Land transformation into agricultural areas and the intensification of management practices represent two of the most devastating threats to biodiversity worldwide. Within this study, we investigated the effect of intensively managed agroecosystems on bat activity and species composition within two focal areas differing in landscape structure. We sampled bats via acoustic monitoring and insects with flight interception traps in banana and pineapple monoculture plantations and two nearby protected forested areas within the area of Sarapiquí, Costa Rica. Our results revealed that general occurrence and feeding activity of bats was higher above plantations compared to forested areas. We also recorded higher species richness at recording sites in plantations. This trend was especially strong within a fragmented landscape, with only four species recorded in forests, but 12 above pineapple plantations. Several bat species, however, occurred only once or twice above plantations, and forest specialist species such as Centronycteris centralis, Myotis riparius and Pteronotus mesoamericanus were only recorded at forest sites. Our results indicated, that mostly mobile open space and edge foraging bat species can use plantations as potential foraging habitat and might even take advantage of temporal insect outbreaks. However, forests are vital refugia for several species, including slower flying forest specialists, and thus a prerequisite to safeguard bat diversity within agricultural dominated landscapes.

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Habitat alteration for agriculture can negatively affect wildlife physiology and health by decreasing diet diversity and increasing exposure to agrochemicals for animals foraging in altered landscapes. Such negative effects may be mediated by the disruption of the gut microbiota (termed dysbiosis), yet evidence for associations between habitat alteration, wildlife health, and the gut microbiota remains scarce. We examine the association between management intensity of banana plantations and both the body condition and gut microbiota composition of nectar-feeding bats Glossophaga soricina, which commonly forage within banana plantations across Latin America. We captured and measured 196 bats across conventional monocultures, organic plantations, and natural forests in Costa Rica, and quantified gut microbiome bacterial phylogenetic diversity using 16S rRNA amplicon sequencing. We found that gut microbiota from bats foraging in conventional monocultures were overall less phylogenetically diverse than those from bats foraging in organic plantations or natural forests, both of which were characterized by diverse bacterial assemblages and individualized microbiota. Despite lower diversity, co-occurrence network complexity was higher in conventional monocultures, potentially indicating altered microbial interactions in agricultural landscapes. Bats from both organic and conventional plantations tended to be larger and heavier than their forest counterparts, reflecting the higher food supply. Overall, our study reveals that whilst both conventional monocultures and organic plantations provide a reliable food source for bats, conventional monocultures are associated with less diverse and potentially dysbiotic microbiota, whilst organic plantations promote diverse and individualized gut microbiota akin to their natural forest-foraging counterparts. Whilst the long-term negative effects of anthropogenically-altered microbiota are unclear, our study provides further evidence from a novel perspective that organic agricultural practices are beneficial for wildlife health.

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Por las estrechas relaciones que pueden establecer con los ambientes que ocupan, los murciélagos han sido sugeridos como bioindicadores ideales de la perturbación de los ecosistemas naturales. Analizamos la composición de especies de murciélagos insectívoros aéreos, por medio de llamadas, en ambientes contrastantes como claros y bosques tropicales, con la finalidad de analizar la influencia de estas perturbaciones naturales sobre la composición de los ensambles. Durante mayo del 2009 se evaluó la presencia de murciélagos insectívoros por medio de un sistema de grabación ultrasónico de división de frecuencia. Se encontraron diferencias significativas en la composición entre bosques y claros (Jaccard= 0,308), con una alta variación en la composición dentro de los sitios de bosque y una muy alta similitud entre los sitios de claros. Se discute el efecto potencial de los claros en la composición y uso por murciélagos insectívoros y el efecto potencial sobre el método de muestreo.