The orcas are learning.
Back in 2020, the international media took notice of a unique problem off the coast of Gibraltar -- killer whales were ramming and sinking yachts and sailboats with increasing regularity.
The issue is only getting worse, and now the orcas are showing signs of new tactics. Last week, they attacked again. They broke the rudder off a sailboat and pierced its hull, resulting in an emergency rescue by authorities, including a helicopter, and the vessel being towed to port. The incident marked a noticeable change in the behavior typically observed -- the orcas might be teaching the skill to their young.
Teams of scientists have descended upon the Strait of Gibraltar over the last few years to understand what's driving the ocean's apex predator to attack pleasure craft.
One of the leading theories early on was that black anti-fouling paint was somehow an attractant. According to John Burbeck and the Cruising Association, who are leading a taskforce to collect and analyze data from each incident, a high percentage of boats in the attacks had black anti-fouling paint on their hull.
According to Burbeck, “There are a high percentage of boats that are attacked that have got black antifouling. A low percentage of boats with black antifouling are having trouble-free voyages. If, on trouble-free voyages, you’ve only got 25% of boats with black antifouling, why on the attack side, have you got more than 50% with black?”
Data gathered by the Cruising Association in 2022 showed that 73% of yachts involved in an in incident were damaged, and that around 25% had to be towed to port. More than 50% of the boats had black anti-fouling paint.
Now the attacks are not only increasing in intensity and duration, they're also involving juveniles. While some initial attacks were reported to be a single whale ramming or 'playing' with a vessel's rudder, newer accounts have documented pods of whales, including juveniles in tow, engaging in what appear to be coordinated attacks.
On May 4th, orcas attacked a sailboat off the coast of Gibraltar, leaving it damaged and rudderless. According to reports, three orcas were involved. The crew had to abandon the ship, and the boat sank shortly thereafter.
A particular female orca known as White Gladis was thought to be ringleader of the incident, and scientists are now suggesting that the attacks may be a reaction to trauma from a previous collision with a boat, or that Gladis may have been previously trapped by fishing nets. It's well-known by fishermen in the Strait that orcas will follow commercial fishing vessels to snag bluefin tuna before fishermen can reel them in.
Furthernore, it's believed White Gladis was also a participant in a May 2nd attack that involved 6 whales trailing a 46-foot sailboat for over an hour near Tangier in Morocco. While the boat didn't sink, it did incur extensive damage. Footage from one of the sailors, April Boyes, shows the orcas working around the boat, as well as the rescue and the repair efforts in port.
(April Boyes/Instagram @april_georgina)
Alfredo Lopez Fernandez, a marine biologist at Portugal’s University of Aveiro, told Live Science that the incidents involving White Gladis are possibly a “critical moment of agony.”
According to Fernandez, “The orcas are doing this on purpose, of course, we don’t know the origin or the motivation, but defensive behaviour based on trauma, as the origin of all this, gains more strength for us every day.”
For Burbeck, the team leader at the Cruising Association: "There are interactions with orca where the skippers report describes adult orca apparently demonstrating the behaviour to juveniles. There are other interactions where adults act alone and where juveniles act alone. There is no standard orca behaviour, it varies from apparent curiosity to stroking the rudder to playing with the yacht by spinning it, to violent attacks on the rudder which breaks it off.”
There have already been 25 interactions reported in 2023. According to the Cruising Association, “one yacht sank, seven had extensive damage, seven had moderate damage, and one had minor damage. Nine had no damage and eight needed a tow,” said Burbeck.
So, is White Gladis passing along these skills to her offspring? Perhaps not directly, but since orcas are so smart it appears her young are mimicking her behaviours.
This theory gained more traction when the German sailing yacht Alboran Champagne was also attacked in early May. The boat was flooded due to a piereced hull caused by a torn rudder, and it was sent adrift to sink.
The boat’s captain, Werner Schaufelberger, told German magazine Yacht that he saw two smaller whales imitating the ramming tactics of the larger orca, believed to be White Gladis.
“The attacks were brutal. There were two smaller and one larger orca. The two little ones shook the rudder while the big one kept running and then rammed the ship from the side with full force. We were then (turned) 90 to 100 degrees different."
“The two little orcas copied the bigger one’s technique and, with a slight run-up, came darting towards the boat. Mainly on the rudder, but also the keel.”
For Dr. Lopez and his team, they believe that "the traumatised orca (White Gladis) is the one that started this behaviour of physical contact with boats."
“We do not interpret that the orcas are teaching the young," said Lopez, "although the behaviour has spread to the young vertically, simply by imitation, and later horizontally among them, because they consider it something important in their lives."
While the behavior continues to baffle scientists, authorities and those tracking the incidents have advised all vessels traveling through the Strait to stay in shallow water less than 20m deep. They also advise staying within two miles of shore, and to keep updated by following live information feeds from GT Orca Atlantica.
Comments