28 Dec 2011

A Spectacle of Swifts

With a park ranger husband I have spent most of my life living in natural places rather than cities. A few years ago we lived in Oregon where, twice a year, an amazing natural phenomenon takes place: the Vaux Swifts stop by during their migration north or south. These small birds are amazing aerial artists. Looking like large swallows, they fly quickly, soaring and diving through the sky while catching insects.

Vaux Swifts are migratory birds. In winter they live as far south as Central America and Venezuela in South America. But in the spring they come to the western United States and Canada to lay eggs and raise their babies. During their migration visits, these little birds are an amazing sight. Unfortunately, their presence in Canada has sharply declined in recent years due to loss of habitat. Old brick chimneys are disappearing and, with them, the place where these birds like to hang out.

Vaux Swifts like to spend the night in a chimney where they are safe from predators. In Eugene, Oregon, close to where I lived, is a tall, brick chimney. It is not in use and offers a safe, dark place to spend the night.
When I first get there, toward dusk, there isn’t a bird in sight. But after waiting for some twenty minutes I notice many swifts swarming in the sky overhead. Another ten minutes later, the entire sky is dotted with thousands of tiny birds, diving and dancing, grabbing one last bite to eat before bedtime.

Suddenly the birds start to soar over the chimney opening as if staking out how to get inside. Then they begin to fly in a circular formation. And suddenly, as if on some invisible clue, the first bird dives into the chimney. The others follow. It looks as if someone has turned on a gigantic vacuum cleaner inside the chimney, sucking up all of the birds. Thousands of birds disappear into the brick chimney. Within another ten minutes, not a bird is left in the sky, which the setting sun has now painted dark orange and purple.

Scientists say that the Vaux Swift’s feet are like velcro - they can stick to the brick surface inside the chimney without hanging upside down like bats. The birds also roost in hollow trees. Inside the safe, dark space the birds spend the night. The next morning they will all emerge from their resting place to continue their long trip north or south.

In eastern Canada there are several old brick chimneys left, at campuses, highschools and churches, where you can observe these birds. By mid August the birds will be on their way south, a 10,000 KM journey.
If you ever get the chance, watch the swifts enter or leave their chimney. It’s an amazing sight.

Margriet Ruurs is the author of
27 books for children, including Amazing Animals, In My Backyard and Wild Babies, Tundra.

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