Having been looking into black grouse lekking behaviour over the past two months, I was surprised this morning to watch a blackcock fall fast asleep with his feathers at full lek arrangement. He had been patrolling through some marshy ground, and came to a halt after half an hour. He pulled his head into his shoulders, yawned mightily, then started to blink for longer and longer periods. After opening and closing his eyes for some time, he closed them altogether for three or four minutes. What was surprising was that during his nap, his tail never sagged at all, and his wattles remained at a constant level of inflation.
When he opened his eyes again, he looked rather embarrassed, like a commuter who accidentally falls asleep on a train and wakes up with his head on the shoulder of a fellow passenger. He sleeked his feathers down, stretched a wing, then wandered aimlessly off into the undergrowth.