Meeting Abstract
Pathogens are known to have a strong influence on fitness of wild birds. A well-known dynamic of disease ecology is the link between increased population density and increased pathogen prevalence. Birds often gather at bird feeders in large densities, creating an increased likelihood of disease transmission around these resources. Over a three-year period, we surveyed individuals from nine species of birds for the presence of two different pathogens that can have a serious impact on the overall health of birds: the pathogenic bacteria, Mycoplasma gallisepticum (a causative agent of conjunctivitis) and Avipoxvirus (the causative agent of avian pox). To estimate the impact of these diseases on host health, we also examined immune and physiological profiles of each bird. We used both field identification of pathological symptoms and molecular techniques to identify pathogens. We found severe symptoms to be more common in feeder-using birds than in songbirds at sites without feeders. Songbirds hosting these pathogens showed greater heterophil to lymphocyte ratios, lower total antioxidant capacity, and were in overall worse body condition. PCR analysis was also utilized to detect either pathogen in birds that may have been infected but not showing visual symptoms of disease. Overall, this study reveals important disease dynamics associated with bird feeding activities in a community of free-living birds.
