Swainson’s warblers have only been documented about 60 times in Pennsylvania since they were first recorded at Bear Run in 1975. Western Pennsylvania is at the most northern edge of its range.

One female golden-cheeked warbler was spotted in early April, joining a male warbler that was spotted in May of last year, said Julie Collins, director of Dogwood Canyon Audubon Center.

If the Kentucky warbler hadn’t gotten caught in the net, scientists may have never known that species was present at Tremont. The female warbler had a brood patch — an area of featherless skin ...

This female Kentucky warbler was a rare find at the Tremont bird-monitoring station. Its capture this summer marked the first time the species had been collected at the site.

The female warbler had a brood patch, an area of featherless skin that means she’s currently raising young and that a male Kentucky warbler is likely nearby.

A female Galápagos yellow warbler falls asleep on her nest during a playback of cowbird calls, which usually provoke aggressive responses in mainland warblers. Researchers are realizing that ...

Female, left, and male Galapagos Yellow Warbler - picture by Caglar Akcay, Anglia Ruskin University ...

While Blackburnian warblers are not uncommon in mature conifer and mixed hardwood forests, they can be hard to see, since ...

One recent morning, trying to find the source of a warbler trill high in a white pine tree, I was rewarded with a brilliant ...