KayakingAfter the frequent attempts at Bribery, beatings, and simply getting towed at Sunrise - S-B opens the Kayak Forums
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Someone put together a list of kayak colors from easiest to see to most difficult. For whatever reason, red was on the difficult end. Good thing you were there.
He was too far away to be sure but I assume he capsized and couldn't get back on/in. I'm convinced if he was waving a red flare that first boater would have noticed him. A whistle is a good idea but I'm not sure it can be heard over a 2 stroke outboard.
He was in thw water before the boat drove pst him. The point I was making was that a flare would have mde him much more visible to that boater, who drove past him twice without seeing or hearing him.