We visited friends of ours at their home in Constantia for a sunny afternoon outside by the pool. Before you think that this is the pool to which I'm referring - well, no, the pool in the photo is a little garden rock pool filled with frogs, tadpoles, fish and a plethora of other aquatic critters.
From what I can tell, the little fiend that you see in the rock pool is a very young Lycodonomorphus rufulus, also known as the South African Brown Water Snake. We stood and watched the snake come up every five minutes for a breath of air and then descend below the water, behind a couple of rocks.
The last time we watched him descend I'm not sure that it was out of choice - he was being hounded by a small fish that seemed to be nibbling at his tummy. :)