Meeting Abstract
The rapid effects of human land development present relatively recent and stark changes in the environment. Recent work in birds and humans suggests that urbanization may affect the composition of animal gut microbiomes. Factors driving observed differences between urban and rural gut microbiomes are unknown, but may include diet, geography, and/or pollution. To better understand these effects, we investigated the relationship between urbanization and the gut bacterial community of white-crowned sparrow populations in the San Francisco Bay area. We addressed three questions: 1) Which aspects of a bird’s environment influence their gut bacterial community? 2) Which host morphological characteristics best explain gut bacterial community? 3) Are these morphological characteristics mediating the relationship between host environment and gut bacterial community? We also assessed the effects of urbanization by examining the taxonomic composition of gut bacterial communities in birds across habitats. We find direct effects of environmental factors, including urban noise levels and territory land cover, as well as indirect effects through body size and condition, on alpha and beta diversity of gut microbial communities. Elucidating these effects provides a better understanding of how urbanization affects wild avian physiology.
