The Two Oceans Aquarium has received a number of calls from concerned citizens regarding slender sunfish washing ashore around the Cape Peninsula. Sightings of these animals, both dead and alive, have been reported on beaches and in shallow water off Blouberg, Melkbos and Noordhoek.
According to Two Oceans Aquarium Curator Michael Farquhar, “The strong south-easterly winds we have been experiencing recently result in upwellings of icy cold water off our west coast. Slender sunfish are a tropical species and prefer temperate conditions. The reason for them washing ashore is probably because they are trapped inshore and cannot function in the cold water.”
At 80cm in length, the slender sunfish (Ranzania laevis) is a small animal compared to the giant ocean sunfish (Mola mola), which attains a size of 3m. The slender sunfish has smooth skin, as opposed to the sandpaper-like skin of the ocean sunfish.
According to Ocean Sunfish.org, “The Polynesians called these sunfish the King of the Mackerels. It was seen as bad luck to catch and kill Ranzania, for such an act would render the mackerel incapable of finding their way to the islands.
“While ocean sunfish and sharptail sunfish (Masturus lanceolatus) are relatively common in our waters at certain times of the year, slender sunfish are rare and little is known about them. Many people had never heard of sunfishes, let alone seen one, until we displayed a sunfish in the I&J Predator Exhibit just after the Aquarium opened in 1995. At sea you normally only catch a fleeting glimpse of a fin or a large flat disk before the fish dives into the ocean depths – as a result many people mistake sunfish for sharks.”