PORTLAND, Ore. (KOIN) — Don’t forget to look up next month. You could miss the Vaux’s Swifts as they pass through Portland during their annual migration.
The birds first arrive in Oregon in April. Later in the fall, large flocks fly back to Central America and Venezuela. However, the species “roosts” in chimneys overnight during their journey — which brings crowds of people to Chapman Elementary for Swift Watch every year.
“[Swifts] used to roost in Old Growth tree snags — so big, hollowed out trees — but there's not too many of those left,” Bird Alliance of Oregon’s Master Naturalist Candace Larson said. “They have adapted to using our old brick chimneys in urban landscapes as some of their bigger roosts.”
She noted these chimneys are also a “little bit of an endangered habit,” hence why the Bird Alliance is pushing for more sites to maintain the habitat for swifts.
That hasn’t stopped the natural phenomenon from occurring around sunset nightly in September, with the flock typically peaking in the middle of the month. The Bird Alliance previously recorded about 10,000 Swifts in a single night.
But weather is one factor that affects how many birds gather, and for how long.
“If the weather turns and we have a cold, wet end of September, the birds will just be done. If we have a long, sort of extended summer around here, sometimes they'll hang out into that first or even the second week of October, but in much smaller numbers,” Bird Alliance’s Master Naturalist Candace Larson told KOIN 6.
Human attendance can also vary, so potential bird-watchers are encouraged to plan ahead — just in case there are thousands of people setting up blankets and chairs for the main event.
Organizers advise attendees to be mindful of the surrounding neighborhood by using public transit or parking a bit farther away from the school.
And after last year’s debacle, the Bird Alliance is also asking visitors not to use drones and disrupt the swift’s migration.
