604047-7.50031-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Fox S, Luly J, Mitchell C, Maclean J, Westcott DA. Demographic indications of decline in the spectacled flying fox (Pteropus conspicillatus) on the Atherton Tablelands of northern Queensland. WILDLIFE RESEARCH 2008. [DOI: 10.1071/wr07127] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A lack of information about the spectacled flying fox (Pteropus conspicillatus) makes management and conservation of this vulnerable species difficult. The analysis of population dynamics using life-history traits and life tables is widely used in planning for the conservation and management of wildlife. In the present study, the first life table for any species of bat is provided and age estimates derived from counts of annual increments in tooth cementum rings are used to assess population trends and life-history traits in the spectacled flying fox on the Atherton Tablelands in north Queensland. As a result of high mortality, longevity was much shorter than expected from a theoretical basis. Life-table analyses suggest that the population experienced a 16% decrease during the 2 years of study. Absence of extended longevity to compensate for low reproductive output and delayed sexual maturity in ‘slow end’ mammal species such as P. conspicillatus reduces the window of opportunity for females to reproduce and adapt to changes in mortality rates. This study suggests that spectacled flying fox populations are sensitive to increased mortality and that reducing mortality rates should be the primary goal in conservation planning for P. conspicillatus.
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Forsyth DM, Scroggie MP, McDonald-Madden E. Accuracy and precision of grey-headed flying-fox (Pteropus poliocephalus) flyout counts. WILDLIFE RESEARCH 2006. [DOI: 10.1071/wr05029] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The principal method for estimating the abundance of bats in roosts is to count the number of bats exiting the roost at dusk (‘flyout counts’). We hypothesised that the accuracy and precision of flyout counts decrease non-linearly as the number of bats moving per unit of time increases, and that accuracy increases with observer experience. To test these hypotheses, we filmed grey-headed flying-foxes (Pteropus poliocephalus) exiting a roost in Melbourne on three consecutive evenings. The film was slowed and the number of flying-foxes flying-out in 30-s intervals was counted and assumed to be the true abundance. Thirteen other observers independently counted the number of flying-foxes flying-out in real time. We formulated our hypotheses into candidate models and compared support for these models using information-theoretic methods. Non-linear models had much greater support than linear models for all three flyouts. There was undercounting in two flyouts and overcounting in the third. There was good support for an effect of observer experience in one of the flyouts, but less support in the others. Precision declined as the true abundance increased in all three flyout counts. Our results indicate that accuracy, precision and observer effects vary with the dynamics of each flyout, and suggest that under some conditions flyout counts will often provide both inaccurate and imprecise estimates of abundance.
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Westcott D, McKeown A. Observer error in exit counts of flying-foxes (Pteropus spp.). WILDLIFE RESEARCH 2004. [DOI: 10.1071/wr03091] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Population estimation and monitoring is a fundamental component in the conservation management of any species. For species such as flying-foxes (Pteropus spp.) population estimation is complicated by the large number of animals involved, their mobility and the conditions under which counts are conducted. Because count results are used in the determination of management requirements, they are the focus of much critical attention. Despite this, while measures of the precision of fly-out counts of Pteropus spp. have been published, measures of their accuracy have not. In this paper we present an assessment of the accuracy and precision of observer counts of dusk fly-outs by comparing recordings of observers’ counts with a video of the same fly-out. Observer’s counts were significantly related to the video-count (rs = 0.69, P < 0.0001), with the average observer’s count underestimating the video-count by 14.7% (± 25, s.d.) of the video-count. Observers’ errors increased with the rate at which flying-foxes left the camp and with the width of the fly-out stream. These results suggest that while observers’ errors are inherent in dusk fly-out counts, these errors are manageable and relatively predictable. Other sources of error are likely to have a greater impact on the final population estimate at both camp and regional scales.
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McIlwee AP, Martin L. On the intrinsic capacity for increase of Australian flying-foxes (Pteropus spp., Megachiroptera). ACTA ACUST UNITED AC 2002. [DOI: 10.7882/az.2002.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kirkland PD, Love RJ, Philbey AW, Ross AD, Davis RJ, Hart KG. Epidemiology and control of Menangle virus in pigs. Aust Vet J 2001; 79:199-206. [PMID: 11301749 DOI: 10.1111/j.1751-0813.2001.tb14580.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To describe the epidemiology and eradication of Menangle virus infection in pigs. DESIGN Field observations and interventions, structured and unstructured serological surveys, prospective and cross-sectional serological studies and laboratory investigations. PROCEDURE Serum samples were collected from pigs at a 2600-sow intensive piggery in New South Wales that experienced an outbreak of reproductive disease in 1997. Serum samples were also collected from piggeries that received pigs from or supplied pigs to the affected piggery and from other piggeries in Australia. Serum and tissue samples were collected from pigs at piggeries experiencing reproductive disease in New South Wales. Sera and faeces were collected from grey-headed flying foxes (Pteropus poliocephalus) in the region of the affected piggery. Serum samples were tested for neutralising antibodies against Menangle virus. Virus isolation was attempted from faeces. RESULTS Following the outbreak of reproductive disease, sera from 96% of adult pigs at the affected piggery, including sows that produced affected litters, contained neutralising antibodies against Menangle virus. Neutralising antibodies were also detected in sera from 88% of finisher pigs at two piggeries receiving weaned pigs from the affected piggery. No evidence of Menangle virus infection was found in other piggeries in Australia. In cross-sectional studies at the affected piggery, colostral antibodies were undetectable in most pigs by 14 to 15 weeks of age. By slaughter age or entry to the breeding herd, 95% of pigs developed high antibody titres (> or = 128) against Menangle virus in the virus neutralisation test. Menangle virus was eradicated from the affected piggery following a program of serological testing and segregation. Neutralising antibodies against Menangle virus were also detected in P poliocephalus from two colonies in the vicinity of the affected piggery. Two piggery workers were infected with Menangle virus. There was no evidence of infection in cattle, sheep, birds, rodents, feral cats and a dog at the affected piggery. CONCLUSIONS Serological evidence of infection with Menangle virus was detected in pigs at a piggery that had experienced reproductive disease, in pigs at two associated piggeries and in fruit bats in the region of the piggery. Two humans were infected. The mode of transmission between pigs is unknown, but spread by faecal or urinary excretion is postulated. This virus can be eradicated by the segregation of pigs into discrete age groups.
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Affiliation(s)
- P D Kirkland
- New South Wales Agriculture, Elizabeth Macarthur Agricultural Institute, Menangle, New South Wales 2568.
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