Why do killer whales attack boats near Gibraltar? Scientists finally have an answer

Orcas that lunge at and sink boats in the Strait of Gibraltar could simply be adolescent killer whales playing and following a behavioral pattern, according to a marine biologist.

Since May 2020, researchers have documented nearly 700 incidents of killer whales ramming boats near the Iberian Peninsula.

This behavior has left sailors and scientists perplexed, with many suspecting that the killer whales teach each other to attack boats passing the area.

Theories trying to explain this strange behavior range from food shortages – orcas treating boats as competition for their favorite prey – and the sudden resumption of water activities after the pandemic.

Today, eminent marine biologist Alex Zerbini, chairman of the scientific committee of the International Whaling Commission (IWC) and member of a working group set up by the Spanish and Portuguese governments, says the behavior of killer whales is very probably new. cultural tradition” without an obvious objective.

In other words, orcas could simply be following a new “fashion,” scientists now suspect.

“Different populations often have distinct dietary specializations maintained through cultural transmission, and these 'ecotypes' typically have a variety of persistent behavioral traditions linked to their divergent diets,” explains the marine biologists' paper.

“Some populations may also develop unusual and temporary behavioral 'patterns' and other idiosyncrasies that do not appear to serve an obvious adaptive purpose.”

Researchers highlight several strange behavioral practices observed in orcas at different times over the years.

Citing one example, they claim that South Pacific killer whales developed a habit of carrying dead salmon on their heads in 1987, a habit that began with younger individuals and spread throughout the population without serving any purpose. obvious ending.

This behavior “disappeared shortly thereafter,” only to reappear in the summer of 2008 and disappear once again.

In another case of strange behavior that has come and gone in the span of 20 years, pairs of adolescent and adult male orcas have been documented exhibiting ritual headbutting or headbutting.

In recent incidents, most killer whales that approached damaged or sunken ships were juveniles that usually approached slowly, as if trying to gently bump the rudders with their snouts.

“There is nothing in the behavior of the animals that suggests they are aggressive,” Dr. Zerbini said. The Washington Post.

“Not all interactions resulted in damage to the vessels,” the scientists stressed.

Researchers suspect that this new behavior in orcas may disappear at some point and reappear later.

“When they play with the rudder, they don't understand that they can damage it and that damaging it will affect human beings. It’s more playful than intentional,” Dr. Zerbini said.

“It may be that the current fixation of Iberian killer whales on boats, and particularly on their rudders, is such a fleeting fad and that, if it suddenly ceases, it could reappear later.”