Marine biologist Tierney Thys and researchers at the Monterey Bay Aquarium are learning more about one of the largest jellyfish eaters in the sea.
Part of the appeal of the ocean sunfish, or Mola mola, is its unusual shape. The heaviest bony fish in the world, it can grow more than 10 feet long and pack on a whopping 5,000 pounds, and yet its flat body, which is taller than it is long, has no real tail to speak of. (“Mola” means “millstone” in Latin and refers to the fish’s disc-like physique.) To motor along, the fish uses powerful dorsal and anal fins.
The mola is something of a star at the Monterey Bay Aquarium, the only facility in North America to currently exhibit the bizarre-looking fish. “You just don’t see anything like that,” says John O’Sullivan, a senior collector at the aquarium. When the nearly four-foot-long sunfish swims slowly across the two-story window of the Open Sea gallery, its large eyes pivoting as it travels, it is as if the whole building shifts with the weight of people gathering in awe, he says.
For being so visually arresting (it is on the bucket list of many scuba divers), the mola is a bit of a mystery; very little is known about its biology and behavior. Tierney Thys, for one, is trying to change this.