Weighing about as much as four paperclips, Bushtits are smaller than many hummingbirds. And they take full advantage of their diminutive size. While larger insect-eaters forage on the upper surfaces of leaves, Bushtits hang beneath them, plucking all the tiny insects and spiders hiding out…

The glorious song of the male Sage Thrasher rings out every spring from tracts of sagebrush throughout the West. Sagebrush was once widespread in the Great Basin region, and so were the thrashers. But huge areas of sagebrush were turned into alfalfa and potato farms, and the songs of the…

For such a small owl, the Northern Saw-whet has a lot to say. And a lot of ways to say it. Males weigh about as much as an American Robin. And they send out at least 11 different calls, including “toot-toot-toot” advertising calls, from late January through May. The rate of calling is…

Some species of birds try to save energy by tricking others into incubating their eggs. But if the parasitic female is a related species, she may have an advantage. After studying the nests of Common Eiders, such as the one pictured here, researchers at the University of Gothenburg in…

During winter and early spring, Great Blue Herons build their nests high in the treetops. The male delivers the supplies to the nest site stick by stick, as the female arranges things. It’s the perfect childhood home for their young, made without blueprints, architects or engineers. But by…

In late winter, White-throated Sparrows erupt into song, easily set to human words: “Old Sam Peabody, Peabody, Peabody.” Or “Oh, sweet Canada, Canada, Canada.” But something changed since those classic memory aids were coined. Sixty years later, the bird sings a simpler, shorter song. Bird…

If any bird is an anomaly, it's the Wilson's Phalarope. In a birdbook, Wilson's Phalaropes are found among the sandpipers. But they forage while swimming. Spinning like tops, they create an upwelling, pulling food to the surface. The breeding of Wilson's Phalaropes is anomalous, too…

Most wrens in North America are small, furtive birds that stay deep in the vegetation. But the Cactus Wren is large, bold, and brassy. These wrens are well adapted to the desert and can get all the moisture they need from their food. Cactus Wren nests are a regular sight in their range of…

Crane Hawks of Central and South America and African Harrier-Hawks both have legs that bend forward and backward. Each bird’s wonderfully peculiar leg adaptation is completely original - it evolved all on its own - even though the end result is the same. Scientists call this convergent…

That’s not a distant dog barking. It’s a Black Skimmer in flight, at the Chincoteague National Wildlife Refuge in Virginia. This striking, black-and-white bird with a red bill and red feet has a most unusual way of feeding. It flies low along the surface of the water with its beak open…