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Rogers JGD, Plagányi ÉE, Babcock RC, Fletcher CS, Westcott DA. Improving coral cover using an integrated pest management framework. Ecol Appl 2023; 33:e2913. [PMID: 37615222 DOI: 10.1002/eap.2913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 06/15/2023] [Accepted: 07/14/2023] [Indexed: 08/25/2023]
Abstract
Integrated pest management (IPM) leverages our understanding of ecological interactions to mitigate the impact of pest species on economically and/or ecologically important assets. It has primarily been applied in terrestrial settings (e.g., agriculture), but has rarely been attempted for marine ecosystems. The crown-of-thorns starfish (CoTS), Acanthaster spp., is a voracious coral predator throughout the Indo-Pacific where it undergoes large population increases (irruptions), termed outbreaks. During outbreaks CoTS act as a pest species and can result in substantial coral loss. Contemporary management of CoTS on the Great Barrier Reef (GBR) adopts facets of the IPM paradigm to manage these outbreaks through strategic use of direct manual control (culling) of individuals in response to ecologically based target thresholds. There has, however, been limited quantitative analysis of how to optimize the implementation of such thresholds. Here we use a multispecies modeling approach to assess the performance of alternative CoTS management scenarios for improving coral cover trajectories. The scenarios examined varied in terms of their ecological threshold target, the sensitivity of the threshold, and the level of management resourcing. Our approach illustrates how to quantify multidimensional trade-offs in resourcing constraints, concurrent CoTS and coral population dynamics, the stringency of target thresholds, and the geographical scale of management outcomes (number of sites). We found strategies with low target density thresholds for CoTS (≤0.03 CoTS min-1 ) could act as "Effort Sinks" and limit the number of sites that could be effectively controlled, particularly under CoTS population outbreaks. This was because a handful of sites took longer to control, which meant other sites were not controlled. Higher density thresholds (e.g., 0.04-0.08 CoTS min-1 ), tuned to levels of coral cover, diluted resources among sites but were more robust to resourcing constraints and pest population dynamics. Our study highlights trade-off decisions when using an IPM framework and informs the implementation of threshold-based strategies on the GBR.
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Affiliation(s)
- Jacob G D Rogers
- School of Mathematics and Physics, University of Queensland, Brisbane, Queensland, Australia
- CSIRO Oceans and Atmosphere, Brisbane, Queensland, Australia
| | - Éva E Plagányi
- CSIRO Oceans and Atmosphere, Brisbane, Queensland, Australia
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2
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Lloyd-Jones LR, Bravington MV, Armstrong KN, Lawrence E, Feutry P, Todd CM, Dorrestein A, Welbergen JA, Martin JM, Rose K, Hall J, Phalen DN, Peters I, Baylis SM, Macgregor NA, Westcott DA. Close-kin mark-recapture informs critically endangered terrestrial mammal status. Sci Rep 2023; 13:12512. [PMID: 37532795 PMCID: PMC10397353 DOI: 10.1038/s41598-023-38639-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 07/12/2023] [Indexed: 08/04/2023] Open
Abstract
Reliable information on population size is fundamental to the management of threatened species. For wild species, mark-recapture methods are a cornerstone of abundance estimation. Here, we show the first application of the close-kin mark-recapture (CKMR) method to a terrestrial species of high conservation value; the Christmas Island flying-fox (CIFF). The CIFF is the island's last remaining native terrestrial mammal and was recently listed as critically endangered. CKMR is a powerful tool for estimating the demographic parameters central to CIFF management and circumvents the complications arising from the species' cryptic nature, mobility, and difficult-to-survey habitat. To this end, we used genetic data from 450 CIFFs captured between 2015 and 2019 to detect kin pairs. We implemented a novel CKMR model that estimates sex-specific abundance, trend, and mortality and accommodates observations from the kin-pair distribution of male reproductive skew and mate persistence. CKMR estimated CIFF total adult female abundance to be approximately 2050 individuals (95% CI (950, 4300)). We showed that on average only 23% of the adult male population contributed to annual reproduction and strong evidence for between-year mate fidelity, an observation not previously quantified for a Pteropus species in the wild. Critically, our population estimates provide the most robust understanding of the status of this critically endangered population, informing immediate and future conservation initiatives.
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Affiliation(s)
- Luke R Lloyd-Jones
- Commonwealth Scientific and Industrial Research Organisation, Data61, Brisbane, QLD, 4072, Australia.
| | - Mark V Bravington
- Commonwealth Scientific and Industrial Research Organisation, Data61, Hobart, TAS, 7000, Australia
| | - Kyle N Armstrong
- Environment Institute, University of Adelaide, North Terrace, Adelaide, South Australia, 5005, Australia
| | - Emma Lawrence
- Commonwealth Scientific and Industrial Research Organisation, Data61, Brisbane, QLD, 4072, Australia
| | - Pierre Feutry
- Commonwealth Scientific and Industrial Research Organisation, Oceans and Atmosphere, Hobart, TAS, 7000, Australia
| | - Christopher M Todd
- The Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
| | - Annabel Dorrestein
- The Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
| | - Justin A Welbergen
- The Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
| | - John M Martin
- The Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, Australia
- Royal Botanic Gardens and Domain Trust, Sydney, NSW, 2000, Australia
- Australian Registry of Wildlife Health, Taronga Conservation Society Australia, Bradleys Head Road, Mosman, NSW, 2088, Australia
| | - Karrie Rose
- Australian Registry of Wildlife Health, Taronga Conservation Society Australia, Bradleys Head Road, Mosman, NSW, 2088, Australia
| | - Jane Hall
- Australian Registry of Wildlife Health, Taronga Conservation Society Australia, Bradleys Head Road, Mosman, NSW, 2088, Australia
| | - David N Phalen
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, Sydney, NSW, 2006, Australia
| | - Isabel Peters
- School of Mathematics and Physics, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Shane M Baylis
- Commonwealth Scientific and Industrial Research Organisation, Oceans and Atmosphere, Hobart, TAS, 7000, Australia
| | - Nicholas A Macgregor
- Parks Australia, Canberra, ACT, 2601, Australia
- Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury, CT2 7NR, Kent, UK
| | - David A Westcott
- Land and Water, Commonwealth Scientific and Industrial Research Organisation, Atherton, QLD, 4883, Australia
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3
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Lloyd‐Jones LR, Brien ML, Feutry P, Lawrence E, Beri P, Booth S, Coulson S, Baylis SM, Villiers K, Taplin LE, Westcott DA. Implications of past and present genetic connectivity for management of the saltwater crocodile (
Crocodylus porosus
). Evol Appl 2023; 16:911-935. [PMID: 37124084 PMCID: PMC10130557 DOI: 10.1111/eva.13545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 02/17/2023] [Accepted: 03/16/2023] [Indexed: 04/03/2023] Open
Abstract
Effective management of protected species requires information on appropriate evolutionary and geographic population boundaries and knowledge of how the physical environment and life-history traits combine to shape the population structure and connectivity. Saltwater crocodiles (Crocodylus porosus) are the largest and most widely distributed of living crocodilians, extending from Sri Lanka to Southeast Asia and down to northern Australia. Given the long-distance movement capabilities reported for C. porosus, management units are hypothesised to be highly connected by migration. However, the magnitude, scale, and consistency of connection across managed populations are not fully understood. Here we used an efficient genotyping method that combines DArTseq and sequence capture to survey ≈ 3000 high-quality genome-wide single nucleotide polymorphisms from 1176 C. porosus sampled across nearly the entire range of the species in Queensland, Australia. We investigated historical and present-day connectivity patterns using fixation and diversity indices coupled with clustering methods and the spatial distribution of kin pairs. We inferred kinship using forward simulation coupled with a kinship estimation method that is robust to unspecified population structure. The results demonstrated that the C. porosus population has substantial genetic structure with six broad populations correlated with geographical location. The rate of gene flow was highly correlated with spatial distance, with greater differentiation along the east coast compared to the west. Kinship analyses revealed evidence of reproductive philopatry and limited dispersal, with approximately 90% of reported first and second-degree relatives showing a pairwise distance of <50 km between sampling locations. Given the limited dispersal, lack of suitable habitat, low densities of crocodiles and the high proportion of immature animals in the population, future management and conservation interventions should be considered at regional and state-wide scales.
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Affiliation(s)
- Luke R. Lloyd‐Jones
- Commonwealth Scientific and Industrial Research Organisation Data61 Brisbane Queensland 4072 Australia
| | - Matthew L. Brien
- Department of Environment and Science Queensland Government Cairns Queensland 4870 Australia
| | - Pierre Feutry
- Commonwealth Scientific and Industrial Research Organisation Oceans and Atmosphere Hobart Tasmania 7000 Australia
| | - Emma Lawrence
- Commonwealth Scientific and Industrial Research Organisation Data61 Brisbane Queensland 4072 Australia
| | - Paul Beri
- Department of Environment and Science Queensland Government Cairns Queensland 4870 Australia
| | - Simon Booth
- Department of Environment and Science Queensland Government Cairns Queensland 4870 Australia
| | - Steven Coulson
- Department of Environment and Science Queensland Government Cairns Queensland 4870 Australia
| | - Shane M. Baylis
- Commonwealth Scientific and Industrial Research Organisation Oceans and Atmosphere Hobart Tasmania 7000 Australia
| | - Kira Villiers
- Commonwealth Scientific and Industrial Research Organisation Data61 Brisbane Queensland 4072 Australia
| | - Laurence E. Taplin
- Department of Environment and Science Queensland Government Cairns Queensland 4870 Australia
| | - David A. Westcott
- Commonwealth Scientific and Industrial Research Organisation Land and Water Atherton Queensland 4883 Australia
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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. Sci Total Environ 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Todd CM, Westcott DA, Martin JM, Rose K, McKeown A, Hall J, Welbergen JA. Body-size dependent foraging strategies in the Christmas Island flying-fox: implications for seed and pollen dispersal within a threatened island ecosystem. Mov Ecol 2022; 10:19. [PMID: 35410304 PMCID: PMC8996557 DOI: 10.1186/s40462-022-00315-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Animals are important vectors for the dispersal of a wide variety of plant species, and thus play a key role in maintaining the health and biodiversity of natural ecosystems. On oceanic islands, flying-foxes are often the only seed dispersers or pollinators. However, many flying-fox populations are currently in decline, particularly those of insular species, and this has consequences for the ecological services they provide. Knowledge of the drivers and the scale of flying-fox movements is important in determining the ecological roles that flying-foxes play on islands. This information is also useful for understanding the potential long-term consequences for forest dynamics resulting from population declines or extinction, and so can aid in the development of evidence-based ecological management strategies. To these ends, we examined the foraging movements, floral resource use, and social interactions of the Critically Endangered Christmas Island flying-fox (Pteropus natalis). METHODS Utilization distributions, using movement-based kernel estimates (MBKE) were generated to determine nightly foraging movements of GPS-tracked P. natalis (n = 24). Generalized linear models (GLMs), linear mixed-effect models (LMMs), and Generalized linear mixed-effects model (GLMMs) were constructed to explain how intrinsic factors (body mass, skeletal size, and sex) affected the extent of foraging movements. In addition, we identified pollen collected from facial and body swabs of P. natalis (n = 216) to determine foraging resource use. Direct observations (n = 272) of foraging P. natalis enabled us to assess the various behaviors used to defend foraging resources. RESULTS Larger P. natalis individuals spent more time foraging and less time traveling between foraging patches, traveled shorter nightly distances, and had smaller overall foraging ranges than smaller conspecifics. Additionally, larger individuals visited a lower diversity of floral resources. CONCLUSIONS Our findings suggest that smaller P. natalis individuals are the primary vectors of long-distance dispersal of pollen and digested seeds in this species, providing a vital mechanism for maintaining the flow of plant genetic diversity across Christmas Island. Overall, our study highlights the need for more holistic research approaches that incorporate population demographics when assessing a species' ecological services.
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Affiliation(s)
- Christopher M. Todd
- The Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW 2753 Australia
| | - David A. Westcott
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), 47-67 Maunds St, Atherton, QLD 4883 Australia
- Atherton, Australia
| | - John M. Martin
- Taronga Institute of Science and Learning, Taronga Conservation Society Australia, Bradleys Head Rd, Mosman, NSW 2088 Australia
| | - Karrie Rose
- Taronga Institute of Science and Learning, Taronga Conservation Society Australia, Bradleys Head Rd, Mosman, NSW 2088 Australia
| | - Adam McKeown
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Waite Rd, Urrbrae, SA 5064 Australia
| | - Jane Hall
- Taronga Institute of Science and Learning, Taronga Conservation Society Australia, Bradleys Head Rd, Mosman, NSW 2088 Australia
| | - Justin A. Welbergen
- The Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW 2753 Australia
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6
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Condie SA, Anthony KRN, Babcock RC, Baird ME, Beeden R, Fletcher CS, Gorton R, Harrison D, Hobday AJ, Plagányi ÉE, Westcott DA. Large-scale interventions may delay decline of the Great Barrier Reef. R Soc Open Sci 2021; 8:201296. [PMID: 34007456 PMCID: PMC8080001 DOI: 10.1098/rsos.201296] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 03/31/2021] [Indexed: 05/31/2023]
Abstract
On the iconic Great Barrier Reef (GBR), the cumulative impacts of tropical cyclones, marine heatwaves and regular outbreaks of coral-eating crown-of-thorns starfish (CoTS) have severely depleted coral cover. Climate change will further exacerbate this situation over the coming decades unless effective interventions are implemented. Evaluating the efficacy of alternative interventions in a complex system experiencing major cumulative impacts can only be achieved through a systems modelling approach. We have evaluated combinations of interventions using a coral reef meta-community model. The model consisted of a dynamic network of 3753 reefs supporting communities of corals and CoTS connected through ocean larval dispersal, and exposed to changing regimes of tropical cyclones, flood plumes, marine heatwaves and ocean acidification. Interventions included reducing flood plume impacts, expanding control of CoTS populations, stabilizing coral rubble, managing solar radiation and introducing heat-tolerant coral strains. Without intervention, all climate scenarios resulted in precipitous declines in GBR coral cover over the next 50 years. The most effective strategies in delaying decline were combinations that protected coral from both predation (CoTS control) and thermal stress (solar radiation management) deployed at large scale. Successful implementation could expand opportunities for climate action, natural adaptation and socioeconomic adjustment by at least one to two decades.
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Affiliation(s)
- Scott A. Condie
- CSIRO Oceans and Atmosphere, Hobart, Tasmania, Australia
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
| | - Kenneth R. N. Anthony
- Australian Institute of Marine Science, Townsville, Queensland, Australia
- School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Russ C. Babcock
- CSIRO Oceans and Atmosphere, Brisbane, Queensland, Australia
| | - Mark E. Baird
- CSIRO Oceans and Atmosphere, Hobart, Tasmania, Australia
| | - Roger Beeden
- Great Barrier Reef Marine Park Authority, Townsville, Queensland, Australia
| | | | - Rebecca Gorton
- CSIRO Oceans and Atmosphere, Hobart, Tasmania, Australia
| | - Daniel Harrison
- National Marine Science Centre, Southern Cross University, Coffs Harbour, New South Wales, Australia
- Marine Studies Centre, School of Geosciences, University of Sydney, Camperdown, New South Wales, Australia
| | - Alistair J. Hobday
- CSIRO Oceans and Atmosphere, Hobart, Tasmania, Australia
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
| | - Éva E. Plagányi
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
- CSIRO Oceans and Atmosphere, Brisbane, Queensland, Australia
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7
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Boardman WSJ, Roshier D, Reardon T, Burbidge K, McKeown A, Westcott DA, Caraguel CGB, Prowse TAA. Spring foraging movements of an urban population of grey-headed flying foxes ( Pteropus poliocephalus). Journal of Urban Ecology 2021. [DOI: 10.1093/jue/juaa034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Flying foxes provide ecologically and economically important ecosystem services but extensive clearing and modification of habitat and drought combined with the planting of commercial and non-commercial trees across various landscapes, has meant flying foxes in Australia are increasingly seeking foraging resources in new areas. In 2011, grey-headed flying foxes formed a camp in Adelaide, South Australia, outside their previously recorded range. We used global positioning system telemetry to study the movements and foraging behaviour of this species in Adelaide in spring (September to November) 2015. High-frequency location data were used to determine the foraging range and the most frequently visited foraging sites used by each bat which were ground-truthed to identify forage plants. A total of 7239 valid locations were collected over 170 nights from four collars. Despite being a highly mobile species, the mean core foraging range estimate was only 7.30 km2 (range 3.3–11.2 km2). Maximum foraging distance from the camp in the Botanic Park was 9.5 km but most foraging occurred within a 4-km radius. The most common foraging sites occurred within the residential area of Adelaide and included introduced forage plant species, Lemon-scented gum (Corymbia citriodora) and Port Jackson fig (Ficus rubiginosa). Other observed movement activities included dipping behaviour on inland and marine waters and travel across flight paths around Adelaide airport. Our findings suggest that urban habitats in Adelaide provide sufficient foraging resources for grey-headed flying foxes to use these areas exclusively, at least in spring. This creates substantial opportunities for bats to interact with humans and their infrastructure.
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Affiliation(s)
- Wayne S J Boardman
- Department of Pathobiology, Infectious Disease and Public Health, School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy, SA 5371, Australia
| | - David Roshier
- Australian Wildlife Conservancy, Subiaco, WA 6008, Australia
| | - Terry Reardon
- South Australia Museum, Adelaide, SA 5000, Australia
| | - Kathryn Burbidge
- Department of Pathobiology, Infectious Disease and Public Health, School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy, SA 5371, Australia
| | - Adam McKeown
- CSIRO Land and Water, Atherton, QLD 4883, Australia
| | | | - Charles G B Caraguel
- Department of Pathobiology, Infectious Disease and Public Health, School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy, SA 5371, Australia
| | - Thomas A A Prowse
- Department of Ecology and Evolutionary Biology, School of Biological Sciences, Adelaide, SA 5000, Australia
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8
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Kroon FJ, Lefèvre CD, Doyle JR, Patel F, Milton G, Severati A, Kenway M, Johansson CL, Schnebert S, Thomas-Hall P, Bonin MC, Cameron DS, Westcott DA. DNA-based identification of predators of the corallivorous Crown-of-Thorns Starfish (Acanthaster cf. solaris) from fish faeces and gut contents. Sci Rep 2020; 10:8184. [PMID: 32424321 PMCID: PMC7235266 DOI: 10.1038/s41598-020-65136-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 04/28/2020] [Indexed: 11/10/2022] Open
Abstract
The corallivorous Crown-of-Thorns Starfish (CoTS, Acanthaster spp.) has been linked with the widespread loss of scleractinian coral cover on Indo-Pacific reefs during periodic population outbreaks. Here, we re-examine CoTS consumption by coral reef fish species by using new DNA technologies to detect Pacific Crown-of-Thorns Starfish (Acanthaster cf. solaris) in fish faecal and gut content samples. CoTS DNA was detected in samples from 18 different coral reef fish species collected on reefs at various stages of CoTS outbreaks in the Great Barrier Reef Marine Park, nine of which had not been previously reported to feed on CoTS. A comprehensive set of negative and positive control samples confirmed that our collection, processing and analysis procedures were robust, although food web transfer of CoTS DNA cannot be ruled out for some fish species. Our results, combined with the (i) presence of CoTS spines in some samples, (ii) reported predation on CoTS gametes, larvae and settled individuals, and (iii) known diet information for fish species examined, strongly indicate that direct fish predation on CoTS may well be more common than is currently appreciated. We provide recommendations for specific management approaches to enhance predation on CoTS by coral reef fishes, and to support the mitigation of CoTS outbreaks and reverse declines in hard coral cover.
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Affiliation(s)
- Frederieke J Kroon
- Australian Institute of Marine Science, Townsville, Qld, 4810, Australia.
| | - Carine D Lefèvre
- Australian Institute of Marine Science, Townsville, Qld, 4810, Australia
| | - Jason R Doyle
- Australian Institute of Marine Science, Townsville, Qld, 4810, Australia
| | - Frances Patel
- Australian Institute of Marine Science, Townsville, Qld, 4810, Australia
| | - Grant Milton
- Australian Institute of Marine Science, Townsville, Qld, 4810, Australia
| | - Andrea Severati
- Australian Institute of Marine Science, Townsville, Qld, 4810, Australia
| | - Matt Kenway
- Australian Institute of Marine Science, Townsville, Qld, 4810, Australia
| | | | - Simon Schnebert
- Australian Institute of Marine Science, Townsville, Qld, 4810, Australia
| | - Peter Thomas-Hall
- Australian Institute of Marine Science, Townsville, Qld, 4810, Australia
| | - Mary C Bonin
- Great Barrier Reef Marine Park Authority, Townsville, Qld, 4810, Australia
| | - Darren S Cameron
- Great Barrier Reef Marine Park Authority, Townsville, Qld, 4810, Australia
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9
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Schaer J, Boardman WSJ, McKeown A, Westcott DA, Matuschewski K, Power M. Molecular investigation of Hepatocystis parasites in the Australian flying fox Pteropus poliocephalus across its distribution range. Infect Genet Evol 2019; 75:103978. [PMID: 31352147 DOI: 10.1016/j.meegid.2019.103978] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 07/08/2019] [Accepted: 07/23/2019] [Indexed: 11/30/2022]
Abstract
Phylogenetic inference of Hepatocystis, a haemosporidian parasite of diverse primate and bat hosts, revealed that the parasites from Australasian Pteropus bat species form a distinct clade to all other Hepatocystis parasites from Africa and Asia. Here, we investigate the phylogenetic placement of Hepatocystis in the Australian bat Pteropus poliocephalus for the first time and examine parasite morphology and prevalence from selected points across its range. Hepatocystis infections were detected in low prevalences in P. poliocephalus in contrast to high numbers in P. alecto and P. scapulatus. The prevalence in P. poliocephalus varied across its distribution range with 15% in the central biogeographic areas (central Queensland and New South Wales) and 1% in the southern-most edge (South Australia) of its range. Sequencing of five genes revealed high genetic similarity in Hepatocystis of P. poliocephalus independent of sampling location. Phylogenetic analysis placed these parasites with Hepatocystis from other Pteropus species from Australia and Asia. While numerous haplotypes were identified among sequences from the Pteropus hosts, no patterns of host specificity were recovered within the Pteropus-specific parasite group.
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Affiliation(s)
- Juliane Schaer
- Dept. of Biological Sciences, Macquarie University, North Ryde, NSW, Australia; Museum für Naturkunde, Leibniz Institute for Research on Evolution, Berlin, Germany; Dept. of Molecular Parasitology, Institute of Biology, Humboldt University, Berlin, Germany.
| | - Wayne S J Boardman
- School of Animal and Veterinary Sciences, University of Adelaide, South Australia, Australia
| | - Adam McKeown
- CSIRO Land & Water, Cairns, Queensland 4878, Australia
| | | | - Kai Matuschewski
- Dept. of Molecular Parasitology, Institute of Biology, Humboldt University, Berlin, Germany
| | - Michelle Power
- Dept. of Biological Sciences, Macquarie University, North Ryde, NSW, Australia
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Dorrestein A, Todd CM, Westcott DA, Martin JM, Welbergen JA. Impacts of an invasive ant species on roosting behavior of an island endemic flying-fox. Biotropica 2019. [DOI: 10.1111/btp.12620] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Annabel Dorrestein
- Hawkesbury Institute for the Environment; Western Sydney University; Richmond New South Wales Australia
- Animal Ecology; Utrecht University; Utrecht The Netherlands
| | - Christopher M. Todd
- Hawkesbury Institute for the Environment; Western Sydney University; Richmond New South Wales Australia
| | | | - John M. Martin
- Royal Botanic Gardens and Domain Trust; Sydney New South Wales Australia
| | - Justin A. Welbergen
- Hawkesbury Institute for the Environment; Western Sydney University; Richmond New South Wales Australia
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11
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Todd CM, Westcott DA, Rose K, Martin JM, Welbergen JA. Slow growth and delayed maturation in a Critically Endangered insular flying fox ( Pteropus natalis). J Mammal 2018; 99:1510-1521. [PMID: 30538341 PMCID: PMC6283735 DOI: 10.1093/jmammal/gyy110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 08/24/2018] [Indexed: 11/14/2022] Open
Abstract
Flying foxes (family Pteropodidae) have distinct life histories given their size, characterized by longevity, low reproductive output, and long gestation. However, they tend to decouple the age at which sexual maturity is reached from the age at which they reach adult dimensions. We examined growth, maturation, and reproduction in the Critically Endangered Christmas Island flying fox (Pteropus natalis) to determine the timing of sex-specific life cycle events and patterns of growth. We estimated that juvenile growth in forearm length and body mass increased at a mean rate of 0.029 ± 0.005 mm/day and 0.33 ± 0.07 g/day for both males and females alike. Using these growth rates, we determined that the birth of pups occurs between December and March, with young becoming volant between June and August. The age at maturation for P. natalis is one of the oldest among all bat species. Juvenile males began to mature 15 months after birth and reached maturity 27 months after birth. Females reached maturity 24 months after birth at a significantly smaller body mass (3.6%) and forearm length (1.4%) than males. Significant sexual dimorphism and bimaturation was observed, with juvenile males being 1.5% and adult males being 1.9% larger on average than females for skeletal dimensions only. Growth and maturation are even slower in P. natalis than in the few other Pteropus species studied to date. The slow growth and delayed maturation of P. natalis imply slower potential population growth rates, further complicating the recovery of this Critically Endangered single-island endemic.
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Affiliation(s)
- Christopher M Todd
- The Hawkesbury institute for the Environment, Western Sydney University, Richmond, New South Wales, Australia
| | - David A Westcott
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Land and Water, Maunds St. Atherton, Queensland, Australia
| | - Karrie Rose
- Taronga Conservation Society Australia, Australian Registry Wildlife Health, Mosman, New South Wales, Australia
| | - John M Martin
- Royal Botanic Gardens and Domain Trust, Mrs Macquaries Road, Sydney, New South Wales, Australia
| | - Justin A Welbergen
- The Hawkesbury institute for the Environment, Western Sydney University, Richmond, New South Wales, Australia
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12
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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13
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Westcott DA, Caley P, Heersink DK, McKeown A. A state-space modelling approach to wildlife monitoring with application to flying-fox abundance. Sci Rep 2018; 8:4038. [PMID: 29511249 PMCID: PMC5840426 DOI: 10.1038/s41598-018-22294-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 02/06/2018] [Indexed: 11/13/2022] Open
Abstract
Monitoring flying-foxes is challenging as their extreme mobility produces highly dynamic population processes, considerable logistic difficulty, and variability in estimated population size. We report on methods for inferring population trend for the population of the spectacled flying-fox (Pteropus conspicillatus) in Australia. Monthly monitoring is conducted at all known roost sites across the species’ range in the Wet Tropics Region. The proportion of animals in camps varies seasonally and stochastic environmental events appear to be influential. We develop a state-space model that incorporates these processes and enables inference on total population trends and uses early warning analysis to identify the causes of population dynamics. The model suggests that population growth rate is stable in the absence of cyclones, however, cyclones appear to impact on both survival and reproduction. The population recovered after two cyclones but declined after a third. The modelling estimates a population decline over 15 years of c. 75% (mean r = − 0.12yr−1 and belief of negative trend is c. 83%) suggesting that conservation action is warranted. Our work shows that a state-space modelling approach is a significant improvement on inference from raw counts from surveys and demonstrates that this approach is a workable alternative to other methods.
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Affiliation(s)
- David A Westcott
- CSIRO Land and Water, PO Box 780, Atherton, Queensland, Australia.
| | - Peter Caley
- CSIRO Data61, GPO Box 1700, Canberra, ACT 2601, Australia
| | | | - Adam McKeown
- CSIRO Land and Water, PO Box 12139, Earlville BC, Qld, 4870, Australia
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14
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Phiphatsuwannachai S, Westcott DA, McKeown A, Savini T. Inter-group variability in seed dispersal by white-handed gibbons in mosaic forest. Biotropica 2017. [DOI: 10.1111/btp.12499] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Suchada Phiphatsuwannachai
- Conservation Ecology Program; School of Bioresourses and Technology; King Mongkut's University of Technology Thonburi; Bangkok Thailand
| | | | - Adam McKeown
- CSIRO Land and Water; PO Box 780 Atherton 4883 Queensland Australia
| | - Tommaso Savini
- Conservation Ecology Program; School of Bioresourses and Technology; King Mongkut's University of Technology Thonburi; Bangkok Thailand
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15
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Pratchett MS, Cowan ZL, Nadler LE, Caballes CF, Hoey AS, Messmer V, Fletcher CS, Westcott DA, Ling SD. Body size and substrate type modulate movement by the western Pacific crown-of-thorns starfish, Acanthaster solaris. PLoS One 2017; 12:e0180805. [PMID: 28877193 PMCID: PMC5587101 DOI: 10.1371/journal.pone.0180805] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 06/21/2017] [Indexed: 11/25/2022] Open
Abstract
The movement capacity of the crown-of-thorns starfishes (Acanthaster spp.) is a primary determinant of both their distribution and impact on coral assemblages. We quantified individual movement rates for the Pacific crown-of-thorns starfish (Acanthaster solaris) ranging in size from 75–480 mm total diameter, across three different substrates (sand, flat consolidated pavement, and coral rubble) on the northern Great Barrier Reef. The mean (±SE) rate of movement for smaller (<150 mm total diameter) A. solaris was 23.99 ± 1.02 cm/ min and 33.41 ± 1.49 cm/ min for individuals >350 mm total diameter. Mean (±SE) rates of movement varied with substrate type, being much higher on sand (36.53 ± 1.31 cm/ min) compared to consolidated pavement (28.04 ± 1.15 cm/ min) and slowest across coral rubble (17.25 ± 0.63 cm/ min). If average rates of movement measured here can be sustained, in combination with strong directionality, displacement distances of adult A. solaris could range from 250–520 m/ day, depending on the prevailing substrate. Sustained movement of A. solaris is, however, likely to be highly constrained by habitat heterogeneity, energetic constraints, resource availability, and diurnal patterns of activity, thereby limiting their capacity to move between reefs or habitats.
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Affiliation(s)
- Morgan S. Pratchett
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
- * E-mail:
| | - Zara-Louise Cowan
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
| | - Lauren E. Nadler
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, United States of America
| | - Ciemon F. Caballes
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
| | - Andrew S. Hoey
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
| | - Vanessa Messmer
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
| | | | | | - Scott D. Ling
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia
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16
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McLean WR, Goldingay RL, Westcott DA. Visual lures increase camera-trap detection of the southern cassowary (Casuarius casuarius johnsonii). Wildl Res 2017. [DOI: 10.1071/wr16025] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Context Monitoring is a key component in managing wildlife populations and is critical for revealing long-term population trends of endangered species. Cryptic or highly mobile species that occur in low densities and in remote terrain require the development of specific monitoring methods. The southern cassowary is an Australian endangered species that poses many challenges for conducting population surveys. Aims The aims of the present study were to determine the effectiveness of camera traps in detecting cassowaries at a site, to determine whether visual lures increased detection rates, and to explore the potential of camera traps in population surveys. Methods Coloured lures (mimicking large blue and red fruit) were placed in front of a set of camera traps and compared with controls (no lures) at 29 survey sites on the Daintree coast, northern Queensland, Australia. Key results Camera traps with lures (1) detected more birds, (2) had a shorter detection latency, (3) had a marginally greater number of captures, (4) experienced a longer capture duration, (5) were more likely to have the cassowary stop in front of the camera, and (6) achieved a 95% probability of detecting cassowaries in 12 trap days, compared with 28 trap days without lures. Conclusions An increase in the number of cassowaries detected, the reduction in camera latency times and the ability to identify the birds enables a more efficient approach to estimating population sizes over existing methods. This is the first published study to use visual lures to conduct camera trapping of birds. Implications The use of camera traps with lures is a practical and cost-efficient technique for the rapid detection of cassowaries at a site and lends itself to studies of population structure, size and trends.
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17
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Hook SE, Kroon FJ, Metcalfe S, Greenfield PA, Moncuquet P, McGrath A, Smith R, Warne MSJ, Turner RD, McKeown A, Westcott DA. Global transcriptomic profiling in barramundi (Lates calcarifer) from rivers impacted by differing agricultural land uses. Environ Toxicol Chem 2017; 36:103-112. [PMID: 27219023 DOI: 10.1002/etc.3505] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 11/23/2015] [Accepted: 05/22/2016] [Indexed: 06/05/2023]
Abstract
Most catchments discharging into the Great Barrier Reef lagoon have elevated loads of suspended sediment, nutrients, and pesticides, including photosystem II inhibiting herbicides, associated with upstream agricultural land use. To investigate potential impacts of declining water quality on fish physiology, RNA sequencing (RNASeq) was used to characterize and compare the hepatic transcriptomes of barramundi (Lates calcarifer) captured from 2 of these tropical river catchments in Queensland, Australia. The Daintree and Tully Rivers differ in upstream land uses, as well as sediment, nutrient, and pesticide loads, with the area of agricultural land use and contaminant loads lower in the Daintree. In fish collected from the Tully River, transcripts involved in fatty acid metabolism, amino acid metabolism, and citrate cycling were also more abundant, suggesting elevated circulating cortisol concentrations, whereas transcripts involved in immune responses were less abundant. Fish from the Tully also had an increased abundance of transcripts associated with xenobiotic metabolism. Previous laboratory-based studies observed similar patterns in fish and amphibians exposed to the agricultural herbicide atrazine. If these transcriptomic patterns are manifested at the whole organism level, the differences in water quality between the 2 rivers may alter fish growth and fitness. Environ Toxicol Chem 2017;36:103-112. © 2016 SETAC.
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Affiliation(s)
- Sharon E Hook
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Kirrawee, New South Wales, Australia
| | - Frederieke J Kroon
- Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - Suzanne Metcalfe
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Dutton Park, Queensland, Australia
| | - Paul A Greenfield
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, New South Wales, Australia
| | - Philippe Moncuquet
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Acton, Australian Capital Territory, Australia
| | - Annette McGrath
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Acton, Australian Capital Territory, Australia
| | - Rachael Smith
- Queensland Department of Science, Information Technology, and Innovation, Brisbane, Queensland, Australia
| | - Michael St J Warne
- Queensland Department of Science, Information Technology, and Innovation, Brisbane, Queensland, Australia
| | - Ryan D Turner
- Queensland Department of Science, Information Technology, and Innovation, Brisbane, Queensland, Australia
| | - Adam McKeown
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Smithfield, Queensland, Australia
| | - David A Westcott
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Atherton, Queensland, Australia
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18
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Campbell HA, Beyer HL, Dennis TE, Dwyer RG, Forester JD, Fukuda Y, Lynch C, Hindell MA, Menke N, Morales JM, Richardson C, Rodgers E, Taylor G, Watts ME, Westcott DA. Finding our way: On the sharing and reuse of animal telemetry data in Australasia. Sci Total Environ 2015; 534:79-84. [PMID: 25669144 DOI: 10.1016/j.scitotenv.2015.01.089] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 01/14/2015] [Accepted: 01/25/2015] [Indexed: 06/04/2023]
Abstract
The presence and movements of organisms both reflect and influence the distribution of ecological resources in space and time. The monitoring of animal movement by telemetry devices is being increasingly used to inform management of marine, freshwater and terrestrial ecosystems. Here, we brought together academics, and environmental managers to determine the extent of animal movement research in the Australasian region, and assess the opportunities and challenges in the sharing and reuse of these data. This working group was formed under the Australian Centre for Ecological Analysis and Synthesis (ACEAS), whose overall aim was to facilitate trans-organisational and transdisciplinary synthesis. We discovered that between 2000 and 2012 at least 501 peer-reviewed scientific papers were published that report animal location data collected by telemetry devices from within the Australasian region. Collectively, this involved the capture and electronic tagging of 12 656 animals. The majority of studies were undertaken to address specific management questions; rarely were these data used beyond their original intent. We estimate that approximately half (~500) of all animal telemetry projects undertaken remained unpublished, a similar proportion were not discoverable via online resources, and less than 8.8% of all animals tagged and tracked had their data stored in a discoverable and accessible manner. Animal telemetry data contain a wealth of information about how animals and species interact with each other and the landscapes they inhabit. These data are expensive and difficult to collect and can reduce survivorship of the tagged individuals, which implies an ethical obligation to make the data available to the scientific community. This is the first study to quantify the gap between telemetry devices placed on animals and findings/data published, and presents methods for improvement. Instigation of these strategies will enhance the cost-effectiveness of the research and maximise its impact on the management of natural resources.
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Affiliation(s)
- Hamish A Campbell
- Department of Ecosystem Management, School of Environment and Rural Sciences, University of New England, Armidale, NSW, Australia.
| | - Hawthorne L Beyer
- ARC Centre of Excellence for Environmental Decisions, Centre for Biodiversity & Conservation Science, University of Queensland, Brisbane, QLD, Australia
| | - Todd E Dennis
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Ross G Dwyer
- School of Biological Sciences, University of Queensland, St Lucia, QLD, Australia
| | - James D Forester
- Dept. Fisheries, Wildlife, and Conservation Biology, University of Minnesota, St. Paul, MN, USA
| | - Yusuke Fukuda
- Department of Land Resource Management, PO Box 496, Palmerston, NT, Australia
| | | | | | - Norbert Menke
- Queensland Department of Science, Information, Technoloty, Innovation and the Arts, Brisbane, QLD, Australia
| | - Juan M Morales
- Ecotono, INIBIOMA-CONICET, Universidad Nacional del Comahue, Quintral 1250, 8400 Bariloche, Argentina
| | - Craig Richardson
- Ecological Resources Information Network, Department of the Environment, Canberra, ACT, Australia
| | - Essie Rodgers
- School of Biological Sciences, University of Queensland, St Lucia, QLD, Australia
| | - Graeme Taylor
- Department of Conservation, PO Box 10420, Wellington 6143, New Zealand
| | - Matt E Watts
- ARC Centre of Excellence for Environmental Decisions, Centre for Biodiversity & Conservation Science, University of Queensland, Brisbane, QLD, Australia
| | - David A Westcott
- Commonwealth Scientific and Industrial Research Organisation, PO Box 780, Atherton, QLD, Australia
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19
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Mokany K, Ferrier S, Connolly SR, Dunstan PK, Fulton EA, Harfoot MB, Harwood TD, Richardson AJ, Roxburgh SH, Scharlemann JPW, Tittensor DP, Westcott DA, Wintle BA. Integrating modelling of biodiversity composition and ecosystem function. OIKOS 2015. [DOI: 10.1111/oik.02792] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | - Sean R. Connolly
- School of Marine and Tropical Biology, James Cook University; Townsville QLD Australia
| | | | | | - Michael B. Harfoot
- United Nations Environment Programme World Conservation Monitoring Centre; Cambridge UK
- Computational Ecology and Environmental Science, Microsoft Research; Cambridge UK
| | | | - Anthony J. Richardson
- CSIRO; Brisbane QLD Australia
- Centre for Applications in Natural Resource Mathematics, School of Mathematics and Physics, The Univ. of Queensland; St Lucia QLD Australia
| | | | - Jörn P. W. Scharlemann
- United Nations Environment Programme World Conservation Monitoring Centre; Cambridge UK
- School of Life Sciences, Univ. of Sussex; Brighton UK
| | - Derek P. Tittensor
- United Nations Environment Programme World Conservation Monitoring Centre; Cambridge UK
- Computational Ecology and Environmental Science, Microsoft Research; Cambridge UK
- Dept of Biology; Dalhousie University; Halifax NS Canada
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20
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Kroon FJ, Hook SE, Jones D, Metcalfe S, Henderson B, Smith R, Warne MSJ, Turner RD, McKeown A, Westcott DA. Altered transcription levels of endocrine associated genes in two fisheries species collected from the Great Barrier Reef catchment and lagoon. Mar Environ Res 2015; 104:51-61. [PMID: 25617679 DOI: 10.1016/j.marenvres.2015.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 01/07/2015] [Accepted: 01/12/2015] [Indexed: 06/04/2023]
Abstract
The Great Barrier Reef (GBR) is chronically exposed to agricultural run-off containing pesticides, many of which are known endocrine disrupting chemicals (EDCs). Here, we measure mRNA transcript abundance of two EDC biomarkers in wild populations of barramundi (Lates calcarifer) and coral trout (Plectropomus leopardus and Plectropomus maculatus). Transcription levels of liver vitellogenin (vtg) differed significantly in both species amongst sites with different exposures to agricultural run-off; brain aromatase (cyp19a1b) revealed some differences for barramundi only. Exposure to run-off from sugarcane that contains pesticides is a likely pathway given (i) significant associations between barramundi vtg transcription levels, catchment sugarcane land use, and river pesticide concentrations, and (ii) consistency between patterns of coral trout vtg transcription levels and pesticide distribution in the GBR lagoon. Given the potential consequences of such exposure for reproductive fitness and population dynamics, these results are cause for concern for the sustainability of fisheries resources downstream from agricultural land uses.
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Affiliation(s)
| | - Sharon E Hook
- CSIRO Land and Water, Kirrawee, New South Wales 2232, Australia
| | - Dean Jones
- CSIRO Ecosystem Sciences, Atherton, Queensland 4883, Australia
| | | | - Brent Henderson
- CSIRO Computational Informatics, Acton, Australian Capital Territory 2601, Australia
| | - Rachael Smith
- Queensland Department of Science, Information Technology, Innovation and The Arts, Brisbane, Queensland 4001, Australia
| | - Michael St J Warne
- Queensland Department of Science, Information Technology, Innovation and The Arts, Brisbane, Queensland 4001, Australia
| | - Ryan D Turner
- Queensland Department of Science, Information Technology, Innovation and The Arts, Brisbane, Queensland 4001, Australia
| | - Adam McKeown
- CSIRO Ecosystem Sciences, Smithfield, Queensland 4870, Australia
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21
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Fletcher CS, Westcott DA, Murphy HT, Grice AC, Clarkson JR. Managing breaches of containment and eradication of invasive plant populations. J Appl Ecol 2014; 52:59-68. [PMID: 25678718 PMCID: PMC4312900 DOI: 10.1111/1365-2664.12361] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 09/26/2014] [Indexed: 11/29/2022]
Abstract
Containment can be a viable strategy for managing invasive plants, but it is not always cheaper than eradication. In many cases, converting a failed eradication programme to a containment programme is not economically justified. Despite this, many contemporary invasive plant management strategies invoke containment as a fallback for failed eradication, often without detailing how containment would be implemented.We demonstrate a generalized analysis of the costs of eradication and containment, applicable to any plant invasion for which infestation size, dispersal distance, seed bank lifetime and the economic discount rate are specified. We estimate the costs of adapting eradication and containment in response to six types of breach and calculate under what conditions containment may provide a valid fallback to a breached eradication programme.We provide simple, general formulae and plots that can be applied to any invasion and show that containment will be cheaper than eradication only when the size of the occupied zone exceeds a multiple of the dispersal distance determined by seed bank longevity and the discount rate. Containment becomes proportionally cheaper than eradication for invaders with smaller dispersal distances, longer lived seed banks, or for larger discount rates.Both containment and eradication programmes are at risk of breach. Containment is less exposed to risk from reproduction in the 'occupied zone' and three types of breach that lead to a larger 'occupied zone', but more exposed to one type of breach that leads to a larger 'buffer zone'.For a well-specified eradication programme, only the three types of breach leading to reproduction in or just outside the buffer zone can justify falling back to containment, and only if the expected costs of eradication and containment were comparable before the breach.Synthesis and applications. Weed management plans must apply a consistent definition of containment and provide sufficient implementation detail to assess its feasibility. If the infestation extent, dispersal capacity, seed bank longevity and economic discount rate are specified, the general results presented here can be used to assess whether containment can outperform eradication, and under what conditions it would provide a valid fallback to a breached eradication programme.
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Affiliation(s)
- Cameron S Fletcher
- CSIRO Land & Water Flagship, CSIRO Atherton PO Box 780, Atherton, Qld, 4883, Australia
| | - David A Westcott
- CSIRO Land & Water Flagship, CSIRO Atherton PO Box 780, Atherton, Qld, 4883, Australia
| | - Helen T Murphy
- CSIRO Land & Water Flagship, CSIRO Atherton PO Box 780, Atherton, Qld, 4883, Australia
| | - Anthony C Grice
- CSIRO Land & Water Flagship, Australian Tropical Sciences and Innovation Precinct Private Mail Bag PO, Aitkenvale, Qld, 4814, Australia
| | - John R Clarkson
- Department of National Parks, Recreation, Sport and Racing, Queensland Parks and Wildlife Service PO Box 156, Mareeba, Qld, 4880, Australia
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22
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Mokany K, Prasad S, Westcott DA. Loss of frugivore seed dispersal services under climate change. Nat Commun 2014; 5:3971. [DOI: 10.1038/ncomms4971] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 04/28/2014] [Indexed: 11/09/2022] Open
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Khamcha D, Savini T, Westcott DA, McKeown A, Brockelman WY, Chimchome V, Gale GA. Behavioral and Social Structure Effects on Seed Dispersal Curves of a Forest-Interior Bulbul (Pycnonotidae) in a Tropical Evergreen Forest. Biotropica 2014. [DOI: 10.1111/btp.12100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daphawan Khamcha
- Conservation Ecology Program; School of Bioresources and Technology; King Mongkut's University of Technology Thonburi; 49 Bangkhuntien-Chaithalay Road Thakham, Bangkhuntien Bangkok 10150 Thailand
| | - Tommaso Savini
- Conservation Ecology Program; School of Bioresources and Technology; King Mongkut's University of Technology Thonburi; 49 Bangkhuntien-Chaithalay Road Thakham, Bangkhuntien Bangkok 10150 Thailand
| | - David A. Westcott
- CSIRO Ecosystem Science Atherton; 780 Maunds Road Atherton Qld 4883 Australia
| | - Adam McKeown
- CSIRO Ecosystem Science Atherton; 780 Maunds Road Atherton Qld 4883 Australia
| | - Warren Y. Brockelman
- Ecology Laboratory; Bioresources Technology Unit; 113 Thailand Science Park Paholyothin Road Khlongluang Pathum Thani 12120 Thailand
| | - Vijak Chimchome
- Department of Forest Biology; Faculty of Forestry; Kasetsart University; 50 Ngamwongwan Road Chatuchak Bangkok 10900 Thailand
| | - George A. Gale
- Conservation Ecology Program; School of Bioresources and Technology; King Mongkut's University of Technology Thonburi; 49 Bangkhuntien-Chaithalay Road Thakham, Bangkhuntien Bangkok 10150 Thailand
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Long RL, Gorecki MJ, Renton M, Scott JK, Colville L, Goggin DE, Commander LE, Westcott DA, Cherry H, Finch-Savage WE. The ecophysiology of seed persistence: a mechanistic view of the journey to germination or demise. Biol Rev Camb Philos Soc 2014; 90:31-59. [PMID: 24618017 DOI: 10.1111/brv.12095] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 01/30/2014] [Accepted: 02/04/2014] [Indexed: 11/28/2022]
Abstract
Seed persistence is the survival of seeds in the environment once they have reached maturity. Seed persistence allows a species, population or genotype to survive long after the death of parent plants, thus distributing genetic diversity through time. The ability to predict seed persistence accurately is critical to inform long-term weed management and flora rehabilitation programs, as well as to allow a greater understanding of plant community dynamics. Indeed, each of the 420000 seed-bearing plant species has a unique set of seed characteristics that determine its propensity to develop a persistent soil seed bank. The duration of seed persistence varies among species and populations, and depends on the physical and physiological characteristics of seeds and how they are affected by the biotic and abiotic environment. An integrated understanding of the ecophysiological mechanisms of seed persistence is essential if we are to improve our ability to predict how long seeds can survive in soils, both now and under future climatic conditions. In this review we present an holistic overview of the seed, species, climate, soil, and other site factors that contribute mechanistically to seed persistence, incorporating physiological, biochemical and ecological perspectives. We focus on current knowledge of the seed and species traits that influence seed longevity under ex situ controlled storage conditions, and explore how this inherent longevity is moderated by changeable biotic and abiotic conditions in situ, both before and after seeds are dispersed. We argue that the persistence of a given seed population in any environment depends on its resistance to exiting the seed bank via germination or death, and on its exposure to environmental conditions that are conducive to those fates. By synthesising knowledge of how the environment affects seeds to determine when and how they leave the soil seed bank into a resistance-exposure model, we provide a new framework for developing experimental and modelling approaches to predict how long seeds will persist in a range of environments.
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Affiliation(s)
- Rowena L Long
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia; ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
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Mokany K, Westcott DA, Prasad S, Ford AJ, Metcalfe DJ. Identifying priority areas for conservation and management in diverse tropical forests. PLoS One 2014; 9:e89084. [PMID: 24551222 PMCID: PMC3925232 DOI: 10.1371/journal.pone.0089084] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 01/20/2014] [Indexed: 12/03/2022] Open
Abstract
The high concentration of the world’s species in tropical forests endows these systems with particular importance for retaining global biodiversity, yet it also presents significant challenges for ecology and conservation science. The vast number of rare and yet to be discovered species restricts the applicability of species-level modelling for tropical forests, while the capacity of community classification approaches to identify priorities for conservation and management is also limited. Here we assessed the degree to which macroecological modelling can overcome shortfalls in our knowledge of biodiversity in tropical forests and help identify priority areas for their conservation and management. We used 527 plant community survey plots in the Australian Wet Tropics to generate models and predictions of species richness, compositional dissimilarity, and community composition for all the 4,313 vascular plant species recorded across the region (>1.3 million communities (grid cells)). We then applied these predictions to identify areas of tropical forest likely to contain the greatest concentration of species, rare species, endemic species and primitive angiosperm families. Synthesising these alternative attributes of diversity into a single index of conservation value, we identified two areas within the Australian wet tropics that should be a high priority for future conservation actions: the Atherton Tablelands and Daintree rainforest. Our findings demonstrate the value of macroecological modelling in identifying priority areas for conservation and management actions within highly diverse systems, such as tropical forests.
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Affiliation(s)
- Karel Mokany
- Ecosystem Sciences, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT, Australia
- * E-mail:
| | - David A. Westcott
- Ecosystem Sciences, Commonwealth Scientific and Industrial Research Organisation, Atherton, QLD, Australia
| | - Soumya Prasad
- Centre for Ecological Sciences, Indian Institute of Science, Bangalore, India
| | - Andrew J. Ford
- Ecosystem Sciences, Commonwealth Scientific and Industrial Research Organisation, Atherton, QLD, Australia
| | - Daniel J. Metcalfe
- Ecosystem Sciences, Commonwealth Scientific and Industrial Research Organisation, Dutton Park, QLD, Australia
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Fletcher CS, Westcott DA. Dispersal and the design of effective management strategies for plant invasions: matching scales for success. Ecol Appl 2013; 23:1881-1892. [PMID: 24555314 DOI: 10.1890/12-2059.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Dispersal of propagules makes invasions a fundamentally spatial phenomenon, and to be effective, management actions to control or eradicate invasive species must take this spatial structure into account. While there is a vibrant literature linking detailed dispersal measurements to the rate of invasive spread, and a separate literature focused on incorporating management into invasive models in order to improve the control of weeds, there are relatively fewer manuscripts incorporating state-of-the-art dispersal modeling and management modeling together to provide on-ground recommendations for structuring effective management. In this paper, we perform a generalized analysis of a spatially explicit, individual-based simulation model of invasion management with empirically determined dispersal processes, illustrated with the example of Miconia calvescens in the Australian Wet Tropics rain forest, to explore how matching the spatial scale of management to the spatial scale of the dispersal processes underpinning invasion influences the success of management. We find that management strategies designed to maximize the number of weeds removed from the management region, either in the first year of management or over longer periods, provide a poor estimate of the spatial scale of management that maximizes the probability of eradication. We show that achieving a goal of certainty of eradication requires exceeding a minimal spatial scale of management and total management resourcing. We generalize these results to examine how the spatial scale of dispersal drives the spatial scale of effective management strategies. These results show that to be effective, management of dispersal-driven invasions must occur at spatial scales determined by the scale of dispersal processes, and resourced accordingly. It illustrates how those scales might be calculated for a specific case for which detailed dispersal data are available and generalizes the result to highlight how dispersal scale drives the scale of effective management. The results highlight the importance of understanding the ecological drivers of invasion to structure effective management.
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Affiliation(s)
- Cameron S Fletcher
- CSIRO Ecosystem Sciences, P.O. Box 780, Atherton, Queensland 4883, Australia.
| | - David A Westcott
- CSIRO Ecosystem Sciences, P.O. Box 780, Atherton, Queensland 4883, Australia
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Buettner PG, Westcott DA, Maclean J, Brown L, McKeown A, Johnson A, Wilson K, Blair D, Luly J, Skerratt L, Muller R, Speare R. Tick paralysis in spectacled flying-foxes (Pteropus conspicillatus) in North Queensland, Australia: impact of a ground-dwelling ectoparasite finding an arboreal host. PLoS One 2013; 8:e73078. [PMID: 24066028 PMCID: PMC3774714 DOI: 10.1371/journal.pone.0073078] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 07/17/2013] [Indexed: 11/19/2022] Open
Abstract
When a parasite finds a new wildlife host, impacts can be significant. In the late 1980s populations of Spectacled Flying-foxes (SFF) (Pteropus conspicillatus), a species confined, in Australia, to north Queensland became infected by paralysis tick (Ixodes holocyclus), resulting in mortality. This Pteropus-tick relationship was new to Australia. Curiously, the relationship was confined to several camps on the Atherton Tableland, north Queensland. It was hypothesised that an introduced plant, wild tobacco (Solanum mauritianum), had facilitated this new host-tick interaction. This study quantifies the impact of tick paralysis on SFF and investigates the relationship with climate. Retrospective analysis was carried out on records from the Tolga Bat Hospital for 1998–2010. Juvenile mortality rates were correlated to climate data using vector auto-regression. Mortality rates due to tick paralysis ranged between 11.6 per 10,000 bats in 2003 and 102.5 in 2009; more female than male adult bats were affected. Juvenile mortality rates were negatively correlated with the total rainfall in January to March and July to September of the same year while a positive correlation of these quarterly total rainfalls existed with the total population. All tick affected camps of SFF were located in the 80% core range of S. mauritianum. This initial analysis justifies further exploration of how an exotic plant might alter the relationship between a formerly ground-dwelling parasite and an arboreal host.
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Affiliation(s)
- Petra G. Buettner
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Australia
- Tropical Health Solutions Pty Ltd, Idalia, Townsville, Australia
- * E-mail:
| | - David A. Westcott
- CSIRO Ecosystem Sciences, Atherton, Queensland, Australia
- Centre for Tropical Environmental and Sustainability Science, School of Earth and Environmental Sciences and School of Marine and Tropical Biology, James Cook University, Cairns, Australia
| | | | - Lawrence Brown
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Australia
| | - Adam McKeown
- CSIRO Ecosystem Sciences, Atherton, Queensland, Australia
| | | | - Karen Wilson
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Australia
| | - David Blair
- School of Marine and Tropical Biology, James Cook University, Townsville, Australia
| | - Jonathan Luly
- School of Earth and Environmental Sciences, James Cook University, Townsville, Australia
| | - Lee Skerratt
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Australia
| | - Reinhold Muller
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Australia
- Tropical Health Solutions Pty Ltd, Idalia, Townsville, Australia
| | - Richard Speare
- School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, Australia
- Tropical Health Solutions Pty Ltd, Idalia, Townsville, Australia
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Corlett RT, Westcott DA. Will plant movements keep up with climate change? Trends Ecol Evol 2013; 28:482-8. [PMID: 23721732 DOI: 10.1016/j.tree.2013.04.003] [Citation(s) in RCA: 288] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Revised: 04/16/2013] [Accepted: 04/25/2013] [Indexed: 11/16/2022]
Abstract
In the face of anthropogenic climate change, species must acclimate, adapt, move, or die. Although some species are moving already, their ability to keep up with the faster changes expected in the future is unclear. 'Migration lag' is a particular concern with plants, because it could threaten both biodiversity and carbon storage. Plant movements are not realistically represented in models currently used to predict future vegetation and carbon-cycle feedbacks, so there is an urgent need to understand how much of a problem failure to track climate change is likely to be. Therefore, in this review, we compare how fast plants need to move with how fast they can move; that is, the velocity of climate change with the velocity of plant movement.
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Affiliation(s)
- Richard T Corlett
- Center for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla, Yunnan 666303, China.
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Rader R, Edwards W, Westcott DA, Cunningham SA, Howlett BG. Diurnal effectiveness of pollination by bees and flies in agricultural Brassica rapa: Implications for ecosystem resilience. Basic Appl Ecol 2013. [DOI: 10.1016/j.baae.2012.10.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Westcott DA, Kroon FJ, Sheppard AW. Policy: Biodiversity needs a scientific approach. Nature 2012; 490:37. [PMID: 23038454 DOI: 10.1038/490037a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Wurster CM, Robertson J, Westcott DA, Dryden B, Zazzo A, Bird MI. Utilization of sugarcane habitat by feral pig (Sus scrofa) in northern tropical Queensland: evidence from the stable isotope composition of hair. PLoS One 2012; 7:e43538. [PMID: 22957029 PMCID: PMC3434169 DOI: 10.1371/journal.pone.0043538] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 07/23/2012] [Indexed: 11/19/2022] Open
Abstract
Feral pigs (Sus scrofa) are an invasive species that disrupt ecosystem functioning throughout their introduced range. In tropical environments, feral pigs are associated with predation and displacement of endangered species, modification of habitat, and act as a vector for the spread of exotic vegetation and disease. Across many parts of their introduced range, the diet of feral pigs is poorly known. Although the remote location and difficult terrain of far north Queensland makes observing feral pig behavior difficult, feral pigs are perceived to seek refuge in World Heritage tropical rainforests and seasonally ‘crop raid’ into lowland sugarcane crops. Thus, identifying how feral pigs are using different components of the landscape is important to the design of management strategies. We used the stable isotope composition of captured feral pigs to determine the extent of rainforest and sugarcane habitat usage. Recently grown hair (basal hair) from feral pigs captured in remote rainforest indicated pigs met their dietary needs solely within this habitat. Stable carbon and nitrogen isotope values of basal hair from feral pigs captured near sugarcane plantations were more variable, with some individuals estimated to consume over 85% of their diet within a sugarcane habitat, while a few consumed as much as 90% of their diet from adjacent forested environments. We estimated whether feral pigs switch habitats by sequentially sampling δ13C and δ15N values of long tail hair from a subset of seven captured animals, and demonstrate that four of these individuals moved between habitats. Our results indicate that feral pigs utilize both sugarcane and forest habitats, and can switch between these resources.
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Affiliation(s)
- Christopher M Wurster
- School of Earth and Environmental Sciences and Centre for Tropical Environmental and Sustainability Science, James Cook University, Cairns, Queensland, Australia.
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Campbell HA, Dwyer RG, Fitzgibbons S, Klein CJ, Lauridsen G, McKeown A, Olsson A, Sullivan S, Watts ME, Westcott DA. Prioritising the protection of habitat utilised by southern cassowaries Casuarius casuarius johnsonii. ENDANGER SPECIES RES 2012. [DOI: 10.3354/esr00397] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Abstract
Monitoring of population trends is a critical component of conservation management, and development of practical methods remains a priority, particularly for species that challenge more standard approaches. We used field-parameterized simulation models to examine the effects of different errors on monitoring power and compared alternative methods used with two species of threatened pteropodids (flying-foxes), Pteropus conspicillatus and P. poliocephalus, whose mobility violates assumptions of closure on short and long timescales. The influence of three errors on time to 80% statistical power was assessed using a Monte Carlo approach. The errors were: (1) failure to count all animals at a roost, (2) errors associated with enumeration, and (3) variability in the proportion of the population counted due to the movement of individuals between roosts. Even with perfect accuracy and precision for these errors only marginal improvements in power accrued (-1%), with one exception. Improving certainty in the proportion of the population being counted reduced time to detection of a decline by over 6 yr (43%) for fly-out counts and almost 10 yr (71%) for walk-through counts. This error derives from the movement of animals between known and unknown roost sites, violating assumptions of population closure, and because it applies to the entire population, it dominates all other sources of error. Similar errors will accrue in monitoring of a wide variety of highly mobile species and will also result from population redistribution under climate change. The greatest improvements in monitoring performance of highly mobile species accrue through an improved understanding of the proportion of the population being counted, and consequently monitoring of such species must be done at the scale of the species or population range, not at the local level.
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Affiliation(s)
- David A Westcott
- CSIRO Ecosystem Sciences, P.O. Box 780, Atherton, Queensland 4883, Australia.
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Westcott DA, Fletcher CS. Biological invasions and the study of vertebrate dispersal of plants: Opportunities and integration. Acta Oecologica 2011. [DOI: 10.1016/j.actao.2011.04.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Hardesty BD, Metcalfe SS, Westcott DA. Persistence and spread in a new landscape: Dispersal ecology and genetics of Miconia invasions in Australia. Acta Oecologica 2011. [DOI: 10.1016/j.actao.2011.06.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Rader R, Howlett BG, Cunningham SA, Westcott DA, Edwards W. Spatial and temporal variation in pollinator effectiveness: do unmanaged insects provide consistent pollination services to mass flowering crops? J Appl Ecol 2011. [DOI: 10.1111/j.1365-2664.2011.02066.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Rader R, Edwards W, Westcott DA, Cunningham SA, Howlett BG. Pollen transport differs among bees and flies in a human-modified landscape. DIVERS DISTRIB 2011. [DOI: 10.1111/j.1472-4642.2011.00757.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Rader R, Howlett BG, Cunningham SA, Westcott DA, Newstrom-Lloyd LE, Walker MK, Teulon DA, Edwards W. Alternative pollinator taxa are equally efficient but not as effective as the honeybee in a mass flowering crop. J Appl Ecol 2009. [DOI: 10.1111/j.1365-2664.2009.01700.x] [Citation(s) in RCA: 191] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kroon FJ, Munday PL, Westcott DA. Equivalent whole-body concentrations of 11-ketotestosterone in female and male coral goby Gobiodon erythrospilus, a bidirectional sex-changing fish. J Fish Biol 2009; 75:685-692. [PMID: 20738565 DOI: 10.1111/j.1095-8649.2009.02274.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The relationship between whole-body concentrations of 11-ketotestosterone (11-KT) and sexual function was examined in the coral goby Gobiodon erythrospilus, a bi-directional sex-changing fish. 11-KT occurred in both female and male G. erythrospilus, but levels were not always higher in males than in females within heterosexual pairs, and were not related to the stage of gonadal development of individual fish. These results suggest that comparable 11-KT levels in both sexes may allow serial adult sex change to take place in bi-directional sex-changing species, such as Gobiodon spp.
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Affiliation(s)
- F J Kroon
- CSIRO Sustainable Ecosystems, P. O. Box 780, Atherton, QLD 4883, Australia.
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Bradford MG, Dennis AJ, Westcott DA. Diet and Dietary Preferences of the Southern Cassowary (Casuarius casuarius) in North Queensland, Australia. Biotropica 2008. [DOI: 10.1111/j.1744-7429.2007.00372.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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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. Wildl Res 2008. [DOI: 10.1071/wr07127] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [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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Koetz AH, Westcott DA, Congdon BC. Geographical variation in song frequency and structure: the effects of vicariant isolation, habitat type and body size. Anim Behav 2007. [DOI: 10.1016/j.anbehav.2007.03.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Westcott DA, Setter M, Bradford MG, McKeown A, Setter S. Cassowary dispersal of the invasive pond apple in a tropical rainforest: the contribution of subordinate dispersal modes in invasion. DIVERS DISTRIB 2007. [DOI: 10.1111/j.1472-4642.2007.00416.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Affiliation(s)
- John A. Endler
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California 93106
- Department of Zoology and Tropical Ecology, James Cook University, Townsville, Queensland 4811, Australia
| | - David A. Westcott
- CSIRO Sustainable Ecosystems and the Rainforest Cooperative Research Centre, P.O. Box 780, Atherton, Queensland 4883, Australia
| | - Joah R. Madden
- Department of Zoology, Cambridge University, Cambridge CB2 3EJ, United Kingdom
| | - Tim Robson
- Department of Zoology and Entomology, University of Queensland, St. Lucia, Queensland 4072, Australia
- Statutory Planning Department, Gold Coast City Council, P.O. Box 5042, Gold Coast Mail Centre, Queensland 9729, Australia
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Parsons JG, Cairns A, Johnson CN, Robson SKA, Shilton LA, Westcott DA. Bryophyte dispersal by flying foxes: a novel discovery. Oecologia 2007; 152:112-4. [PMID: 17216209 DOI: 10.1007/s00442-006-0639-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2006] [Accepted: 12/04/2006] [Indexed: 10/23/2022]
Abstract
This research provides the first evidence of dispersal of bryophytes and associated microorganisms through ingestion by a highly mobile vertebrate vector, the spectacled flying fox (Pteropus conspicillatus). Bryophyte fragments were found in faeces collected at four P. conspicillatus' camps in the Wet Tropics bioregion, northeastern Australia. These fragments were viable when grown in culture; live invertebrates and other organisms were also present. Our study has significantly increased understanding of the role of flying foxes as dispersal vectors in tropical forests.
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Affiliation(s)
- J G Parsons
- School of Marine and Tropical Biology, James Cook University, Townsville, QLD, Australia.
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Dennis AJ, Westcott DA. Reducing complexity when studying seed dispersal at community scales: a functional classification of vertebrate seed dispersers in tropical forests. Oecologia 2006; 149:620-34. [PMID: 16858588 DOI: 10.1007/s00442-006-0475-3] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2006] [Accepted: 05/24/2006] [Indexed: 10/24/2022]
Abstract
The process of seed dispersal has a profound effect on vegetation structure and diversity in tropical forests. However, our understanding of the process and our ability to predict its outcomes at a community scale are limited by the frequently large number of interactions associated with it. Here, we outline an approach to dealing with this complexity that reduces the number of unique interactions considered by classifying the participants according to their functional similarity. We derived a classification of dispersers based on the nature of the dispersal service they provide to plants. We described the quantities of fruit handled, the quality of handling and the diversity of plants to which the service is provided. We used ten broad disperser traits to group 26 detailed measures for each disperser. We then applied this approach to vertebrate dispersers in Australia's tropical forests. Using this we also develop a classification that may be more generally applicable. For each disperser, data relating to each trait was obtained either from the field or published literature. First, we identified dispersers whose service outcomes were so distinct that statistical analysis was not required and assigned them to functional groups. The remaining dispersers were assigned to functional groups using cluster analysis. The combined processes created 15 functional groups from 65 vertebrate dispersers in Australian tropical forests. Our approach--grouping dispersers on the basis of the type of dispersal service provided and the fruit types it is provided to--represents a means of reducing the complexity encountered in tropical seed dispersal systems and could be effectively applied in community level studies. It also represents a useful tool for exploring changes in dispersal services when the distribution and abundance of animal populations change due to human impacts.
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Affiliation(s)
- Andrew J Dennis
- CSIRO Sustainable Ecosystems and the Rainforest CRC, P.O. Box 780, Atherton, QLD, 4883, Australia.
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Endler JA, Westcott DA, Madden JR, Robson T. Animal visual systems and the evolution of color patterns: sensory processing illuminates signal evolution. Evolution 2006; 59:1795-818. [PMID: 16329248 DOI: 10.1554/04-669.1] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Animal color pattern phenotypes evolve rapidly. What influences their evolution? Because color patterns are used in communication, selection for signal efficacy, relative to the intended receiver's visual system, may explain and predict the direction of evolution. We investigated this in bowerbirds, whose color patterns consist of plumage, bower structure, and ornaments and whose visual displays are presented under predictable visual conditions. We used data on avian vision, environmental conditions, color pattern properties, and an estimate of the bowerbird phylogeny to test hypotheses about evolutionary effects of visual processing. Different components of the color pattern evolve differently. Plumage sexual dimorphism increased and then decreased, while overall (plumage plus bower) visual contrast increased. The use of bowers allows relative crypsis of the bird but increased efficacy of the signal as a whole. Ornaments do not elaborate existing plumage features but instead are innovations (new color schemes) that increase signal efficacy. Isolation between species could be facilitated by plumage but not ornaments, because we observed character displacement only in plumage. Bowerbird color pattern evolution is at least partially predictable from the function of the visual system and from knowledge of different functions of different components of the color patterns. This provides clues to how more constrained visual signaling systems may evolve.
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Affiliation(s)
- John A Endler
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara 93106, USA.
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Parsons JG, Cairns A, Johnson CN, Robson SKA, Shilton LA, Westcott DA. Dietary variation in spectacled flying foxes (Pteropus conspicillatus) of the Australian Wet Tropics. AUST J ZOOL 2006. [DOI: 10.1071/zo06092] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The diet of Pteropus conspicillatus, a large flying fox, was examined by collecting faeces in traps beneath daytime roost trees in four geographically distinct camps in the Wet Tropics bioregion of North-eastern Queensland, Australia. Faecal analyses revealed that P. conspicillatus utilise a broad variety of plant resources from a variety of habitats. Seed and pulp from figs (Ficus spp., Moraceae) and pollen from the family Myrtaceae were most frequently represented in the faeces from a range of both wet sclerophyll and rainforest habitats. The dietary composition of P. conspicillatus at individual camps could not be predicted by the habitats located within a typical foraging distance of each camp (20 km), and although consistent dietary changes were seen across all camps over time, each camp had a unique dietary signature indicative of feeding on a distinct subset of available vegetation. The unique diet of each camp and the variety of dietary items consumed suggest that camps may need to be managed on an individual camp-specific basis, and that P. conspicillatus are utilising a broader range of resources than would be expected if the species was a strict ‘rainforest-fruit specialist’.
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Westcott DA, Bentrupperbäumer J, Bradford MG, McKeown A. Incorporating patterns of disperser behaviour into models of seed dispersal and its effects on estimated dispersal curves. Oecologia 2005; 146:57-67. [PMID: 16032438 DOI: 10.1007/s00442-005-0178-1] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2004] [Accepted: 06/01/2005] [Indexed: 10/25/2022]
Abstract
The processes determining where seeds fall relative to their parent plant influence the spatial structure and dynamics of plant populations and communities. For animal dispersed species the factors influencing seed shadows are poorly understood. In this paper we test the hypothesis that the daily temporal distribution of disperser behaviours, for example, foraging and movement, influences dispersal outcomes, in particular the shape and scale of dispersal curves. To do this, we describe frugivory and the dispersal curves produced by the southern cassowary, Casuarius casuarius, the only large-bodied disperser in Australia's rainforests. We found C. casuarius consumed fruits of 238 species and of all fleshy-fruit types. In feeding trials, seeds of 11 species were retained on average for 309 min (+/-256 SD). Sampling radio-telemetry data randomly, that is, assuming foraging occurs at random times during the day, gives an estimated average dispersal distance of 239 m (+/-207 SD) for seeds consumed by C. casuarius. Approximately 4% of seeds were dispersed further than 1,000 m. However, observation of wild birds indicated that foraging and movement occur more frequently early and late in the day. Seeds consumed early in the day were estimated to receive dispersal distances 1.4 times the 'random' average estimate, while afternoon consumed seeds received estimated mean dispersal distances of 0.46 times the 'random' estimate. Sampling movement data according to the daily distribution of C. casuarius foraging gives an estimated mean dispersal distance of 337 m (+/-194 SD). Most animals' behaviour has a non-random temporal distribution. Consequently such effects should be common and need to be incorporated into seed shadow estimation. Our results point to dispersal curves being an emergent property of the plant-disperser interaction rather than being a property of a plant or species.
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Affiliation(s)
- David A Westcott
- CSIRO Sustainable Ecosystems & the Rainforest CRC, PO Box 780, Atherton Q, 4883, Australia.
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