Exploring Bird Gut Microbiota Through Opportunistic Fecal Sampling: Ecological and Evolutionary Perspectives

Area of Science:

• Avian ecology and wildlife health
• Microbiome research
• Environmental science and conservation

Background:

• Wetland ecosystems are crucial for avian populations but face degradation.
• Bird health is intrinsically linked to their intestinal microbiota, influenced by diet and local conditions.
• Previous research identified dietary variations in marsh birds within a French Ramsar site.

Purpose of the Study:

• To evaluate the utility of noninvasively collected fecal samples for characterizing avian intestinal microbiota.
• To investigate the influence of bird traits and environmental factors on fecal microbiota composition using 16S rRNA metabarcoding.
• To explore the relationship between bird gut microbiota and their wetland habitats.

Main Methods:

• Collected 52 fecal samples from nine bird species during the breeding season at seven rural and peri-urban locations.
• Utilized 16S rRNA metabarcoding to analyze bacterial composition in fecal samples.
• Applied multivariate analyses to associate microbiota variations with bird traits (trophic guild, ecology, body length) and environmental factors (habitat location, pond surface).

Main Results:

• Firmicutes and Proteobacteria were the predominant phyla, with genus abundance varying by species.
• The potential enteropathogen *Campylobacter* was more prevalent in peri-urban samples.
• Significant variations in microbiota were linked to bird ecology, body length, pond surface, and habitat location, with a weak host phylogeny correlation.

Conclusions:

• Opportunistically collected fecal samples are a viable, low-impact tool for studying avian gut microbiota.
• Fecal microbiota composition reflects ecological factors and bird traits in wetland environments.
• This method aids in understanding the interplay between bird health, microbiota, and habitat quality.