Birds at a suet feeder... What a burst of vitality on a chilly morning! What's the attraction? A cake of suet, suspended from a branch in a small wire feeder. Suet is beef fat, a high-energy food critical for birds' survival in the colder months. Suet is an especially strong magnet for…

For small songbirds, surviving a cold winter night can be challenging. Their bodies lose heat faster than those of larger birds. So little birds have found resourceful ways to stay warm — like huddling close together with other birds. But the Verdin, a tiny bird of the Southwest, does…

The two American species of dowitchers, Long-billed and Short-billed, are similar in appearance but have distinctive calls. And they’re some of the continent’s most dramatic songsters. On their northern breeding grounds, Short-billed Dowitchers ascend as high as 150 feet in the air then…

Hidden below the outer breast feathers of herons, pigeons, doves, tinamous, bustards and some parrots are patches of special down feathers. These feathers are never molted, and they grow continuously. The tips break down into a dust the consistency of talcum powder. Using a fringed claw on…

The call of the Common Loon brings to mind a summer visit to northern lakes. A "yodel" call is given by a male on his breeding territory. With his neck outstretched, the male waves his head from side to side, sending his eerie calls across forests and open water. The yodel entices females…

High in a leafless cottonwood, a female Great Horned Owl incubates two eggs. As light snow falls on her back, her mate roosts nearby. Since December, this pair has been hooting back and forth regularly at night. Great Horned Owls nest in winter, because the owlets, which hatch after a…

A Merlin hunts boldly from a high perch. A Peregrine Falcon dives on a hapless pigeon, with an air speed approaching 200 miles per hour. The Gyrfalcon can fly down even the fastest waterfowl in a direct sprint. A Prairie Falcon blends in with its background. And the smallest North American…

A chickadee comes in to the feeder, quickly grabs a seed, and flies away. It may return immediately, but it's more likely to wait its turn. When a whole flock of chickadees moves into the yard, it looks as if they form a living conveyer belt. One chickadee after another flies to the feeder…

During winter, the Greater Sage-Grouse is wholly reliant on its namesake species — sagebrush — for both shelter and for food. Scientists call this bird "sagebrush obligate," meaning it needs this plant to survive. In the spring, its diet shifts to insects and plants, as it gets ready for…

The cries of a Killdeer are familiar across most of the US during spring and summer. But where do they go in winter? Killdeer that breed in the southern half of the US and along the Pacific Coast are year-round residents. But those that breed in the northern US and Canada, where winter…