Candidate set of models used to identify the relative influence of covariates on the probability an individual bird sampled during the breeding season tested positive for Avian Influenza Virus (AIV).

Abbreviations are: DEMO = Demographic variables of age, age unknown, sex, sex unknown, and species; MONTH = sample month; DBZ = number of days temperature was below freezing during the six month overwintering season prior to each breeding season; and IAP = interval apparent prevalence of AIV within the local watershed during the six month overwintering period prior to each breeding season.Notes: Only the top five models are shown for clarity.†Number of estimable parameters.‡Maximized value of the logarithm of the likelihood function.§Difference in AIC between a given model, r, and the model with the minimum AIC.*Aikaike weight, wr, is the probability that the estimated model, r, was the best model given the data.