One thing that hasn't been mentionned that I carry in my gear is a pen flare with flares & bear bangers (at least 3 red, 3 green flares & 3 bear bangers). The air horn is also a very good idea. I find that canoeing on a busy waterway is unnerving because many boaters don't look where they're going, so make yourself & your canoe as visible as you can. Consider a flag, perhaps like a Bike flag on a 6' lightweight pole, if you find that motor boats get too close.