A crowd gathers as darkness falls outside Chapman Elementary School in Portland, Oregon. The people sit down on a patchwork of blankets and look up. At first, they appear to be staring at nothing but a tall, brick chimney. Then a bird darts into view. Minutes later, thousands of the birds swoop and swirl around the chimney. The avian aerialists, four-inch migrators called Vaux (rhymes with “hawks”) swifts, move from Canada to Mexico every year. You can think of the brick chimney as one of their go-to hotels.
Vaux swifts spend almost their entire lives in flight. They can fly for about 100 miles at a time. But unlike many birds, swifts can’t perch. They have to cling to walls instead. So when swifts do stop to rest, they need very specific lodging—hollow trees, caves, or the vertical walls inside old chimneys. They roost in large numbers in tight, enclosed spaces because their body temperature drops at night.
But chimney “bird hotels” are disappearing fast. The decades-old smoke stacks the birds have adopted are being torn down as people redevelop property. People also destroy the chimneys out of fear that shifting land or earthquakes could make them a hazard. City-dwellers remove the structures because they dislike the dung and noise of the swifts they attract. As chimneys disappear, so do the visiting birds—and no one is sure where they go instead.
The swifts' noisy stopover each fall has become a tradition to Portlanders and even to bird lovers as far away as Europe. But now fewer birds than ever are showing up. Destruction of forests already harms the Vaux swift population. Some scientists think the missing chimneys put the birds in danger too.
The city of Portland is working with the Audubon Society to attract the birds to a 30-foot-tall replacement tower. Conservationists have really laid out the welcome mat for the displaced birds: They broadcast the swift call at 1,100 watts and have smeared swift guano (dung) inside the tower.
"It might be you have to just get the first one to try it and say, 'Hey guys! It's good in here,'" says Joel Geier, an Audubon Society volunteer bird counter. But so far, not a single Vaux swift has checked in.
