Vaux's Swifts

We watched swifts gathering, swirling around and around, and finally disappearing down a large, old school chimney in NW Portland last night from 6:00 to almost 8:00. While the birds numbered in the thousands, there were hundreds and hundreds of people watching.
"Vaux's Swifts are using the Chapman Elementary School chimney as an evening roost during their fall migration. Every year in late August, one of Portland's most spectacular natural events begins: Thousands of Vaux’s Swifts gather in the city as they prepare to migrate to Central America and Venezuela. Migrating swifts often use chimneys as roosts, and they are likely to return to the same roost year after year. One population has been returning to Chapman since the 1980s, and it is one of the largest known roosting sites."