I second what Bigga says about the beautiful scenery of the Morass as seen from the river. Birdwatchers would love it too! I'm really surprised that the boat Captains don't take tourists up the river more often. (I wonder if rafting on the river might be a good business venture?). I'm sure it would be a fun morning / afternoon of fishing on the river. I think you would want a boat with shade. One of my friends told me not everyone will eat fish caught in the river, because of the outflow from the sewage lagoons. (and I have no idea how often untreated sewage goes in the river and out to the sea, but have had some tell me not to go swimming at certain times because you would be taking a sh*t bath)
Brasi, I think a cooler of cold stripes would be required for a river fishing expedition.