BirdNote

Autumn … and geese fly high overhead in V-formation. But what about that V-formation, angling outward through the sky? This phenomenon – a kind of synchronized, aerial tailgating – marks the flight of flocks of larger birds, like geese or pelicans.

During the last ice age, a lobe of the ice sheet covering western Canada dammed the Clark Fork River, creating a vast lake in what is now northwestern Montana.

Join members of the Klamath Bird Observatory in Ashland, Oregon, as they head east over the Cascade Mountains and drop down into the Great Basin. They're looking in particular for diurnal raptors, that is, eagles, hawks, harriers, vultures, and falcons that soar and hunt during the day.

Some ducks don't sound like ducks at all. Some, like the Harlequin, squeak. Harlequins are unique in other ways, too. Quick and agile in rushing white water, they dive to the bottom of mountain streams for food, and use fast-flowing rivers for breeding.

Birding guides Victor Emanuel and Barry Lyon explore an old-growth forest with teenagers attending their camp for young naturalists. They study not only birds but also the habitats that support them.

October is the perfect time to plant for the benefit of next year's birds, including this Cedar Waxwing. Your new plants will put their resources into their roots rather than leaves or flowers. And the season's reliable rain will reduce the need to water.

How will birds and other wildlife respond to global climate change? We can learn many lessons from the Alexander Archipelago, a chain of islands in southeast Alaska. Less than 10,000 years ago, these islands were covered by ice.

As Christopher Columbus neared land in 1492, clues in the form of birds gave him hope that landfall was not far off. From his journal, Sept. 14: The crew of the Nina stated that they had seen [a type of tern] which never goes farther than twenty-five leagues from the land. ... Sept.

Waterfowl must swallow hard particles so their gizzards can grind up hard foods, like grains. Unfortunately, they can't tell a lead pellet from a small pebble. Beginning in 1991, waterfowl hunters were required to switch from lead shotgun pellets to pellets made of non-toxic metals.

Shorebirds' lives take them to many places other than the shore. Most of the shorebirds we see along our coasts migrate to the Arctic in summer. Here, many nest on the tundra, some along rushing streams, and others on rocky mountainsides.

The begging calls of male baby Chipping Sparrows mix into what is known as "subsong," a sort of infant babbling. And, very quickly, subsong begins to change to imitations of adult songs.

Right now, volunteer observers are counting shorebirds on the move. Sandpipers, dowitchers, plovers, Dunlin, and others that raised their young in the Arctic are now making southbound migrations. They're looking for places to feed and rest along the way.

Through all of spring and summer, swallows dart and sail overhead, their airborne grace a wonder to behold. But by October, the skies seem empty. Most swallows have flown south, in search of insects.

Henry David Thoreau wrote, "Our little mountain-ash is all alive with [birds.] A dozen robins on it at once ... plucking the berries...

Why is birdwatching so rewarding? Bird guide, Harry Fuller, says it's about three things: It's free. You can do it wherever you are. And it's fun! Once you start watching, you really appreciate the beauty, the complexity, and the wonder of what's going on in the world around you.