A new study reveals that five key forests in Central America provide vital wintering and stopover habitats for numerous migratory bird species from North America. These forests shelter significant portions of global populations for birds like Wood Thrushes and Cerulean Warblers, many of which are declining rapidly. However, illegal cattle ranching is accelerating deforestation, threatening both birds and local communities.
Every spring, songs of Wood Thrushes, Cerulean Warblers, and Golden-winged Warblers return to eastern North America, but these birds rely heavily on Central America's Five Great Forests for survival during the rest of the year. A study by the Wildlife Conservation Society and the Cornell Lab of Ornithology, published in Biological Conservation, analyzed millions of eBird sightings to show that these forests—from southern Mexico to northern Colombia—host between one-tenth and nearly one-half of the global populations of 40 migratory species.
The Five Great Forests include the Selva Maya spanning Mexico, Belize, and Guatemala; the Moskitia in Honduras and Nicaragua; Indio Maíz-Tortuguero; La Amistad; and Darién. They form an ecological corridor roughly the size of Virginia, also home to jaguars, tapirs, and scarlet macaws. Key findings indicate more than one-third of the world's Kentucky Warblers and nearly one-quarter of Wood Thrushes and Golden-winged Warblers winter there. Over 40 percent of Cerulean Warblers, which have declined by more than 70 percent since 1970, pass through during spring migration.
"What happens in Central America directly affects the birds we love in the United States and Canada," said Anna Lello-Smith, lead author and conservation scientist at WCS. "These forests aren't just tropical wilderness—they're at the heart of migration, sustaining many of our birds for more than half the year."
Yet these habitats are vanishing quickly. The Selva Maya and Moskitia have lost a quarter of their area in 15 years, mainly to illegal cattle ranching, with nearly one-third of the Moskitia gone in 20 years. "If we lose the last great forests of Central America—and we are—we lose the birds that define our eastern forests in North America," warned Jeremy Radachowsky, WCS Regional Director for Mesoamerica.
The study maps connections to North American breeding areas like the Appalachians, Mississippi Delta, Great Lakes, New England, and regions around New York City, calling them "sister landscapes." Indigenous and local communities are countering threats through land restoration, fire prevention, and sustainable practices like allspice and cacao production. "Every hectare we protect in Central America has ripple effects for birds and people across the hemisphere," Lello-Smith added.