During the days of mammoths and saber-toothed cats, California Condors thrived over much of the continent. Today, they're one of the most endangered birds in the US. The condor's main survival problem is high mortality due to lead poisoning. Condors eat animal carcasses, often containing…

The modern chicken, a descendant of the Red Junglefowl, was domesticated thousands of years ago. But chickens haven't always just been farm animals. During the Iron Age in the Middle East, the rooster's morning call became a symbol for chickens’ divine connection to the sun. When chickens…

Barn Swallows have adapted to nesting near people, and build their cup-shaped mud nests in barns or garages, or on protected ledges, often near each other. The good news? These twittery, flittery birds love to eat the insects that humans consider pesky. Imagine: 60 insects per hour, a…

When a Sage Thrasher, perched on a clump of sagebrush, tips its head back to sing, the notes rush forth. They often sing non-stop for at least two minutes. In stark comparison, the song of this Brewer’s Blackbird lasts barely a second. And the Henslow’s Sparrow values brevity even more…

The Bee Hummingbird, found only in Cuba, is the smallest bird in the world. An absolute miniature, even among hummingbirds, it measures only two and a quarter inches long. Often mistaken for bees, they weigh less than a dime. The female builds a nest barely an inch across, and lays eggs…

Imagine this Black-capped Chickadee flying toward its nest, carrying fresh insects for its chicks. A moment later, it emerges with a tiny white pouch in its bill. The chickadee drops the object into the vegetation below. That outgoing payload is a fecal sac, a remarkable adaptation found…

Heidi Hoelting, a musician, listens carefully to the songs of birds. In her piano studio at her home in the woods, she wrote down several variations of the different sounds a Song Sparrow makes. In this BirdNote, Nancy Rumbel plays some of those variations on a bamboo whistle. Listen to…

This Great Horned Owlet - about 2-1/2 months old and already as big as its parents - is quite well feathered, although its underparts remain downy. Its wing and tail feathers are developing nicely, and it has begun to make short flights. By mid-May, the owlet still relies almost entirely…

Hummingbirds need to consume five times their body weight each day. This Rufous Hummingbird of the West is looking for flowering plants to quench that mighty thirst on its spring migration. A feeder would work, too. Put a hummingbird feeder up in your yard, and see who turns up!

A pair of White-throated Swifts twists and turns, sailing through the air. Dashing headlong across the canyon toward an unyielding wall, the birds disappear at the last second into a slender crevice. This swift is aptly named — and doubly so. The White-throated Swift is among the fastest…