I heard this story a few months ago from Benjamin Mitchell, it is good and I wanted to believe it so I did. (Benjamin by the way tells it with a good deal more embellishment.)
Anyone who has had a course from me in the last six months has probably heard me retell the story with a large health warning saying “I’ve heard this story, I believe it but I don’t have a source to prove it.”
Now, Toby Parkins has tracked down the link. So here it is: Parrot cages, the true story, care of the BBC - so it must be true!