It appears that the vicious south-easter winds of the past week are to blame for the stranding of a number of Slender Sunfish along our western shore from Scarbourough to Melkbos. According to Two Oceans Aquarium Curator Michael Farquhar, “The strong southeasterly winds result in upwellings of icy cold water off our west coast. The Slender Sunfish are a tropical species preferring warmer conditions and were probably trapped inshore as a result of the wind and then succumbed in the cold water.”
The Two Oceans Aquarium has put out a request to the public to phone 021 418 3823 in the event that they encounter a live Sunfish on the beach or in shallow water. Slender Sunfish (Ranzania laevis) are rare and little is known about these beautiful animals. For this reason “the Two Oceans Aquarium is keen to display one so that people have the opportunity to see them from an underwater perspective,” said Farquhar.
Penelopy Cheney of the TMNP (see photo to the left) alerted me to reports of numerous Sunfish washing up on Long Beach, Kommetjie and invited me to join two TMNP officers on a patrol of the area. We found 12 dead Sunfish and a large shark beached along the line of the spring high tide. The dead shark, which appeared in prime condition, was subsequently identified as a Carcharhinus limbatus (Black Tip Shark) by shark expert Leonard Compagno of the AfriOcean Conservation Alliance. He commented that the shark, a big adult male, was a surprise for him as although Black Tip Sharks are common, they are not usually not found south of Congo or the Eastern Cape. He believes that like the Sunfish it was possibly stunned and killed by upwelling after traveling on a warm water mass during an exceptionally hot summer.
Watch this post for more feedback from the experts. Is there a connection between the simultaneous stranding of the Sunfish and the +2.2m Black Tip Shark, which both prefer tropical seas?
Is the stranding of these animals part of a natural cycle or are they victims of Climate Change and have been swept too close to foreign shores by quirky currents? A number of specialists are investigating and will hopefully be able to provide some answers. What do you think – have any of you seen Slender Sunfish off Cape Point or the West Coast before?
Sunfish are enigmatic fish and feature in the folklore of fishermen around the globe. In South Africa, fishermen say that when the sunfish come inshore, their presence is a warning that a storm is brewing at sea. They are known by a number of names, the word Mola comes from Latin and means millstone–in reference to these fishes’ roundish shape. The common name “ocean sunfish” comes from the Mola mola’s habit of lying near the surface of the ocean appearing to sunbathe. Other names include: Rompvis (trunkfish), Poisson Lune (French for “moon fish”), Schwimmender Kopf (meaning “swimming head”) Putol (Philippine for “cut short”) Toppled car fish (Taiwan) etc.
There are three genera of Sunfish with 4 to 5 species all of which are related to the boxfish, porcupine fish and puffers. The family resemblance can be seen in the juvenile form of the sunfish before they loose their spiky skin, their body truncates and they grow huge.
The Southern Mola (Mola Ramsayi) or Sunfish is a fairly common visitor to our coast. They feed off jellyfish and bluebottles. Their habit of wallowing on the surface, a large dark mass with a prominent dorsal fin, is the cause of heart stopping moments for ocean paddlers. These moments of shark-fright are often followed by an exaggerated hilarity bourne on waves of relief and amazement at the Mola’s comical shape. It has a truncated body which is little more than a large head equipped with long sweeping fins atop and below. Mola mola presently hold the record for the world’s heaviest bony fish. A 3.1m long specimen weighed in at 2235 kg (Carwardine, 1995).
The Slender Sunfish such as those that washed up between Kommetjie and Noordhoek, is the baby in the family, not exceeding 80cm in length. They eat plantonic crustaceans and typically occur in warmer oceans around the world. Very little is known about them and there are conflicting reports about their distribution off the coast of South Africa. For more information about Sunfish and to report sightings go to www.oceansunfish.org
With thanks to Danielle Bowen and Sylvester Ohlsson of TMNP, Marine Protection Division for their company and for some insight into their work.