Well, that's rather taking the piss, because river or not it gets VERY dark in jungles because all the ambient light is absorbed, just like in canyons.
But I assumed your camp for the night would NOT be on the river bank as that would be exceedingly stupid; you would have no cover and you would be wet and miserable. And you would also be dead by now.
BTW, you are moving DOWNSTREAM, not up. K'rra Chi is a port; the river flows TOWARDS it.