Researchers are investigating a string of swordfish attacks on sharks that goes back for numerous years.
The most recent attack was on a 15-foot adult thresher shark that washed up on the shores of Libya in April. During an autopsy on the shark, researchers found a wood-like substance penetrating the fish and embedding near its heart. A thresher shark is known for its long trail that it can whip and stun prey.
The substance that was found inside the shark belonged to the sword of a swordfish.
Swordfish have been known to kill sharks in the past, but the question is if they are deliberate attacks or if the shark was an unlucky victim to the swordfish going after smaller prey.
In the past, whalers and fishers saw swordfish as murderous fish armed with a sharp spear. But in today’s day and age, researchers are skeptical.
However, in September of 2016, an eight-foot blue shark in Spain was dead. The same wood-like piece was pulled from its head and has stabbed the unlucky shark in the brain.
Since the attack in 2016, at least six more sharks have washed ashore along the Mediterranean coasts with stab wounds. Almost all of the fatal blows were in the head of the sharks.
“I thought it was crazy,” said Jaime Penadés-Suay, a graduate student at the University of Valencia and a founder of LAMNA, a Spanish consortium that studies sharks. “I was never sure if this was some kind of joke.”
Shark Vs Swordfish
These cases may be evidence of head to head battles (literally) between the two predators. Another reason may be that some sharks prey on smaller swordfish, so it could be an act of self-defense.
In addition, they might be more common than researchers think, with most corpses sinking to the bottom of the ocean before being found by officials or fishers.
“Now, at least we have evidence that they might use it really as a weapon, intentionally,” said Patrick Jambura, a graduate student at the University of Vienna.
A swordfish can break off their sword without killing itself, although they do help improve speed and hunting abilities. They also do not grow back.
[H/T New York Times]