The slender sunfish (Ranzania laevis) is a rare species of sunfish found in tropical seas the world over. Its maximum size, unlike its cousin the locally found ocean sunfish (Mola mola, which can be 3 metres across) is about 1 metre.
I saw this specimen swimming enthusiastic rings in the water in Hout Bay, late in December. He looked as if he was showing off for us. Unfortunately he probably arrived in the cold water here after getting caught in an eddy of the Benguela current, and swept off course into water that is too cold for him. The cold water will get to him eventually and he will probably die.
There have, in fact, been recent reports of these sunfish washing up on beaches and seen dead at some local dive sites – this seems to happen almost annually in summer, as these articles demonstrate (the last link is particularly interesting).
It’s very sad, but part of an entirely natural process. We often see warm water refugees and creatures from far afield in False Bay and around the peninsula – we’ve spotted flutemouth at Long Beach, and a john dory there too. The Two Oceans Aquarium sometimes rescues turtles from the warm KZN waters that have somehow gotten lost and ended up on a beach in Cape Town! Furthermore, many marine animals beach themselves at the end of their lives. Sometimes it’s because of a man-made problem, but sometimes it’s just the end of the animal’s life and how they choose to finish things.
I felt very lucky to see this guy alive and so sprightly. Slender sunfish truly are beautiful creatures.