Buzz
The Mola mola, resembling a prehistoric shark that appears to have lost its tail in a fierce battle, is arguably one of the ocean's most bizarre fish. Explore why this marine creature is considered one of the most intriguing in the world.
1. They enjoy soaking up the sun.
Ocean sunfish dedicate nearly half their day to sunbathing near the water's surface, a behavior that helps them regulate their body temperature after diving into colder depths to forage.
2. Their weight can surpass that of an automobile.
Typically, ocean sunfish measure around 10 feet in length and weigh approximately 2200 pounds, though the largest specimens can reach up to 5000 pounds. In comparison, the average pickup truck weighs just 4000 pounds, solidifying their status as the largest bony fish on the planet.
3. They produce more eggs than any other known animal.
Image Credit: Pline via Wikimedia Commons // Public Domain
A single sunfish can release up to 300 million eggs in one spawning event, surpassing the reproductive output of any other vertebrate.
4. Their teeth are extraordinarily unusual.
The teeth of the Mola mola are fused into two plates, resembling the shape of a parrot’s beak.
5. They share a family connection with bass.
The sunfish family includes species like largemouth bass, smallmouth bass, rock bass, and black bass. Bass often prey on smaller relatives within the sunfish family, such as bluegills.
6. Polynesian folklore considers consuming them to bring misfortune.
A massive 3500-pound sunfish was captured off California’s coast in 1910. Image Credit: Library of Congress via Wikimedia Commons // Public Domain
As noted on marine biologist Tierney Thys’ website OceanSunfish.org, Polynesians referred to the sunfish as the “King of Mackerel.” They believed harming sunfish would bring bad luck, fearing it might disrupt the mackerel’s migration to their islands.
7. Their name is inspired by a millstone.
The scientific name Mola mola derives from the Latin term for “millstone,” referencing its gray, circular shape and coarse surface.
8. Germans refer to them as “swimming heads.”
In German, sunfish are called Schwimmender Kopf, translating to “swimming head,” a fitting description of their unique look. Similarly, the Polish name samogłów means “head alone.”
9. They inspired the name of the world’s most beloved sailboat.
The Sunfish sailboat, created in the late 1950s, was envisioned as a sail-equipped surfboard. In 1995, it earned a place in the American Sailboat Hall of Fame as the best-selling fiberglass boat in history.
10. They are capable of diving to depths of 2600 feet.
A sunfish observed near the Galápagos. Image Credit: Edgard Dias Magalhães via Wikimedia Commons // CC BY-SA 3.0
While sunfish typically inhabit depths of 160 to 650 feet, they occasionally venture much deeper. Research has documented a sunfish plunging over 2600 feet beneath the ocean’s surface.
11. They are fierce hunters.
Previously, scientists believed sunfish were passive creatures, spending their time basking in the sun and consuming jellyfish. However, despite their clumsy appearance, sunfish are active hunters with selective preferences, covering several miles daily. Recent studies reveal that sunfish target only the most nutrient-rich parts of jellyfish—such as the gonads and arms—while discarding the less valuable bell. They also supplement their diet with small fish and zooplankton.
12. In 17th-century Japan, they were used as tax payments.
Between the 1600s and 1700s, Japanese shoguns allowed Mola mola to be used as a form of tax payment [PDF].
13. Today, they star in a well-known Japanese video game.
Image Credit: Select Button Inc. via Google Play
A popular mobile game titled Survive! Mola Mola! has garnered over 6 million downloads in Japan. The game focuses on raising an ocean sunfish, akin to a Tamagotchi but for uniquely shaped sea creatures.
14. Their classification as plankton is debated.
Despite their enormous size, sunfish were long categorized as a form of plankton, as they appeared to drift with ocean currents rather than actively swim. (Plankton move with currents, incapable of swimming against them.) However, recent research on Mola mola challenges this notion, revealing that sunfish can navigate independently of currents and achieve speeds comparable to other large fish.
