Bird migration

Trackers may tip a warbler’s odds of returning to its nest

Cerulean warbler
Cerulean warblers wearing geolocators on their backs may be less likely to complete the usual return flight from South America to their breeding grounds in the eastern United States.

Strapping tiny trackers called geolocators to the backs of birds can reveal a lot about where the birds go when they migrate, how they get there and what happens along the way. But ornithologists are finding that these cool backpacks could have not-so-cool consequences.

Douglas Raybuck of Arkansas State University and his colleagues outfitted some Cerulean warblers (Setophaga cerulea) with geolocators and some with simple color tags to test the…

How You Can Help Protect Migrating Birds

Warm weather is on its way back to the Northern Hemisphere, and with it, flock upon flock of migratory birds. The birds’ journey is not without risks, including some we’ve created, but there’s also a lot we can do to help, as the Sierra Club explains.

Cats remain the biggest killer of American birds, but colliding with buildings is a close second, killing between 100 million and 1 billion birds each year as they crash into stationary objects. The collisions are often the result of light pollution, which can disorient night-flying birds, and shiny building materials that reflect the sky. Because crashes are common during migrations, these periods are a great time for researchers to collect data on how, where, and why the accidents happen.

To do that, they need people power. Bird lovers across the country are turning up in droves to their…