A recording of our most recent talk is up on YouTube from our excellent speaker George Candelin, Keeper of the Swifts at Oxford University Natural History Museum, on 30 Years in the Tower recording swifts.
youtu.be/2n7p4s3LUSI?...
youtu.be
30 Years in the Tower: George Candelin, Keeper of the Swifts at Oxford University
YouTube video by British Ornithologists' Club