Analysis of bacterial communities associated with Mountain Chickadees (Poecile gambeli) across urban and rural habitats

Abstract

Host associated microbial communities play important roles in wildlife health, but these dynamics can be influenced by environmental factors. Urbanization has numerous consequences on wildlife; however, the degree to which wildlife associated bacterial communities and potential bacterial pathogens vary across urban to rural/native habitat gradients remains largely unknown. We used 16S rRNA gene amplicon sequencing to examine bacterial communities found on mountain chickadee (Poecile gambeli) feathers and nests in urban and rural habitats. Feathers and nests in urban and rural sites had similar abundances of major bacterial phyla and dominant genera with pathogenic members. However, richness of bacterial communities and potential pathogens on birds were higher in urban habitats, and potential pathogens accounted for some of the differences in bacterial occurrence between urban and rural environments. We predicted habitat using potential pathogen occurrence with a 90% success rate for feather bacteria, and a 72.2% success rate for nest bacteria, suggesting an influence of urban environments on potential pathogen presence. We additionally observed similarities in bacterial communities between nests and their occupants, suggesting bacterial transmission between them. These findings improve our understanding of the bacterial communities associated with urban wildlife and suggest that urbanization may impact wildlife associated bacterial community compositions.

Microbiology of the built environment: harnessing human-associated built environment research to inform the study and design of animal nests and enclosures

“…Both humans and other animals intentionally decrease the abundance of pathogens with various hygiene practices and the use of antimicrobials. This includes either the direct cleaning of their bodies and waste removal (95)(96)(97)(98) or through the curation of antimicrobial-producing taxa (7,99). It is unknown, however, whether the presence of antimicrobial-producing taxa in nests increases selection for ARGs on interior surfaces, but it can be posited that any selection for resistance is less frequent in natural nests than in artificial enclosures.…”

Effects of urban sugar water feeding on bird body condition and avian diseases

“…5,6,[11][12][13] Urbanization can be associated with an increase in urban bird densities, especially around supplementary feeders, which in turn results in a higher chance of avian parasite transmission and disease outbreaks. [14][15][16][17][18][19][20][21][22] In particular, more frequent feeder visits can lead to increased transmission of avian viruses and ectoparasites through direct body contact, and gastrointestinal parasites through accumulation of contaminated feces. 4,6,15,[22][23][24][25][26][27] There is also the potential for Salmonella enterica, the agent of salmonellosis infection, transmission to humans via bird feeding.…”