There may be no busier bird during the nesting season than a male House Wren. Just a day or so after completing his spring migration from the tropics, the male House Wren claims a territory and checks out several potential nest cavities. And in each of these locations, he builds a starter…

Each spring, millions of birds head north. From Ecuador, beautiful Scarlet Tanagers fly to the eastern US and Canada, many traversing the Gulf of Mexico, an arduous journey. Across much of southern Europe, Common Nightingales – small thrushes with russet feathers – are arriving, having…

One of the most musical and complex bird songs in the US is that of the Brewer's Sparrow. It's a veritable aria, ringing forth from the sagebrush of Eastern Washington's Columbia Basin. Shrub-steppe is disappearing from the interior west as it is cleared for irrigated crops. The…

Female birds need to eat calcium to have enough of the mineral to lay their eggs. But it can be hard to find enough of it to eat in nature. We can help our backyard birds by offering them some extra calcium in bird feeders and by recycling our used egg shells. This show brought to you by…

The Ruby-crowned Kinglet is one of the smallest songbirds on the continent, weighing in at just a little more than half a chickadee. Mostly green and hard to spot, it hovers in mid-air as it catches tiny insects. In early spring, the kinglet's rollicking song echoes from the forest edge in…

Want to try building a nest? Consider this... An average American Robin weighs less than three ounces. An average person weighs 170 pounds, or 1,000 times as much as a robin. A robin's nest, made of grass and mud, weighs about seven ounces, so yours will weigh 450 pounds. You'll need to…

If you live in the U.S., parrots might seem like ambassadors from far-off rainforests. Especially since the Carolina Parakeet, a native species once common in the South and Midwest, went extinct in the early 20th Century. But more and more parrots are finding a home here. Since the 1960s…

Scientists have long thought that new species took a very long time to emerge. This thinking has now changed dramatically. On an island in the Galápagos, researchers Rosemary and Peter Grant discovered that a hybrid union of two distinct species of finch produced descendants different from…

Springtime in the Anza-Borrego Desert State Park in southeastern California. Cacti and wildflowers glisten with raindrops, and birds begin to sing. A House Finch, a Bewick's Wren, a Cactus Wren, a Mourning Dove, and this Costa's Hummingbird all add their sounds. The soundscapes featured in…

When glaciers pushed south into what is now the U.S. around 20,000 years ago, they scraped off the soil layer and spelled the end of native earthworms except in the southern states. So the earthworm plucked by the robin in the park or on your lawn is probably a relatively new arrival, most…