Another Silent Spring? Analyzing Patterns in an Emerging Epizootic in North America
Birds with beak deformities have been documented throughout the literature, although occurrences are rare and not usually extensive within populations. Sudden emergence of deformities in large clusters of animals may indicate a dramatic change in the environment. Recent reports of unprecedented proportions of birds with beak deformities in Alaska caused alarm in the scientific community and prompted this study. We analyzed data on locations of bird beak deformities in North America to detect spatial patterns and correlations with environmental and natural history traits. We used a meta-analysis and statistical techniques to determine significant relationships and strength of effect between deformity and several variables that make certain species more susceptible to deformity, including migratory behavior, diet, age of deformed bird and habitat characteristics. We expect to find higher levels of deformity in species with fish-based diets, which serve as a pathway for biomagnification of toxins. Point locations of deformities were georeferenced and overlaid with data such as land use, environmental contamination and species range to determine spatial patterns. Our study focused on the Great Lakes and Pacific Northwest regions due to high rates of deformity found within populations in those areas. We expect a strong relationship between rates of deformity and levels of environmental contamination. Results from this study can be applied to assist future research efforts focused on determining the etiology of beak deformity.
Faculty Mentor: Shaily Menon, Biology
Page last modified July 25, 2011