Researchers Have A New Theory About Boat Ramming Orcas

Since 2020, juvenile orcas have been intentionally colliding with boats off the coasts of Spain, Portugal, France, and Morocco. The most recent incident occurred off Spain’s northwest coast on August 25, 2024. A pod of killer whales damaged the rudder of a sailboat named the Amidala, leaving its two passengers stranded. While this boat remained afloat, the orcas' attacks have caused at least seven vessels to sink in the past four years.

In May 2024, a team of international researchers attributed the unusual behavior to bored teenagers seeking entertainment. They linked this boredom to the abundance of the Atlantic bluefin tuna, their primary food source. In the past decades, when tuna was scarce, the mammals spent most of their time searching for food. However, now, with plenty of tuna available, the young orcas seemingly had more time to engage in playful activities.

But a new study from the Bottlenose Dolphin Research Institute in Spain asserts that the young orcas are not attacking boats for fun. They are doing it to improve their hunting skills. Bruno Díaz López, the institute’s chief biologist, and his team believe that while there is plenty of tuna, catching them is not easy. The fish can grow up to 10 feet (3 meters) long and weigh hundreds of pounds. They also swim in large groups and move at rapid speeds. The orcas, therefore, must work together to catch their prey. To isolate a single tuna from its group, they take turns ramming into it.

"Maybe one orca hits, and then another one hits again," Díaz López explained.

Once they successfully separate the individual, the orcas pursue and exhaust it. Finally, they guide the weakened fish toward shallower waters, where it becomes easier to catch.

The researchers believe sailboats are ideal for the orcas' training. Like the tuna, the boats move swiftly and quietly, staying close to the water's surface. The orcas repeatedly strike the fast-moving boat and then attempt to bite it, similar to how they would target a tuna.

“This is like a training toy,” Díaz López said. “It’s a shame that we humans are in the middle of this game, but they are learning.”

To minimize encounters, scientists recommend avoiding areas with known orca activity when possible. Additionally, making loud banging sounds around the boat may help deter the whales. Boat owners can also consider modifying their vessels to make them less appealing to orcas. For example, replacing smooth rudder surfaces with bumpy materials could make them less fun for the orcas to "practice" on.

Resources: Livescience.com, CNN.com, Unilad.com