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1.
Biol Conserv ; 234: 165-171, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31937976

RESUMEN

Madagascar is home to three endemic species of Old World Fruit Bat, which are important pollinators and seed dispersers. We aimed to quantitatively assess population trajectories for the two largest of these species, the IUCN-listed 'Vulnerable' Eidolon dupreanum and Pteropus rufus. To this end, we conducted a longitudinal field study, in which we live-captured E. dupreanum and P. rufus, estimated species-specific fecundity rates, and generated age-frequency data via histological analysis of cementum annuli layering in tooth samples extracted from a subset of individuals. We fit exponential models to resulting data to estimate annual survival probabilities for adult bats (s A = .794 for E. dupreanum; s A = .511 for P. rufus), then applied Lefkovitch modeling techniques to infer the minimum required juvenile survival rate needed to permit longterm population persistence. Given estimated adult survival, population persistence was only possible for E. dupreanum when field-based fecundity estimates were replaced by higher values reported in the literature for related species. For P. rufus, tooth-derived estimates of adult survival were so low that even assumptions of perfect (100%) juvenile annual survival would not permit stable population trajectories. Age-based survival analyses were further supported by longitudinal exit counts carried out from 2013-2018 at three local P. rufus roost sites, which demonstrated a statistically significant, faintly negative time trend, indicative of subtle regional population declines. These results suggest that Malagasy fruit bat species face significant threats to population viability, with P. rufus particularly imperiled. Immediate conservation interventions, including habitat restoration and cessation of legally sanctioned bat hunting, are needed to protect Madagascar's fruit bats into the future.

2.
Virol J ; 12: 42, 2015 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-25888853

RESUMEN

BACKGROUND: Bats are amongst the natural reservoirs of many coronaviruses (CoVs) of which some can lead to severe infection in human. African bats are known to harbor a range of pathogens (e.g., Ebola and Marburg viruses) that can infect humans and cause disease outbreaks. A recent study in South Africa isolated a genetic variant closely related to MERS-CoV from an insectivorous bat. Though Madagascar is home to 44 bat species (41 insectivorous and 3 frugivorous) of which 34 are endemic, no data exists concerning the circulation of CoVs in the island's chiropteran fauna. Certain Malagasy bats can be frequently found in close contact with humans and frugivorous bats feed in the same trees where people collect and consume fruits and are hunted and consumed as bush meat. The purpose of our study is to detect and identify CoVs from frugivorous bats in Madagascar to evaluate the risk of human infection from infected bats. METHODS: Frugivorous bats belonging to three species were captured in four different regions of Madagascar. We analyzed fecal and throat swabs to detect the presence of virus through amplification of the RNA-dependent RNA polymerase (RdRp) gene, which is highly conserved in all known coronaviruses. Phylogenetic analyses were performed from positive specimens. RESULTS: From 351 frugivorous bats, we detected 14 coronaviruses from two endemic bats species, of which 13 viruses were identified from Pteropus rufus and one from Eidolon dupreanum, giving an overall prevalence of 4.5%. Phylogenetic analysis revealed that the Malagasy strains belong to the genus Betacoronavirus but form three distinct clusters, which seem to represent previously undescribed genetic lineages. CONCLUSIONS: Our findings suggest that CoVs circulate in frugivorous bats of Madagascar, demonstrating the needs to evaluate spillover risk to human populations especially for individuals that hunt and consume infected bats. Possible dispersal mechanisms as to how coronaviruses arrived on Madagascar are discussed.


Asunto(s)
Quirópteros/virología , Infecciones por Coronaviridae/veterinaria , Coronaviridae/genética , Variación Genética , Animales , Coronaviridae/clasificación , Coronaviridae/aislamiento & purificación , Genes Virales , Geografía , Madagascar , Filogenia
3.
Sci Data ; 5: 180225, 2018 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-30351304

RESUMEN

The Government of Madagascar is trying to reduce deforestation and conserve biodiversity through creating new protected areas in the eastern rainforests. While this has many benefits, forest use restriction may bring costs to farmers at the forest frontier. We explored this through a series of surveys in five sites around the Corridor Ankeniheny Zahamena new protected area and adjacent national parks. In phase one a stratified random sample of 603 households completed a household survey covering demographic and socio-economic characteristics, and a choice experiment to estimate the opportunity costs of conservation. A stratified sub-sample (n = 171) then completed a detailed agricultural survey (including recording inputs and outputs from 721 plots) and wild-harvested product survey. The data have been archived with ReShare (UK Data Service). Together these allow a deeper understanding of the household economy on the forest frontier in eastern Madagascar and their swidden agricultural system, the benefits households derive from the forests through wild-harvested products, and the costs of conservation restrictions to forest edge communities.


Asunto(s)
Conservación de los Recursos Naturales/economía , Economía , Bosque Lluvioso , Conservación de los Recursos Naturales/estadística & datos numéricos , Conservación de los Recursos Naturales/tendencias , Economía/estadística & datos numéricos , Economía/tendencias , Humanos , Madagascar
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