"WASHINGTON — A bay-breasted warbler weighs about the same as four pennies, but twice a year makes an extraordinary journey. The tiny songbird flies nearly 4,000 miles (6,437 kilometers) between Canada’s spruce forests and its wintering grounds in northern South America.

“Migratory birds are these little globetrotters,” said Jill Deppe, the senior director of the migratory bird initiative at the National Audubon Society.

A new online atlas of bird migration, published on Thursday, draws from an unprecedented number of scientific and community data sources to illustrate the routes of about 450 bird species in the Americas, including the warblers.

The Bird Migration Explorer mapping tool, available free to the public, is an ongoing collaboration between 11 groups that collect and analyze data on bird movements, including the Cornell Lab of Ornithology, Smithsonian Migratory Bird Center, the U.S. Geological Survey, Georgetown University, Colorado State University, and the National Audubon Society."

Christina Larson reports for the Associated Press September 15, 2022. [2]