Last month, Canadian Nuclear Laboratories invited a number of researchers to witness the nightly roosting of chimney swifts in one of their ventilation stacks!  They were kind enough to allow me to film using my thermal camera the gathering of over 1000 birds at ~8:45pm one evening.  Now, if only I can find the time to help with writing code to help them count the birds entering the chimney!  Here is a brief video and a link to CNL’s facebook site:

A similar video, this time a sliding subtraction video, showing the mesmerising flow of birds: