PORTLAND, Ore. — The swifts are back.

Following a 30-year migration pattern, the Vaux’s Swifts are once again roosting in the chimney at Chapman Elementary School in Northwest Portland.

Every September, thousands of people fill the hillside around Chapman Elementary to watch the swifts swirl overhead, then descend into the chimney at sunset.

The school decommissioned the old smokestack years ago, but with the community's help, the school has preserved the chimney and even earthquake-proofed it.

"My greatest joy is telling people why the birds migrate and getting them excited about natural phenomenon and migration," said Portland Audubon Executive Director Nick Hardigg.

VIDEO: Chapman Swifts (Oregon Zoo)

Hardigg said the swifts began roosting in the Chapman chimney in the late 1980s, using it as a sleeping spot on their way to Central America. He said it's one of the largest known roosting sites of migrating Vaux’s Swifts.

Those interested in watching the swifts roost should visit Chapman Elementary School about an hour before sunset any night in September.

Guests should not expect to find street parking near the school. Instead, they're invited to park for free at Montgomery Park, which is six blocks away at 2701 Northwest Vaughn Street. Parking at SELCO Community Credit Union at 2465 Northwest Thurman Street is also available each night after 6 p.m.

Check out Portland Audubon for more information about the swifts.

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