The vaux’s swift is found mainly on the west of North America, measuring around 4.5″ around this time of year they can be found in mass flocks at night as they gather to roost. The swift has found an ideal roosting spot in man made chimneys,Monroe WA has just that, you can get over 26,000 of these birds roosting in the chimney on occasions all tightly snugged together. These birds are on their migratory path to Central America and Venezuela and stop off on the way here in Monroe. The sound and video that follows are from the night of September 12th, The night was partly cloudy and cool but it still brought out a sizable flock for us to witness.
Thank you to Kevin Mack for the picture and Pilchuck Audubon for the use of some video in the chimney.
The following audio can be listened to by clicking your mouse anywhere along the wave player, select any area on the player with your mouse.
Vaux swifts monroe
Description: the migration of vaux swifts roosting in a chimney stack
Recorder: SD 788t
Mics: sennheiser mkh 40/30-Telinga DAT
Sample rate: 44.1k 24 bit
Microphone pattern: MS stereo
Anthrophony: constant traffic
Biophony: Vaux swift
Recordist: Martyn Stewart
Notes: inserted -30 db tone at beginning of the recording/ Mic suspension with Rycote windjammer and gitzo tripod/