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Title: Human-provisioned foods reduce gut microbiome diversity in American black bears ( Ursus americanus )

The distal gut is home to the dynamic and influential gut microbiome, which is intimately linked to mammalian health by promoting and facilitating countless physiological functions. In a time of increased anthropogenic pressures on wildlife due to widespread habitat destruction, loss of natural prey/foods, and rapid urbanization, the study of wildlife gut microbiomes could prove to be a valuable tool in wildlife management and conservation. Diet is one of the most influential determinants of a host’s gut microbiome; yet many wildlife agencies allow baiting to facilitate wildlife harvest, although the impact of human-provisioned foods on wildlife gut health is largely unknown. We used stable isotope analysis derived from carbon (δ 13C) to index the use of human-provisioned foods by 35 legally harvested American black bears (Ursus americanus), and16S rRNA gene amplicon sequencing to examine the impact of human-provisioned foods on the gut microbial diversity of black bears. We found that greater long-term consumption of human-provisioned foods was associated with significantly reduced microbial species richness and phylogenetic diversity. Our results indicate that consumption of anthropogenic foods through baiting significantly alters the mammalian gut microbiome.

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Publication Date:
Journal Name:
Journal of Mammalogy
Page Range or eLocation-ID:
p. 339-346
Oxford University Press
Sponsoring Org:
National Science Foundation
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