An abandoned brick chimney of an iconic vintage building in downtown Los Angeles is a somewhat unusual place for Vaux’s swifts to hunker down for the night after a day of air-borne foraging of insects while migrating north, bird experts said.
Naturalists, ornithologists and just plain ol’ bird watchers stood in awe while watching thousands of the small birds dive-bomb into the 12-story chimney of the 84-year-old Chester Building, thought to be one of the most populous roosting places in North America for migrating birds.
“I never dreamed I’d see something like this in the central city,” said Tomas Hernandez, the parking structure attendant where the Vaux’s swifts were being viewed and photographed.
Kimball Garrett, ornithology collections manager of the Natural History Museum of Los Angeles County, said:
“That chimney is a good place for them to sleep. They spend all day feeding on nice hatches of insects blown skyward by updrafts along the Los Angeles River and Elysian Park area. At nightfall, they all come together to roost in the same safe resting area.”
Even two-year-old Avery Van Gundy was rapt with excitement at viewing the spectacle of thousands of birds amassing from all directions and plummeting into the vacant chimney. While shooting off photos with a camera she just learned to use, the precocious tot, exclaimed:
"There's a lot of birds, Mommy!"
Gary George, chapter network director of Audubon California, simply shook his head, smiled and said:
"Just look at them."Vaux’s swifts -- about 4-½ inch long brown birds with white underbellies and long, crescent-shaped wings -- are believed to be at the peak of their northward migration from wintering grounds in Mexico, Garrett said. At winter’s end they head for breeding grounds as far north as Alaska, while others summer in Washington, Oregon and southeastern British Columbia.
Charlie Collins, a retired Cal State Long Beach biology professor and expert on swifts worldwide, said:
“The chimney is only a temporary migratory stopover. They'll be gone within a week or two. But they'll be back at the same chimney during fall migration in September. I'd bet on it."
If they had their ‘druthers,’ swifts would opt for resting in hollowed out old trees. It’s an unsolved mystery as to why they’ve chosen to move to various chimneys over the past 20 years.
The choice of chimneys may be due to loss of natural habitats along with old dead trees.
But soon there may be a shortage of chimneys as well, as many are being torn down, because they don’t meet new earthquake codes.
New industrial and office building chimneys must be made from steel or other metal. The swifts can’t gain a claw-hold, therefore opting for the old concrete and brick structures, Audubon Society members said.
The only down side to nature’s spectacle that began around 7:30 p.m., was swifts being snatched out of the air by hungry ravens that were flying-in-wait for a chance at grabbing an in-flight dinner with their beaks. Perhaps nature’s way of balancing things as both species feast on the fly.
That aspect of the migration event made for some unhappy campers who were viewing it from an adjacent rooftop.
Mary Locuvan, a Los Angeles Audubon spokeswoman, exclaimed:
"It's like watching bears grab salmon out of a river. Where's the 12-gauge shotgun?" "No way!” responded Nicole Possert, “ravens have to eat too."