Each September, thousands of migrating Vaux’s Swifts use Portland’s Chapman Elementary School’s chimney as their nightly roost before continuing their journey to southern Central America and parts of Venezuela. It’s one of those unique, weird Portland things that you have to see to appreciate. When we moved to Austin years ago, we were not aware of a similar phenomenon with the Congress Avenue Bridge bats, and were surprised to see a cloud of what we thought was smoke in the evening sky. As we got closer, we realized that it was a “colony” of bats in the sky making their way to overnight feeding from underneath the bridge. Admittedly, we didn’t even know at that time that a group of bats was called a colony, but by the time we left Austin we knew everything about bats and other oddities that “Keep Austin Weird” (See Post #109). We hope to know everything about swifts and Northwest weirdness before we leave Portland.
Last night, we planned to watch the swifts in action, but there were thousands of people with the same plan in mind and no parking spots to be found. We did manage to get a great first view by doing a slow drive-by in the car. Just like the bats, they form a cloud in the sky, but funnel like a tornado into the school’s smokestack. They’re on an opposite schedule from the bats, who hunt at night, so as the Austin bats leave the Congress Street Bridge each evening, the swifts of Portland come in for a landing. Apparently, the swifts use this particular chimney as a substitute for scarce hollow tree trunks called “snags,” and make nests of twigs pasted together with saliva in the crevices of the brick. The Austin bats were equally inventive with man-made structures, discovering that the crevices under this specific bridge were ideal for roosting.
Vaux’s swifts are very efficient birds, who even bathe in flight by flying low over a body of water, touching the water with their chest and then shaking the water from their feathers. A group of swifts are collectively known as a “box”, “flock”, “screaming frenzy”, and “swoop” of swifts. They are often described as “fast-flying cigars with wings.” We noticed a “swoop” of them downtown the other night that must have found a similar chimney to meet their nesting needs. I assume that there’s also a time each morning when they leave their nests for the day. I discovered this in Austin on a dark early morning run near the bridge when I was surprised by a colony of returning bats that began to dive-bomb me. I had horrible visions of Dracula. With all the local hype of them leaving each night, nothing was ever mentioned about their early morning ritual of getting back in their little roosting coffins before the sun comes up. I’ll have to learn more about the early-morning habits of the swifts.
In a way, I was glad we stayed in the car last night. As is always the case with large groups of birds, droppings can become an issue. Nothing destroys outdoor enjoyment like bird poop. Whether it’s bats or swifts in large quantities, watch where you step and wear eye protection. Both swifts and bats also make weird noises that echo from the chimneys and bridges that they inhabit, and although neither are particularly dangerous, prepare to have that Alfred Hitchcock’s “The Birds” moment. In each case, it’s an awesome visual experience and a unique encounter with the weird wonders of nature.
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