The raucous laughter of the Common Murre rings out from a nesting colony, high on a narrow ledge on a sea cliff. Precarious as their nest site is, Common Murres nest by the thousands along the Pacific Coast, perhaps millions north along the Bering Sea. Their eggs are pointed at one end and…

In parts of the United States, House Finches overlap with similar-looking Purple Finches. Their distinct songs help us sort them out. House Finch songs are jumbled and have a sharp, buzzy note — especially during the breeding season. Purple Finches’ songs, on the other hand, are smoother…

Not all blackbirds are mostly black. This Baltimore Oriole is orange! It’s named after Sir George Calvert, First Lord of Baltimore, whose coat-of-arms carried a gold and black design. In spring and summer, you may see these orioles in the Midwest and eastern US, lighting up the trees where…

Young birds leave their nests in different ways. Some shuffle tentatively along the nearest branch and practice flapping their wings, while others take the "big leap." Which path they take depends upon their species and the location of the nest. Young Great Horned Owls clamber out of the…

Meet three of the most fearsome predatory birds. The Northern Goshawk is a silver blur when it rockets toward an unsuspecting grouse. The Brown Snake-Eagle snatches six-foot cobras off the ground. And the Eurasian Eagle-Owl preys on animals as large as deer fawns.

When scientists looked at climate data for more than 8,500 robins’ nests in the US, they found that robins will nest only if the mean noon temperature is between 45 and 65 degrees. But even more critical is relative humidity: it needs to be around 50 percent in the middle of the day. What…

When it comes to building a house, one of the first decisions is where to put it. The same is true for birds. It's called "nest site selection." And one thing most birds have in common? The female chooses the site. A robin builds its nest on top of a stout branch. This Warbling Vireo hangs…

All birds lack the typical gene for detecting sweetness, but hummingbirds avidly seek out sugary nectar. It turns out that evolution has transformed hummers’ taste receptors. Mutations to their savory taste receptor gene allowed the receptor to respond to sucrose and other sugars…

A Tufted Titmouse has just about everything you could ask for in a backyard bird. Petite and strikingly elegant, it’s as perky as a chickadee. In fact, it’s a cousin to the chickadee. And as it comes boldly to your seed or suet feeders, the Tufted Titmouse will even hang upside down like…

May is the prime month across much of North America to celebrate the return of migratory birds from the tropics. Of all those coming back, it is the warblers that many birders eagerly await. And of the more than 50 species that brighten our spring, many gleam like precious stones. From the…