Wildlife microbiomes and the city: a systematic review of urban impacts on wildlife bacterial communities

Abstract

This systematic review aims to investigate how urban living influences the microbiome of wildlife. We included all studies that compared the bacterial communities of non-human vertebrate wildlife living inside vs outside cities, and/or across an urbanisation gradient. We found that the effect of urban living on bacterial diversity and community composition was not unidirectional: some studies found a positive association, others found a negative association, and some found no relationship. The definition of ‘urban’ was not specified in more than half of the studies, and when included, was not consistent across studies; paired with limited site replication in many studies, these features coul..