Makes sense. A tripod could fit in a canoe. And might be helpful in calmer waters.I was thinking the tripod for handsfree use and using the screen rather than the viewfinder especially if just drifting or when boat becomes a floating blind. And good point (also made by a couple others) re too close with the 500/700w1.4 pf, which I experience on land, let alone in a boat meant to get me closer. 180-400 would work, but it's so heavy it'll be awhile before I trust myself enough to put it in the boat. 70-200 will have to come along, as well I'm thinking.
I couldn't use a tripod in my kayak cockpit. And I am not sure a monopod would be all that helpful. I have seen someone who physically attached a tripod to her kayak.