Cooperative Fish and Wildlife Research Units Program: New York
Education, Research and Technical Assistance for Managing Our Natural Resources

The New York Breeding Bird Atlas (BBA) provides the best, and often only, estimate of bird species distributions across New York State. The third BBA will allow for trends between atlas periods to be used to analyze population trends for hundreds of species of
birds. Statewide distribution data will enable estimating current distribution, identification of key bird conservation focus areas such as Important Bird Areas (IBAs) and grassland breeding bird conservation centers and evaluate trends in species distributions.

NYCFWRU will estimate occupancy of select bird species using an occupancy modeling framework where repeated visits to the same location, by the same observer are used. NYCFWRU will integrate covariates such as latitude, longitude, landcover types, and the effect of year. This will allow for the estimation of a seasonal occupancy model by dividing the year into 2-week periods and estimating seasonal occupancy and detectability. Use of eBird ‘observer expertise’ scores will be integrated as a covariate to help explain inter-observer variation in detectability. Models will be fit in R with the ‘occur’ function package of ‘unmarked’. In addition, the multi-species occupancy model framework can be used to estimate species richness. If data are available on counts, we can join count data with occupancy data in an integrated model and/or use repeated surveys to produce abundance maps with binomial N-mixture models that include environmental covariates.