Thousands of birds enter L.A. chimney, Alfred Hitchcock style

In a scene reminiscent of Alfred Hitchcock’s movie thriller “The Birds,” thousands upon thousands of birds called Vaux Swifts have been using an unused chimney on the roof of the Chester Williams Building in downtown Los Angeles as a nightly roost on their southern migration.

Audubon California reported that the phenomenon happens at dusk and birdwatchers and other on-lookers have been viewing the incredible sight from the roof of a nearby parking garage. “When a couple of birds finally take the plunge, the rest of the flock literally pours down the chimney and disappears for the night,” the report said

“This is one of the more amazing things you’ll ever see in nature–and it’s all the more amazing because it’s taking place in one of the most urban environments in California,” said Jeff Chapman, director of the Audubon Center at Debs Park in L.A.

From Audubon California:

Vaux’s Swifts are small, cigar-shaped birds that migrate south in huge flocks, often roosting in old chimneys and hollowed out trees along the way. A few years ago, the swifts began using an unused chimney on the roof of the Chester Williams Building on the corner of 5th and Broadway.

Daniela Ogden of Audubon California told GrindTV Outdoor that the birds had been using a similar chimney in San Rafael, California, too. She added that the birds were still flocking to the Los Angeles-area chimney this week, though the numbers haven’t been quite as dramatic.

Fortunately, Audubon California posted a video of the eerie scene on YouTube a few days ago. Watch as thousands of Vaux Swifts swirl around the opening of the chimney before descending into their roost like water draining down a sink:

Photo credit: Martha Benedict