Abstract The Gulf of Mexico hosts major migration pathways linking birds breeding in the United States and Canada to nonbreeding areas in Central and South America, but little is known about the role of western Cuba within these pathways. Long-term migration monitoring has been missing from western Cuba, but since 2015 a post-breeding migration banding station has operated annually at the tip of the Guanahacabibes Peninsula. Our objective was to investigate patterns of post-breeding migration in western Cuba combining multiple sources of data to examine connectivity and timing of migration for 15 passerine species. We used feather stable-hydrogen isotopes (δ2Hf) to estimate breeding origins and used constant-effort mist netting and eBird Status and Trends relative abundance estimates to examine post-breeding migration and arrival timing in Cuba and the surrounding regions. The majority of species had southeastern origins (e.g., Setophaga ruticilla American Redstart), which is consistent with the breeding distribution of the most frequently encountered species in Cuba during the stationary nonbreeding period. Origins among boreal breeding species were more varied than expected, assuming parallel migration, with an unexpectedly high representation of northwestern breeding populations in species like Parkesia novaboracensis (Northern Waterthrush) and broad continent-wide origins in species like Catharus ustulatus (Swainson’s Thrush). Comparing timing of migration in Cuba to the surrounding regions, we found evidence supporting the movement of migrants through western Cuba to the Yucatán Peninsula/ Central America for nine species. Although, these patterns are speculative, and eBird Status and Trends data were highly variable, these results indicate that western Cuba, and the Guanahacabibes Peninsula in particular, is a region used by several species of Neotropical migrant passerines during post-breeding migration. More research is needed on stopover ecology in Cuba and targeted VHF radio tagging within the Gulf of Mexico to better understand how migratory birds use this important area during post-breeding migration.
Hobson et al. (Sat,) studied this question.