Across North America chimney swifts (Chaetura pelagica) and their look-alike western cousins, Vaux's swifts (Chaetura vauxi), are migrating south for the winter.
Swifts eat flying insects so they migrate during the day when the insects are out. On hot days they circle high, coursing back and forth in the clouds of bugs. It doesn't look like organized migration but they're tending ever southward while they eat.
At dusk the swifts gather at big chimneys, circle in a vortex, then pop into the chimneys to roost, as shown in the video. On cold rainy days they roost during the day to conserve energy when the bugs don't fly.
Vaux's swifts are on their way to Central America but the chimney swifts will go much further, crossing the Gulf of Mexico to spend the winter in Columbia, Peru, Ecuador and western Brazil. I wonder if their over-water migration gave them the species name "pelagica."
For the next several weeks, watch chimneys at dusk to see the swifts. Click here for suggested sites in Pittsburgh.
Peripatetic: adjective  traveling from place to place, especially working or based in various places for relatively short periods. (definition from Google search)
Hope (69/Z, black/green) is a peripatetic peregrine falcon. For five years she called the Tarentum Bridge her home until last spring when she nested at the Cathedral of Learning.
In my experience, peregrines stay put when they've claimed a prime territory but Hope does not. On Friday she flew 15 miles back to Tarentum and set up shop for several days.
She's so comfortable at Tarentum that, unlike her habits at Pitt, she perches in easy view.
Last weekend Tony Bruno and Steve Gosser stopped by for some great photographs. Above, Tony got a photo of Hope's bands while she was preening. Look how close she is!
Below, Steve caught the action when a curious mourning dove came close while Hope was eating. The dove escaped.
Apparently three days were long enough at Tarentum because Hope flew back to the Cathedral of Learning yesterday afternoon. She appeared on the falconcam at 3:30pm, dug a little at the scrape and then perched and preened.
You can see her band colors below. Her greenish right-leg band and black/green left-leg band are a diagnostic combination.
And here's her familiar face.
She probably was at the Cathedral of Learning during last night's terrific thunderstorm, but who knows.
Hope doesn't perch in sight at Pitt so I'm never sure if this peripatetic bird is actually there.