The wheel was ripped from the crew’s hands without warning, a hard jolt from below, and then the stern swung free.
That moment off Galicia has repeated, with almost mechanical regularity, hundreds of times since 2020.
A group of orcas has developed a habit nobody saw coming: circling sailing yachts from behind, striking the rudder, and holding on until it breaks.
What makes it stranger still is who is doing it, and how few of them there are.
What the orcas are actually doing to the rudder
Maritime authorities on both sides of the Iberian Peninsula have watched a precise pattern emerge: orcas approaching from astern, focusing on rudders, and working in small groups as if on a shared task. The target is never random. According to the Atlantic Orca Working Group, which monitors the Iberian killer whale population, the orcas know exactly what rudders are. “Orcas don’t confuse the rudder with anything,” researchers write. “The speed of the ship and the resistance of the rudder cause it to persist in action.”
The physical sequence is grimly consistent. Orcas strike rudders head on, using their massive heads to crack composite materials, then follow with tail slaps or body rolls. The behavior typically lasts under 30 minutes but occasionally extends to two hours, with juveniles and young adults leading the effort.
In almost every case the orcas swim off once the rudder breaks, with no apparent attempt to sink the boat. The result is a drifting hull, a crew on the radio, and a coast guard launch racing out from the nearest port.
A 65 foot yacht and the waters near Gibraltar
One of the best documented cases involved a 65 foot vessel sailing under a UK flag in the Strait of Gibraltar. Killer whales repeatedly rammed her, rendering the rudder inoperative and cracking the hull. Spanish rescuers had to pump out seawater before towing her to safety, deploying both a helicopter and a dedicated rescue boat for a single drifting yacht.
On August 21 of last year, orcas tore the rudder off a German sailboat in the Vigo estuary, then continued ramming the boat as it was towed toward port. The Spanish Civil Guard shared video from a patrol vessel that had to put its bow between the orcas and the stricken boat. The footage circulated widely among sailing communities.
Even a racing yacht at full speed offered no escape. Skipper Jelmer van Beek called it a “scary moment” when orcas struck during a passage through the Strait of Gibraltar. “Three orcas came straight at us and started hitting the rudders,” he said.
The numbers that define five summers of strikes
Approximately 700 orca interactions have been recorded since 2020, according to reports compiled by the Cruising Association based on data from the Atlantic Orca Working Group. Encounters peaked in 2023 with 207 recorded that year, dropping to 136 in 2024. Almost 20 percent caused enough damage to disable the vessels, says orca researcher Alfredo López.
Yet the animal doing the damage is, by any measure, vanishingly rare. The Iberian orca subpopulation is critically endangered, with only 39 animals counted in the last full census. Of those, just 15 individuals have been identified through photographs as responsible for the damaging encounters.
So 15 animals, out of fewer than 40, have produced roughly 700 coast guard calls and international maritime advisories. “It is a rare behavior that has only been detected in this part of the world,” López says. Researchers note the drop in 2024 may partly reflect sailors changing their routes, not the orcas giving up.
How a fad spreads through a whale pod
The leading scientific explanation is not aggression but something closer to cultural transmission. Social learning drives the phenomenon, similar to fads in other orca populations involving pod specific dialects or food preferences. Once one young animal finds the spinning rudder irresistible, others watch and copy.
One explanation posits that the behavior may have originated from a single orca after a traumatic collision with a vessel, with the habit spreading through imitation. Most researchers favor cultural spread as the more plausible mechanism, dismissing pure revenge as an adequate explanation.
That framing matters for the orcas themselves. The Iberian subpopulation follows Atlantic bluefin tuna on a migration route that puts its members in close contact with fishing vessels and recreational boating. These rudder striking animals are among the rarest ocean travelers on the planet, and their critically endangered status makes every individual count.
What sailors can do, and what remains open
The most counterintuitive piece of official guidance is also the hardest to follow when a dorsal fin appears off the stern. The Atlantic Orca Working Group recommends stopping the ship, cutting the engine and letting go of the rudder. A stationary, unresponsive rudder is a far less interesting toy to an orca than one spinning under load.
Spanish authorities have also advised sailors to stick to shallow waters of 65 feet or less in orca hotspots, or avoid the areas entirely where possible. The waters the orcas patrol run from the open Atlantic all the way into the Strait of Gibraltar, covering hundreds of miles of coastline.
What no one has settled is whether the behavior will fade, spread to other pods, or become a permanent feature of Iberian sailing. Record numbers of attacks occurred off Galicia in October 2025, suggesting the orcas are neither bored nor scared away. Fifteen animals, none larger than about 21 feet, have rewritten the passage notes for one of the world’s most traveled stretches of water, and the next chapter is still being written at sea.
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