A group of rogue killer whales has been attacking boats off the coast of Spain and Portugal, and it is getting worse and worse, experts said.

Since summer, the sailors have reported that orcas are ramming their boats and sometimes for hours on end. This year, there have been 49 incidents of killer whales attacking the boats recorded, a behavior that was not previously reported.

Scientists are still baffled why these orcas are attacking the boats. Fortunately, no humans have been killed by these unusual interactions with the whales. Spanish authorities have already prohibited boats that are smaller than 49ft from sailing where the reported attacks happened.

Video footage of one of the attacks can be viewed below. This was posted by Halcyon Yachts- International Yacht Delivery on YouTube:

Unusual And Impressive Behavior

Several scientists formed a group to observe the unusual behavior of the killer whales. They discovered that most of the attacks were caused by three young orcas, namely Gladis Black, Gladis White, and Gladis Grey.

They also observed that these orcas suffered from injuries, although they are not sure whether these were from their encounters with the boat or just before the attacks started. Nonetheless, biologist Renaud de Stephanis said that the encounters with these killer whales are getting worse and worse. 

Moreover, marine scientist Ruth Esteban who works at the Madeira Whale Museum in Portugal, said that it seems the orcas are going for the rudder perhaps because it is the only mobile part of the vessel.

She told BBC that in some cases, the killer whales could move the whole boat with it, as seen in some video in which they can move the boat up to 180 degrees. Indeed, it is very impressive for these orcas to move something massive.

Scientists continue to investigate the unusual behavior of these whales. Some say that the "rogue pod," described as marauding teenagers, seek revenge after one of its friends was injured, most probably by a boat. However, scientists have a different explanation.

Read Also: Humpback Whale Tipped Over Kayakers, Almost Swallowing Them

Playing Rogue Whales

The first reported orca attack was in July, wherein a sailing vessel was pushed back to shore when orcas were attacking it and damaged its rudder, while the most recent one was in October.

But scientists do not think that the killer whales wanted to harm the humans onboard the vessels or attack the boats for revenge, Newsweek reported. Instead, they believe that their behavior is related to play.

Renaud said that for so many times that he had seen orcas hunting, these whales always sneak up on their prey and are very aggressive. Their behavior while hunting is contrary to their behavior towards the boats that they are attacking, that is why Renaud believes that these orcas are playing.

"It's mainly two of those guys...that is just going crazy," he said. "They just play, play, and play. And the game is getting worse and worse," Renaud said.

The orcas just seem to love what they are doing, but it is concerning because of the damage it has caused on the boats. Their group is now working with crews of boats to learn more about their experiences. They are also looking out for any sightings of the three orcas.

Read More: Rare Whales That Were Hunted Almost to Extinction Survived Under the Arctic Ice

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