I got a captain's sit in a double kayak this time and had an apprentice to do the rowing for a while to draw. And then just stopped to do several views from the same shady spot in the middle of mangrove maze.
That PowerTank ballpoint pen from uni was amazing! (see photo of the process below). It worked on my completely wet, salty paper like a brush! I loved it so much that I even tried to take it with me scuba diving - but at 70 feet it refused to pump ink :( too bad - it would have been a great tool! But it survived the submersion and depth and my vigorous attempts to use it and still works fine on the surface.