Killer whales ‘playing’ with boats because they are bored

Killer whales are playing with yachts because they are bored now that food is so plentiful, experts believe.

Since May 2020, there have been 673 reports of whales approaching boats, often nudging or biting their rudders and in extreme cases sinking vessels.

Most of the interactions have happened around the Iberian peninsula, off the coasts of Gibraltar and Spain, and are believed to be the work of one group of orcas.

To get to the bottom of the strange, new phenomenon, the International Whaling Commission (IWC) convened a meeting of experts in Madrid who suggested that a rise in the bluefin tuna population could be to blame.

A report published this week found that the whales were unlikely to be “attacking” boats or sailors, but are instead engaging in new playful behaviour because they have time to kill.

“There is no evidence that the interactions between Iberian killer whales and vessels are aggressive,” the authors concluded.

“Those familiar with the region noted that in the recent past when bluefin tuna were at low numbers, the whales were preoccupied with finding and capturing sufficient prey.

“Now with bluefin recovery, perhaps these whales, especially the juveniles, have more leisure to explore novel behaviours.”

Reports show that interactions between whales and yachts most often occur during the day, between June and September, and last about 25 minutes.

Boats smaller than 40ft are the most likely targets and orcas most frequently target the rudder.

Earlier this month, killer whales sank a couple’s yacht in the Strait of Gibraltar, about 14 miles off Morocco’s Cap Spartel.

Water started flooding the boat after the orcas broke the rudder and punched a hole in the hull, and the pair were rescued by a nearby oil tanker.

Seven boats have now been sunk from whale attacks in recent years. It is usually young whales seen interacting with the boats.

Killer whales are known to play with objects and animals in the wild such as porpoises until they cause unintentional damage.

Orcas are also notorious for exhibiting distinctive behaviour for a few months before ditching the new habit as quickly as they picked it up.

In the late 1980s, killer whales in the Puget Sound area of the north-east Pacific began carrying dead salmon on their heads, a trend that quickly spread to two other pods. The whales carried fish on their heads over a six-week period.

Some killer whales have been spotted latching on to the dorsal fins of larger males to hitch a ride, while in 2005, an orca in Marineland learned how to to catch seagulls using regurgitated fish as bait – a trend that it passed on to fellow pod mates.

Recently, orcas in British Columbia have attacked crab pots, lifting and moving their anchors for no reason, while killer whales in the Salish Sea near Vancouver will harass porpoises.

Some experts believe that the young orcas may have developed a fondness for the bubbly disturbed water churned up by boat propellers, which is driving the playful behaviour.

Several have been spotted enjoying the high-pressure wake from propellers and researchers think that they may be ramming the rudder of sailing vessels to encourage the crew to turn on their engines.

The IWC report authors argue that it is wrong to see the interactions as “attacks” and say it is likely to be a playful fad which dies out over time.

“The behaviour has more in common with fads seen elsewhere and seems associated with play or socialising, perhaps encouraged by the recent increased abundance and availability of prey, reducing the time needed for foraging,” the report said.

“The use of the words such as aggression or attack to describe such interactions is thus inappropriate.

“It may be that the current fixation of Iberian killer whales with boats, and particularly their rudders, is such an ephemeral fad, that if it suddenly ceases, it might reappear again at a later date.”

However, the report said that although the orca behaviour was unlikely to be aggressive, it was still frightening for sailors and often caused damage to boats.

Currently, sailors are advised to switch off their engines and “play dead” until the whales leave the area, or make loud noises to scare the animals away.

But the IWC “strongly recommended” that mariners should not use acoustic deterrents, because it could harm the animals and other marine life, and may eventually draw orcas to boats.

They advise instead that sailors should move one to two miles away from the pod.

“Mariners need to be prepared for an interaction in these waters, knowing that they may need to be rescued,” said the report.

The Portuguese navy is currently testing long reverberant metal pipes that produce a ringing sound when struck to keep whales away from vessels.