Data and Model-based Estimates from Black Brant (Branta bernicla nigricans) Fall Age Ratio Surveys at Izembek Lagoon, Alaska

These data are in two tables relating to fall age ratios (number of juvenile birds : total birds aged) of Black brant (Branta bernicla nigricans) staging in Izembek Lagoon, Alaska since 1963. The first file is observation data for the birds' age classes during surveys and associated survey characteristics. The second file contains model-based estimates of age ratios by year along with SE, and 95% Bayesian credible intervals around estimates.