Data and Analysis Scripts

This collection contains the data and analysis scripts for the southbound migration quantile analysis performed in "Quantifying phenological landmarks of migration shows non-uniform use of the Caribbean by shorebirds" in Ecology and Evolution by Cañizares, Edwards, and Reed. Please see readme.txt for full details. Current methods are insufficient to characterize phenology of passage migrants with potentially complex migration curves, particularly when some individuals may be present outside of the migration periods. Here we present a novel method that leverages a well-established statistical approach (generalized additive models) to systematically identify migration phenology for complex passage migrant species with individuals that remain beyond migration. Our method identifies the active migration period using derivatives of a fitted GAM, and then calculates phenology metrics based on quantiles of that migration period. This enabled us to estimate dates of migration landmarks and identify patterns of southbound migration in a suite of North American shorebird species as they travel through different regions in the Caribbean.