Strange and 'sophisticated' round bite marks on tuna's body, the culprit turned out to be this 'monster'

A tuna caught off the coast of Australia on October 29 had a body full of strange round holes. Jason Moyce - a professional fisherman and tour guide - believes that cigar sharks are the "culprits" responsible for these bites.

The cookie-cutter shark is a small shark known for its precise, marking bites on larger prey. These fish grow to a maximum length of 43 to 56 cm (17 to 22 inches), typically inhabiting deep waters and coming close to the surface at night to feed.

The bite marks are strange round holes on the tuna's body.

They migrate vertically through the water column each day, swimming up more than 3km to feed before diving back down again. Notably, these sharks have been observed to have the ability to bioluminescence, glowing in the dark.

" Unlike wounds caused by squid or sea beetle bites, wounds caused by cigar sharks have a very smooth bite surface, round or oval in shape, characterized by a relatively deep and smooth depression ," says Mark Grace, a fisheries scientist.

The "culprit" that caused the strange bites on the tuna's body.

Cigar sharks feed by attaching their mouths to their prey using suction, then spinning around and using their sharp teeth to 'slice' flesh off the animal. The cuts they leave behind are typically about 5cm wide and 7cm long.

The tuna caught had multiple wounds all over its body. It is likely that it was bitten by several cigar sharks at the same time, and then forced to flee as is normal for other species. These were painful wounds.

Not only on tuna, this small shark also attacks other species including dolphins, sperm whales, fur seals, dugongs, great white sharks, and even stingrays and leaves similar wounds. This is also a shark species capable of reproduction, in addition to "cutting" a little flesh like the case of the "lucky" tuna above, they can also eat prey, with squid and smaller fish.

There has been one case of a cigar shark having prey meat from separate bites found in its stomach, suggesting that it is an omnivore. There have also been attacks on humans. In 2019, a 58-year-old swimmer was bitten by a cigar shark while swimming at night. The man was bitten in the stomach but survived.