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Vanderduys EP, Caley P, McKeown A, Martin JM, Pavey C, Westcott D. Population trends in the vulnerable Grey-headed flying-fox, Pteropus poliocephalus; results from a long-term, range-wide study. PLoS One 2024; 19:e0298530. [PMID: 38512935 PMCID: PMC10956843 DOI: 10.1371/journal.pone.0298530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Accepted: 01/25/2024] [Indexed: 03/23/2024] Open
Abstract
Monitoring is necessary for the management of any threatened species if its predicament and status are to improve. Monitoring establishes baseline data for tracking trends in distribution and abundance and is a key tool for informing threatened species management. Across much of the Old World, bats in the genus Pteropus (Pteropodidae, Chiroptera) face significant threats from habitat loss, conflict with humans, and hunting. Despite conflict with humans and their threatened status, few Pteropus are being monitored. Often, this is because of difficulties associated with their high mobility, large and easily disturbed aggregations, and their use of unknown or remote habitat. Here we describe 10 years of results from the National Flying-fox Monitoring Program (NFFMP) for the grey-headed flying-fox, (Pteropus poliocephalus) in Australia. Range-wide quarterly surveys were conducted over a three-day period since November 2012 using standardized methods appropriate to conditions encountered at each roost. For our analysis of the population and its trend, we used a state-space model to account for the ecology of the grey-headed flying-fox and the errors associated with the surveying process. Despite the general perception that the species is in decline, our raw data and the modelled population trend suggest the grey-headed flying-fox population has remained stable during the NFFMP period, with the range also stable. These results indicate that the species' extreme mobility and broad diet bestow it with a high level of resilience to various disturbance events. Long-term, range-wide studies such as this one, are crucial for understanding relatively long-lived and highly nomadic species such as the grey-headed flying-fox. The outcomes of this study highlight the need for such systematic population monitoring of all threatened Pteropus species.
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Affiliation(s)
- Eric Peter Vanderduys
- Environment, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Brisbane, Queensland, Australia
| | - Peter Caley
- Data61, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Canberra, Australian Capital Territory, Australia
| | - Adam McKeown
- Environment, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Adelaide, South Australia, Australia
| | - John M. Martin
- Wildlife Services, Ecosure, Brisbane, Queensland, Australia
| | - Chris Pavey
- Environment, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Brisbane, Queensland, Australia
| | - David Westcott
- Environment, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Atherton, Queensland, Australia
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2
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Erickson E, Grozinger CM, Patch HM. Measuring Plant Attractiveness to Pollinators: Methods and Considerations. JOURNAL OF ECONOMIC ENTOMOLOGY 2022; 115:1571-1582. [PMID: 35640204 DOI: 10.1093/jee/toac066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Indexed: 06/15/2023]
Abstract
Global pollinator declines have fostered increased public interest in creating pollinator-friendly gardens in human-managed landscapes. Indeed, studies on urban pollinator communities suggest that flower-rich greenspaces can serve as promising sites for conservation. Ornamental flowers, which are readily available at most commercial garden centers, are ubiquitous in these landscapes. These varieties are often non-native and highly bred, and their utility to pollinators is complex. In this study, we used observational data and citizen science to develop a methods framework that will assist stakeholders in the floriculture industry to incorporate metrics of pollinator health into existing breeding and evaluation protocols. The results of this study support how plant attractiveness to pollinators is often dependent on variables such as climate and plant phenology, which should be considered when developing an assessment tool. Furthermore, we found that some cultivars were consistently attractive across all observations while for other cultivars, pollinator visitation was apparently conditional. We determine using multiple statistical tests that 10 min is a sufficient length of time for observation of most plant types to broadly estimate three measures of plant attractiveness: visitor abundance, primary visitors attracted, and cultivar rank attractiveness, without sacrificing efficiency or accuracy. Additionally, we demonstrate that properly trained non-expert observers can collect accurate observational data, and our results suggest that protocols may be designed to maximize consistency across diverse data collectors.
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Affiliation(s)
- E Erickson
- Department of Biology, Tufts University, 200 Boston Ave, 4700 Medford, MA 02155, USA
| | - C M Grozinger
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life Sciences, Pennsylvania State University, 501 ASI Building University Park, PA 16802, USA
| | - H M Patch
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life Sciences, Pennsylvania State University, 501 ASI Building University Park, PA 16802, USA
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Lunn TJ, Eby P, Brooks R, McCallum H, Plowright RK, Kessler MK, Peel AJ. Conventional wisdom on roosting behavior of Australian flying-foxes-A critical review, and evaluation using new data. Ecol Evol 2021; 11:13532-13558. [PMID: 34646488 PMCID: PMC8495814 DOI: 10.1002/ece3.8079] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 08/14/2021] [Accepted: 08/18/2021] [Indexed: 11/24/2022] Open
Abstract
Fruit bats (Family: Pteropodidae) are animals of great ecological and economic importance, yet their populations are threatened by ongoing habitat loss and human persecution. A lack of ecological knowledge for the vast majority of Pteropodid species presents additional challenges for their conservation and management.In Australia, populations of flying-fox species (Genus: Pteropus) are declining and management approaches are highly contentious. Australian flying-fox roosts are exposed to management regimes involving habitat modification, through human-wildlife conflict management policies, or vegetation restoration programs. Details on the fine-scale roosting ecology of flying-foxes are not sufficiently known to provide evidence-based guidance for these regimes, and the impact on flying-foxes of these habitat modifications is poorly understood.We seek to identify and test commonly held understandings about the roosting ecology of Australian flying-foxes to inform practical recommendations and guide and refine management practices at flying-fox roosts.We identify 31 statements relevant to understanding of flying-fox roosting structure and synthesize these in the context of existing literature. We then contribute a contemporary, fine-scale dataset on within-roost structure to further evaluate 11 of these statements. The new dataset encompasses 13-monthly repeat measures from 2,522 spatially referenced roost trees across eight sites in southeastern Queensland and northeastern New South Wales.We show evidence of sympatry and indirect competition between species, including spatial segregation of black and grey-headed flying-foxes within roosts and seasonal displacement of both species by little red flying-foxes. We demonstrate roost-specific annual trends in occupancy and abundance and provide updated demographic information including the spatial and temporal distributions of males and females within roosts.Insights from our systematic and quantitative study will be important to guide evidence-based recommendations on restoration and management and will be crucial for the implementation of priority recovery actions for the preservation of these species in the future.
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Affiliation(s)
- Tamika J. Lunn
- Centre for Planetary Health and Food SecurityGriffith UniversityNathanQLDAustralia
| | - Peggy Eby
- Centre for Planetary Health and Food SecurityGriffith UniversityNathanQLDAustralia
- School of Biological Earth and Environmental SciencesUniversity of New South WalesSydneyNSWAustralia
| | - Remy Brooks
- Centre for Planetary Health and Food SecurityGriffith UniversityNathanQLDAustralia
| | - Hamish McCallum
- Centre for Planetary Health and Food SecurityGriffith UniversityNathanQLDAustralia
| | - Raina K. Plowright
- Department of Microbiology and ImmunologyMontana State UniversityBozemanMTUSA
| | | | - Alison J. Peel
- Centre for Planetary Health and Food SecurityGriffith UniversityNathanQLDAustralia
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4
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Oedin M, Brescia F, Boissenin M, Vidal E, Cassan JJ, Hurlin JC, Millon A. Monitoring hunted species of cultural significance: Estimates of trends, population sizes and harvesting rates of flying-fox (Pteropus sp.) in New Caledonia. PLoS One 2019; 14:e0224466. [PMID: 31891573 PMCID: PMC6938311 DOI: 10.1371/journal.pone.0224466] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 10/14/2019] [Indexed: 11/18/2022] Open
Abstract
Assessing population trends and their underlying factors is critical to propose efficient conservation actions. This assessment can be particularly challenging when dealing with highly mobile, shy and nocturnal animals such as flying-foxes. Here we investigated the dynamics of hunted populations of Pteropus ornatus and P. tonganus in the Northern Province of New Caledonia. First, an ethno-ecological survey involving 219 local experts identified 494 flying-fox roosts. Current status was assessed for 379 of them, among which 125 were no longer occupied, representing a loss of 33% over ca. 40 years. Second, species-specific counts conducted at 35 roosts, and a sample of animals killed by hunters, revealed that the endemic species, P. ornatus, was dominant (68.5%). Between 2010 and 2016, 30 roosts were counted annually during the pre-parturition period. Roosts size averaged 1,425 ± 2,151 individuals (N = 180 counts) and showed high among-year variations (roost-specific CV = 37-162%). If we recorded significant inter-annual variation, we did not detect a significant decline over the 7-yr period, although one roost went possibly extinct. Population size of the two species combined was estimated at 338,000-859,000 individuals distributed over ca. 400 roosts in the Northern Province. Flying-foxes are popular game species and constitute traditional food for all communities of New Caledonia. Annual bags derived from a food survey allowed us to estimate harvesting rates at 5-14%. Such a level of harvesting for species with a 'slow' demography, the occurrence of poaching and illegal trade, suggest the current species use might not be sustainable and further investigations are critically needed.
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Affiliation(s)
- Malik Oedin
- Institut Agronomique Néo-Calédonien (IAC), Equipe ARBOREAL (AgricultuRe BiOdiveRsité Et vALorisation) BP, Païta, Nouvelle-Calédonie
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Aix Marseille Université, CNRS, IRD, Avignon Université, Centre IRD Nouméa, Nouvelle-Calédonie
| | - Fabrice Brescia
- Institut Agronomique Néo-Calédonien (IAC), Equipe ARBOREAL (AgricultuRe BiOdiveRsité Et vALorisation) BP, Païta, Nouvelle-Calédonie
| | - Mélanie Boissenin
- Institut Agronomique Néo-Calédonien (IAC), Equipe ARBOREAL (AgricultuRe BiOdiveRsité Et vALorisation) BP, Païta, Nouvelle-Calédonie
| | - Eric Vidal
- Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Aix Marseille Université, CNRS, IRD, Avignon Université, Centre IRD Nouméa, Nouvelle-Calédonie
- UMR Entropie (IRD, Université de La Réunion, CNRS), Labex-Corail, Institut de Recherche pour le Développement (IRD), Nouvelle-Calédonie
| | - Jean-Jérôme Cassan
- Province Nord, Direction du Développement Economique et de l’Environnement, Service impact environnemental et conservation (DDEE), Service impact environnemental & conservation, Koné, Nouvelle-Calédonie
| | - Jean-Claude Hurlin
- Institut Agronomique Néo-Calédonien (IAC), Equipe ARBOREAL (AgricultuRe BiOdiveRsité Et vALorisation) BP, Païta, Nouvelle-Calédonie
| | - Alexandre Millon
- Aix Marseille Université, CNRS, IRD, Avignon Université, Institut Méditerranéen de Biodiversité et d’Ecologie marine et continentale (IMBE), Technopôle Arbois-Méditerranée, Aix-en-Provence, France
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5
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Using weather radar to monitor the number, timing and directions of flying-foxes emerging from their roosts. Sci Rep 2019; 9:10222. [PMID: 31308411 PMCID: PMC6629676 DOI: 10.1038/s41598-019-46549-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 06/27/2019] [Indexed: 11/08/2022] Open
Abstract
Knowledge of species' population trends is crucial when planning for conservation and management; however, this information can be difficult to obtain for extremely mobile species such as flying-foxes (Pteropus spp.; Chiroptera, Pteropodidae). In mainland Australia, flying-foxes are of particular management concern due their involvement in human-wildlife conflict, and their role as vectors of zoonotic diseases; and two species, the grey-headed flying-fox (Pteropus poliocephalus) and the spectacled flying-fox (P. conspicillatus), are currently threatened with extinction. Here we demonstrate that archival weather radar data over a period of ten years can be used to monitor a large colony of grey-headed flying-foxes near Melbourne. We show that radar estimates of colony size closely match those derived from traditional counting methods. Moreover, we show that radar data can be used to determine the timing and departure direction of flying-foxes emerging from the roost. Finally, we show that radar observations of flying-foxes can be used to identify signals of important ecological events, such as mass flowering and extreme heat events, and can inform human activities, e.g. the safe operation of airports and windfarms. As such, radar represents an extremely promising tool for the conservation and management of vulnerable flying-fox populations and for managing human interactions with these ecologically-important mammals.
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Peel AJ, Wood JLN, Baker KS, Breed AC, Carvalho AD, Fernández-Loras A, Gabrieli HS, Gembu GC, Kakengi VA, Kaliba PM, Kityo RM, Lembo T, Mba FE, Ramos D, Rodriguez-Prieto I, Suu-Ire R, Cunningham AA, Hayman DTS. How Does Africa's Most Hunted Bat Vary Across the Continent? Population Traits of the Straw-Coloured Fruit Bat (Eidolon helvum) and Its Interactions with Humans. ACTA CHIROPTEROLOGICA 2017. [DOI: 10.3161/15081109acc2017.19.1.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Alison J. Peel
- Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, United Kingdom
| | - James L. N. Wood
- Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, United Kingdom
| | - Kate S. Baker
- Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, United Kingdom
| | - Andrew C. Breed
- Animal and Plant Health Agency (APHA), Addlestone, Surrey, KT15 3NB, United Kingdom
| | - Arlindo De Carvalho
- Direção Geral de Ambiente, Avenida Kwame Krhuma-Caixa Postal 1023, São Tomé, São Tomé e Príncipe
| | - Andrés Fernández-Loras
- Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, United Kingdom
| | - Harrison Sadiki Gabrieli
- Tanzania Veterinary Laboratory Agency (TVLA), Ministry of Livestock Development and Fisheries (MLDF), P.O. Box 1026, Tanga, Tanzania
| | - Guy-Crispin Gembu
- Faculté des Sciences, Université de Kisangani, Kisangani, République Démocratique du Congo
| | | | | | - Robert M. Kityo
- College of Natural Sciences, School of BioSciences, Department of Biological Sciences. Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Tiziana Lembo
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Graham Kerr Building, Glasgow, G12 8QQ, Scotland
| | - Fidel Esono Mba
- Instituto Nacional de Desarrollo Forestal y Manejo del Sistema de Áreas Protegidas (INDEFOR-AP), Calle Jesús Bakale S/N, Bata, Equatorial Guinea
| | - Daniel Ramos
- Parque Natural do Príncipe, Avenida Amilcar Cabral, Cidade de Santo António, Ilha do Príncipe, São Tomé e Príncipe
| | - Iñaki Rodriguez-Prieto
- Department of Evolutionary Ecology, Museo Nacional de Ciencias Naturales, CSIC 28006 Madrid, Spain
| | | | - Andrew A. Cunningham
- Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, United Kingdom
| | - David T. S. Hayman
- Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, United Kingdom
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7
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Hendra Virus Infection Dynamics in the Grey-Headed Flying Fox (Pteropus poliocephalus) at the Southern-Most Extent of Its Range: Further Evidence This Species Does Not Readily Transmit the Virus to Horses. PLoS One 2016; 11:e0155252. [PMID: 27304985 PMCID: PMC4909227 DOI: 10.1371/journal.pone.0155252] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 04/26/2016] [Indexed: 12/14/2022] Open
Abstract
Hendra virus (HeV) is an important emergent virus in Australia known to infect horses and humans in certain regions of the east coast. Whilst pteropid bats (“flying foxes”) are considered the natural reservoir of HeV, which of the four mainland species is the principal reservoir has been a source of ongoing debate, particularly as shared roosting is common. To help resolve this, we sampled a colony consisting of just one of these species, the grey-headed flying fox, (Pteropus poliocephalus), at the southernmost extent of its range. Using the pooled urine sampling technique at approximately weekly intervals over a two year period, we determined the prevalence of HeV and related paramyxoviruses using a novel multiplex (Luminex) platform. Whilst all the pooled urine samples were negative for HeV nucleic acid, we successfully identified four other paramyxoviruses, including Cedar virus; a henipavirus closely related to HeV. Collection of serum from individually caught bats from the colony showed that antibodies to HeV, as estimated by a serological Luminex assay, were present in between 14.6% and 44.5% of animals. The wide range of the estimate reflects uncertainties in interpreting intermediate results. Interpreting the study in the context of HeV studies from states to the north, we add support for an arising consensus that it is the black flying fox and not the grey-headed flying fox that is the principal source of HeV in spillover events to horses.
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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] [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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9
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Westcott DA, Fletcher CS, McKeown A, Murphy HT. Assessment of monitoring power for highly mobile vertebrates. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2012; 22:374-383. [PMID: 22471097 DOI: 10.1890/11-0132.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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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Tulsiani SM, Cobbold RN, Graham GC, Dohnt MF, Burns MA, Leung LKP, Field HE, Smythe LD, Craig SB. The role of fruit bats in the transmission of pathogenic leptospires in Australia. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2011; 105:71-84. [PMID: 21294951 PMCID: PMC4089791 DOI: 10.1179/136485911x12899838413501] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 11/10/2010] [Accepted: 11/12/2010] [Indexed: 10/31/2022]
Abstract
Although antileptospiral antibodies and leptospiral DNA have been detected in Australian fruit bats, the role of such bats as infectious hosts for the leptospires found in rodents and humans remains unconfirmed. A cohort-design, replicated survey was recently conducted in Far North Queensland, Australia, to determine if the abundance and leptospiral status of rodents were affected by association with colonies of fruit bats (Pteropus conspicillatus spp.) via rodent contact with potentially infectious fruit-bat urine. In each of four study areas, a 'colony site' that included a fruit-bat colony and the land within 1500 m of the colony was compared with a 'control site' that held no fruit-bat colonies and was >2000 m from the nearest edge of the colony site. Rodents were surveyed, for a total of 2400 trap-nights, over six sampling sessions between September 2007 and September 2008. A low abundance of rodents but a high carriage of leptospires in the rodents present were found to be associated with proximity to a fruit-bat colony. For example, means of 0·4 and 2·3 fawn-footed melomys (Melomys cervinipes) were collected/100 trap-nights at sites with and without fruit-bat colonies, respectively (P<0·001), but the corresponding prevalences of leptospiral carriage were 100% and 3·6% (P<0·001). Such trends were consistent across all of the sampling sessions but not across all of the sampling sites. Leptospires were not isolated from fruit bats by culture, and the role of such bats in the transmission of leptospires to rodents cannot be confirmed. The data collected do, however, indicate the existence of a potential pathway for transmission of leptospires from fruit bats to rodents, via rodent contact with infectious fruit-bat urine. Fruit bats may possibly be involved in the ecology of leptospires (including emergent serovars), as disseminators of pathogens to rodent populations. Stringent quantitative risk analysis of the present and similar data, to explore their implications in terms of disease prevalence and wildlife population dynamics, is recommended.
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Affiliation(s)
- S M Tulsiani
- School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
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11
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Brown GW, Scroggie MP, Choquenot D. Precision and accuracy of flyout counts of the common bent-wing bat (Miniopterus schreibersii). ACTA CHIROPTEROLOGICA 2008. [DOI: 10.3161/150811008x331162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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12
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SHILTON LOUISEA, LATCH PETERJ, MCKEOWN ADAM, PERT PETINA, WESTCOTT DAVIDA. Landscape-scale redistribution of a highly mobile threatened species, Pteropus conspicillatus (Chiroptera, Pteropodidae), in response to Tropical Cyclone Larry. AUSTRAL ECOL 2008. [DOI: 10.1111/j.1442-9993.2008.01910.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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13
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Welbergen JA. Variation in twilight predicts the duration of the evening emergence of fruit bats from a mixed-species roost. Anim Behav 2008. [DOI: 10.1016/j.anbehav.2007.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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14
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Fleming PJS, Tracey JP. Some human, aircraft and animal factors affecting aerial surveys: how to enumerate animals from the air. WILDLIFE RESEARCH 2008. [DOI: 10.1071/wr07081] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Aerial surveys of wildlife involve a noisy platform carrying one or more observers moving over animals in order to quantify their abundance. This simple-sounding system encapsulates limits to human visual acuity and human concentration, visual attention, salience of target objects within the viewed scene, characteristics of survey platforms and facets of animal behaviours that affect the detection of animals by the airborne observers. These facets are too often ignored in aerial surveys, yet are inherent sources of counting error. Here we briefly review factors limiting the ability of observers to detect animals from aerial platforms in a range of sites, including characteristics of the aircraft, observers and target animals. Some of the previously uninvestigated limitations identified in the review were studied in central and western New South Wales, showing that inaccuracies of human memory and enumeration processes are sources of bias in aerial survey estimates. Standard protocols that minimise or account for the reviewed factors in aerial surveys of wildlife are recommended.
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van der Ree R, McDonnell MJ, Temby I, Nelson J, Whittingham E. The establishment and dynamics of a recently established urban camp of flying foxes (Pteropus poliocephalus) outside their geographic range. J Zool (1987) 2006. [DOI: 10.1111/j.1469-7998.2005.00005.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Forsyth DM, Scroggie MP, McDonald-Madden E. Accuracy and precision of grey-headed flying-fox (Pteropus poliocephalus) flyout counts. WILDLIFE RESEARCH 2006. [DOI: 10.1071/wr05029] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The principal method for estimating the abundance of bats in roosts is to count the number of bats exiting the roost at dusk (‘flyout counts’). We hypothesised that the accuracy and precision of flyout counts decrease non-linearly as the number of bats moving per unit of time increases, and that accuracy increases with observer experience. To test these hypotheses, we filmed grey-headed flying-foxes (Pteropus poliocephalus) exiting a roost in Melbourne on three consecutive evenings. The film was slowed and the number of flying-foxes flying-out in 30-s intervals was counted and assumed to be the true abundance. Thirteen other observers independently counted the number of flying-foxes flying-out in real time. We formulated our hypotheses into candidate models and compared support for these models using information-theoretic methods. Non-linear models had much greater support than linear models for all three flyouts. There was undercounting in two flyouts and overcounting in the third. There was good support for an effect of observer experience in one of the flyouts, but less support in the others. Precision declined as the true abundance increased in all three flyout counts. Our results indicate that accuracy, precision and observer effects vary with the dynamics of each flyout, and suggest that under some conditions flyout counts will often provide both inaccurate and imprecise estimates of abundance.
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Dallimer M, King T, Cope D, Borge Jiana M. Estimation of population density of Eidolon helvum on the island of Príncipe, Gulf of Guinea / Estimation de densité de population de Eidolon helvum sur l'île de Príncipe, Golfe de Guinée. MAMMALIA 2006. [DOI: 10.1515/mamm.2006.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractEidolon helvum is a widespread African fruit bat. It is migratory and can form colonies of millions of individuals. On Príncipe, in the Gulf of Guinea, there are seemingly large numbers of E. helvum . Here, they have lost their migratory behaviour and rely on the availability of the year-round food resources on the island, which is small (128 km
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