Species and behavioral patterns of wild birds invading a cow barn in the subtropical region: A case study in the central region of Okinawa-jima Island, Japan

Wild birds can spread infectious diseases to livestock over wide areas. Therefore, measures to prevent wild birds from entering livestock barns are crucial. However, there is little scientific data on wild bird and livestock interactions in livestock barns. In this study, we conducted a visual survey of the species composition of wild birds flying into the sanitation control zone of a livestock farm located in central Okinawa-jima Island, Japan. Additionally, wild bird species and their behavioral patterns entering a cow barn from September to February were also surveyed. In this study, more than 20 species of wild bird visited the sanitation control zone, with resident breeders visiting more often than migratory birds. The diets of wild birds indicated a wide range of feeding habits. A total of five wild bird species entered the cow barn during the study period, which was much fewer than the number of species that visited the sanitation control zone. Rock doves were the most frequent visitors in the cow barn, and had the most diverse behavioral patterns and direct contact with cattle. The frequency of birds entering the feed trough and walking inside the cattle pen, where interactions with cattle may occur, varied with the time of day, suggesting that the amount of compound feed and cattle dung used as feed resources may be influential. Migratory birds were also observed among the wild birds visiting the sanitation control zone and entering the barn, suggesting seasonality in the arrival of wild birds. Wild birds that visited livestock farms more frequently did not necessarily invade or enter the cow barns. The difference between the frequency of visits to the farm and their entry into the barn may be related to the dietary habits of wild birds, environmental preferences, habituation to humans and domestic animals, and learning about husbandry and management. This study quantified and clarified species-specific behavioral patterns of wild birds invading the barn in a subtropical island. Future research based on the ecology of wild birds could provide information that will lead to the evaluation of quarantine risks on livestock farms and the formulation of specific countermeasures.