I have done a fair bit of canoeing including a backcountry canoeing circuit that is 116 km that can take 4 to 9 days depending on weather and aspiration - we have done this 16 times. I have not been on too many of those trips though with iNaturalist in mind and therefore my photography and iNat obs is a little thin considering how much I have done - I have had a chance to see a lot over the years. The thing with these trips is that for the most part one is trying to travel so fishing and naturalizing to a satisfying level are compromised - hence I don’t fish on these trips but there is occasionally time to pull out the lens when needed.
I now use a DSLR with a long lens (150-600 zoom) - it is a big rig. I take this in my canoe in its own small dry bag which is clipped to a thwart when I am not using it. I have the camera clipped to me via a harness when I am in comfortable waters - and I am wearing a life jacket On rivers, the camera is extra secured to counter any knocking around. I do have a pelican box from the past but my camera has outgrown it. I bought a dry bag in Kuala Lumpur for a primate outing in Sumatra that ended with an inner tube raft through some white water back to our stay - my camera kept dry.
You will need to shoot at a higher speed because of the canoe’s motion - consider cropping rather than being zoomed right in as that will allow you to compensate for an off-centred image without loosing part of the subject because you were too close in visually and the horizon moved - if you can take a burst of shots as well because focusing can be a slight challenge when you are the thing in motion.
Canoes can be very stealthy on lakes and waterways and yes learn to scull. Give yourself an exit if you are approaching large game. You can skirt very close to shore in a canoe. Keep away from deadheads and sweepers if you are on moving water and focus on safety over nature - sort of like bird watching and driving.
Canoes are like having the trunk of a car with you - they were designed to haul big game (I don’t hunt or fish) - so bring along some comfort and sometimes you will want to be on shore. - small light lawn chairs, food, cushion for sitting on rocks if there is no room for chairs, small stove and coffee fixings - tailor this to portages etc. Because of where we go we are always prepared for it to be rainy 100% of the time - most times it is better. I might think of more later.