Now, that's an interesting boating story, but why do I bring it up here? Two reasons, both related to my ongoing effort to bring you the experience of living aboard a sailboat. First, it is the nature of things that when you are asleep on a boat, you are not really completely asleep. A small part of your brain remains on duty, paying attention to those senses which still operate. This ever-alert sentry takes note of unusual motions of the boat and unusual sounds, and presses the alarm bell when something is detected, waking up the rest of the brain. People on shore rarely experience this sleeping awareness, although it is frequently mentioned in detective novels ("Dirk awoke suddenly, fully alert. Something had alerted him, bringing him to full awareness in the blink of an eye. What was it? Then, he heard it again: the quiet sound of a footstep on the stairs.")
And second, living on a boat is akin to living inside a guitar. The mast is the neck, the shrouds and stays are the strings, the hull and deck are the body of the guitar. Anything happening to the rig is greatly magnified down below. A loosely tied 1/8" flag halyard, occasionally bumping into a nearby stay when the wind blows sounds like a maniac pounding on the rigging with a hammer. A bird caught in the rigging? You are not going to sleep thru that.
The story has a happy ending. They were able to untangle the heron and free him to fish another day. And now I should probably go up on deck and see what it is that is tapping against our mast.