Wild Birds Pose Unique Food Safety Threats in the US Southeast.

Natural areas near farmland can provide refuge for birds that contribute to natural pest control. However, birds can endanger food safety by defecating on or near produce. Work in the western US suggests that Campylobacter spp. are the potential foodborne pathogens most commonly associated with wild birds and that pathogen prevalence is higher in landscapes dominated by animal agriculture. However, relatively little is known about other fresh-market-produce growing regions. Working on produce farms in the Southeastern US, we characterized bird communities, tested bird feces deposited on crop foliage for Campylobacter and Salmonella, and searched for landscape features associated with heightened bird-associated food safety risks. We found that bird communities on farms were generally similar across ecoregions. Campylobacter was never detected from bird feces deposited on crop foliage, but Salmonella was detected in 8.6% of fecal samples. Salmonella prevalence in crop-surface-collected bird feces was highest when farms also produced livestock and when wetland cover was prevalent in the landscape. Overall, our results suggest that on-farm livestock production may be an indicator of bird-associated food safety risks in the Southeast, as in the West. We suggest there may be some similarities, but important differences, in food safety risks posed by birds in different US produce growing regions.