Discovery of a record bony fish weighing 3 tons
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A giant sunfish believed to be the heaviest bony fish in the world has been discovered in the Azores archipelago, Portugal, weighing 2,744 kilograms (3 tons).
Researchers said the animal was found dead, floating near the island of Faial in the central North Atlantic in December.
Although discovered last year, details of the find were only recently published in the Journal of Fish Biology.
Studied by researchers from the Atlantic Naturalist Association and the University of the Azores for biometric and morphological data, both in Portugal, the fish was pulled to shore where the animal was weighed, measured and samples of tissues were removed for DNA testing.
There are approximately 29,000 species of bony fish, which have a skeletal bone structure, making them the majority of fish species in the world.
The carcass weighs more than 400 kilograms (882 pounds) heavier than the previous world record holder for the heaviest bony fish – a 2,300 kilogram (5,070 pound) female giant sunfish caught off Kamogawa in Japan in 1996.
The sunfish was weighed with a crane dynamometer – a device designed to weigh loads typically hoisted by a crane – after being lifted above the ground using a forklift.
The animal was 3.25 meters (10.67 ft) long and had a height of 3.59 meters (11.78 ft). Measured around its center (middle of the body), it had a maximum width of 86 centimeters (2.82 feet), the researchers said. The sex has not been determined.
José Nuno Gomes-Pereira, lead author of the paper and postdoctoral researcher with the Atlantic Naturalist Association, told CNN on Tuesday that it was saddening « to see the animal in this situation because it had to be a king of the open ocean ».
The « extremely large » sunfish was buried in Faial Island Nature Park, he added.
Gomes-Pereira said the discovery was a « sign that the oceans are still healthy enough to support the heaviest species in existence, but a warning for more conservation in terms of pollution and boat traffic near ocean islands ». .
The giant sunfish (Mola alexandrini) was first recognized as its own species in 2018 and is known to weigh twice as much as the second heaviest species of fish, the sea sunfish (Mola mola) , according to a press release from the Atlantic Naturalist Association last Thursday. .
Gomes-Pereira said the dead sunfish had a « bruise » – a bruise – on the front, which may have caused the death of the animal. However, it is unclear whether the impact was pre-mortem or post-mortem. The wound was encrusted with a red paint normally used to coat the keels of boats, the newspaper report adds.
With little data available on large specimens such as sunfish, researchers believe further study is needed to understand their physiology and marine ecosystems in general.
The heaviest species of fish in the world is the whale shark (Rhincodon typus), according to Guinness World Records, the heaviest found in Pakistan in 1949, weighing 21.5 metric tons.