title: An island paradigm on the mainland: host population fragmentation impairs the community of avian pathogens.
abstract: Emergent infectious diseases represent a major threat for biodiversity in fragmented habitat networks, but their dynamics in host metapopulations remain largely unexplored. We studied a large community of pathogens (including 26 haematozoans, bacteria and viruses as determined through polymerase chain reaction assays) in a highly fragmented mainland bird metapopulation. Contrary to recent studies, which have established that the prevalence of pathogens increase with habitat fragmentation owing to crowding and habitat-edge effects, the analysed pathogen parameters were neither dependent on host densities nor related to the spatial structure of the metapopulation. We provide, to our knowledge, the first empirical evidence for a positive effect of host population size on pathogen prevalence, richness and diversity. These new insights into the interplay between habitat fragmentation and pathogens reveal properties of a host-pathogen system resembling island environments, suggesting that severe habitat loss and fragmentation could lower pathogen pressure in small populations.
authors.affiliation: Department of Conservation Biology, Estación Biológica de Doñana (CSIC), c/Américo Vespucio s/n, 41092 Sevilla, Spain. matthias.voegeli@usask.ca
authors.forename: Matthias
authors.initials: M
authors.lastname: Vögeli
authors.forename: Jesús A
authors.initials: JA
authors.lastname: Lemus
authors.forename: David
authors.initials: D
authors.lastname: Serrano
authors.forename: Guillermo
authors.initials: G
authors.lastname: Blanco
authors.forename: José L
authors.initials: JL
authors.lastname: Tella
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D001424:Bacterial Infections / Q000453:epidemiology / Q000382:microbiology; D001715:Bird Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000469:parasitology / Q000821:virology; D021821:Communicable Diseases, Emerging / Q000453:epidemiology / Q000209:etiology / Q000662:veterinary; D017753:Ecosystem; D054884:Host-Pathogen Interactions / Q000502:physiology*; D010271:Parasites / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D010273:Parasitic Diseases, Animal / Q000453:epidemiology / Q000469:parasitology; D046109:Passeriformes / Q000502:physiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D011156:Population Density; D015995:Prevalence; D013045:Species Specificity; D014777:Virus Diseases / Q000453:epidemiology / Q000821:virology; D014780:Viruses / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*