'I've Never Seen or Heard of Attacks': Scientists Baffled by Orcas Harassing Boats

By Susan Smillie, Guardian UK

13 September 20

Reports of orcas striking sailing boats in the Straits of Gibraltar have left sailors and scientists confused. Just what is causing such unusually aggressive behaviour?

hen nine killer whales surrounded the 46ft boat that Victoria Morris was crewing in Spain on the afternoon of 29 July, she was elated. The biology graduate taught sailing in New Zealand and is used to friendly orca encounters. But the atmosphere quickly changed when they started ramming the hull, spinning the boat 180 degrees, disabling the autohelm and engine. The 23-year-old watched broken bits of the rudder float off, leaving the four-person crew without steering, drifting into the Gibraltar Straits shipping lane between Cape Trafalgar and the small town of Barbate.

The pod rammed the boat for more than an hour, during which time the crew were too busy getting the sails in, readying the life raft and radioing a mayday – “Orca attack!” – to feel fear. The moment fear kicked in, Morris says, was when she went below deck to prepare a grab bag – the stuff you take when abandoning ship. “The noise was really scary. They were ramming the keel, there was this horrible echo, I thought they could capsize the boat. And this deafening noise as they communicated, whistling to each other. It was so loud that we had to shout.” It felt, she says, “totally orchestrated”.

The crew waited a tense hour and a half for rescue – perhaps understandably, the coastguard took time to comprehend (“You are saying you are under attack from orca?”). To say this is unusual is to massively understate it. By the time help arrived, the orcas were gone. The boat was towed to Barbate, where it was lifted to reveal the rudder missing its bottom third and outer layer, and teeth marks along the underside.

Rocío Espada works with the marine biology laboratory at the University of Seville and has observed this migratory population of orca in the Gibraltar Straits for years. She was astonished. “For killer whales to take out a piece of a fibreglass rudder is crazy,” she says. “I’ve seen these orcas grow from babies, I know their life stories, I’ve never seen or heard of attacks.”

Highly intelligent, social mammals, orcas are the largest of the dolphin family, and behave in a similar way. It is normal, she says, that orcas will follow close to the propeller. Even holding the rudder is not unheard of: “Sometimes they will bite the rudder, get dragged behind as a game.” But never with enough force to break it. This ramming, Espada says, indicates stress. The Straits is full of nets and long lines; perhaps a calf got caught.

But Morris’s was only one of several encounters between late July and August. Six days earlier, Alfonso Gomez-Jordana Martin, a 31-year-old from Alicante, was crewing a delivery boat near Barbate for the same company, Reliance Yacht Management. They were proceeding under engine when a pod of four orcas brought their 40ft Beneteau to a halt. He filmed them – it looks more like excitement and curiosity than aggression – but even this bumping damaged the rudder. And the force increased, he says, over 50 minutes. “Once we were stopped, they came in faster: 10-15 knots, from a distance of about 25m,” he remembers. “The impact tipped the boat sideways.”

The skipper’s report to the port authority said the force “nearly dislocated the helmsman’s shoulder and spun the whole yacht through 120 degrees”.

At 11.30pm the previous night, 22 July, Beverly Harris, a retired nurse from Derbyshire, and her partner, Kevin Large, were motor-sailing their 50ft boat, Kailani, just off Barbate at eight knots, when they came to a sudden standstill. It was flat calm, pitch black. They thought they’d hit a net. “I scrambled for a torch and was like, ‘Bloody hell, they’re orcas,’” says Harris. The couple checked their position and found the boat pointing the opposite way. They tried to correct several times, but the orcas kept spinning them back. “I had this weird sensation,” Harris says, “like they were trying to lift the boat.” It lasted about 20 minutes, but felt longer. “We thought, ‘We’ve sailed across the Atlantic, surely we’re not going to sink now!’” Their rudder was damaged but got them to La Línea. It was a long night. “Kevin said I should get some sleep. I said, ‘Are you joking? I’m having a gin and tonic,’” recalls Harris.

While enjoying her drink, Harris could have spared a thought for Nick Giles, having a sleepless night alone after an almost identical encounter off Barbate just two and a half hours earlier. He was motor-sailing, and playing music when he heard a sudden bang “like a sledgehammer”. The wheel was “turning with incredible force” as the vessel spun 180 degrees, dislodging the autohelm and steering cables. “The boat lifted up half a foot and I was pushed by a second whale from behind,” he says. While resetting the cables, the orca hit again, “nearly chopping off my fingers in the mechanism”. He was pushed around without steering for about 15 minutes before they left him.

Catastrophic encounters between whales and boats are not unknown – the best-known events all took place in the Pacific. In 1972 the Robertson family from Staffordshire were shipwrecked off the Galapagos Islands after an orca strike (their book, Survive the Savage Sea became a classic). The following year, also on the way to those islands, Maurice and Maralyn Bailey’s 31ft boat was holed by a sperm whale. In 1989 William and Simone Butler lost their boat as a huge pod of pilot whales rammed them. In these and all other known cases, the mammals ignored the humans who took to life rafts; it was the boats that attracted their ire. More usually in encounters, the whale is left dead or injured. The International Whaling Commission records these strikes – more collisions are occurring with private boats as technological advances increase performance speeds.

The encounters described around Barbate were certainly frightening for the crew, who understandably felt targeted, but it’s unlikely they were meant as aggressive attacks. At least two other boats had harmless encounters. On 20 July Martin Chambers, a yacht master for Allabroad Sailing Academy, was unconcerned when they were joined by a pod near Barbate. One individual “had hold of the rudder and stopped us moving the boat”, he says. “That’s the first time I’ve seen them do that.” It seems the encounters increased in intensity, but it’s also worth considering that different boat constructions can suffer different outcomes – rudders on some modern boats can be quite fragile.

“These are very strange events,” says Ezequiel Andréu Cazalla, a cetacean researcher who talked to Morris. “But I don’t think they’re attacks.” Orca specialists around the world are equally surprised, agreeing the behaviour is “highly unusual”, but are cautious, given that the accounts are not from trained researchers. Most agree that something is stressing the orcas. And when it comes to sources of stress, there are plenty to choose from.

The Gibraltar orcas are endangered – there are fewer than 50 individuals left, with a continuing decline projected – adults and juveniles are sustaining injuries, suffering food scarcity and pollution. Their calves rarely survive. The Gibraltar Straits is, Cazalla points out, “the worst place for orcas to live”. This narrow stretch of water is a major shipping route. And the presence of orcas attracts more marine traffic – highly profitable whale-watching. Theoretically, it is regulated, but some operators flout rules about speed and distance to chase the animals. Constant harassment by boats affects the orcas’ ability to hunt. Which brings us to the biggest stress of all: fishing.

The orcas return to this noisy, polluted stretch of water for one reason – to feed. They specialise in hunting bluefin tuna, also highly prized by humans. The near collapse of bluefin tuna between 2005 and 2010 “has led this orca population to the very edge, with about 30 adults left”, says Pauline Gauffier, who has studied them.

The Straits is an important migratory route for the tuna. It has been economically crucial to this region for thousands of years – the Romans produced coins in Cadiz depicting the once bountiful fish. Local fisheries still use an ancient technique – almadraba, a complex system of trap nets. Each spring, the bluefin arrive to spawn in the Med; many find their way into the nets instead. In July and August, as the tuna leave for the Atlantic, the fishermen switch to drop lines – baited with fish and lowered with rocks. These artisanal techniques are far less harmful than trawling, purse seining or driftnets – and than the reckless sport-fishing boats speeding at 10 knots, trailing long lines.

“They target the orca, because they think there must be tuna under the pods,” says Jörn Selling, a marine biologist for Firmm whale watching and research foundation with 17 years’ experience in the Straits. “They go right through the pods, their hooks cutting the dorsal fins”.

In the past, the orca chased the bluefin to exhaustion, but with fewer and smaller fish available, and the pressures from human activity, some have adapted. As a result, there now exists what biologists call “depradation” – a complex balance between the orca, tuna, and humans – and what the fishermen call “stealing”.

Since 1999, two of the Straits’ five pods have learned to take tuna from the drop lines, leaving the fishermen pulling up the tuna head alone. It’s infuriating for the fishermen, but for the orca, this is high risk. Several have sustained serious injuries. “We see marks caused by fishing lines,” says Selling. “We hear about young orca getting hooked.” There are two females with severed flippers – “Lucia”, Selling says “lost her baby together with her flipper, due to the interaction with tuna fishermen”. Gauffier points out that “there is little the fishermen can do to avoid line or hook injuries” when orca interact; and it’s not known what caused the injuries. But many conservationists suspect some fishermen retaliate violently.

“The fishermen hate the killer whales,” says Selling. The orca are protected, but “unobserved, the fishermen do what they want. They see them as competitors.” 

Stories persist of fishermen stunning orca with electric prods, throwing lit petrol cans, cutting dorsal fins. Cazalla has seen two orca with recent injuries (Morris thinks there was an injured individual at her boat). “One has a significant scar – you can see white tissue so it’s deep.” This, he thinks, is unlikely to be from a propeller, which would cause multiple scars. 

Selling points out that the orca interact with the almadraba as well as drop-line fishing, and talks of a male which worked out how to navigate the labyrinth of submarine nets to take tuna in Barbate years ago. This orca was later observed with serious injury to its dorsal fin. It hasn’t been seen since.

But the orca have endured harassment for decades. What explains the new behaviour? Was there reduced noise during the Covid lockdown? Selling says yes. “No big game fishing, no whale watching or sailing boats, no fast ferries, fewer merchant ships.” He’s intrigued by the idea that the orca had two months with reduced noise – “Something most of them probably never experienced before” – and considers the possibility they felt angry as the noise restarted (Gauffier thinks this unlikely, but notes that the Barbate pod still actively chases tuna, “for which they need a quieter environment”).

There is one very unscientific phrase I hear repeatedly from several researchers: “Pissed off”. Some speculate that the multitude of stresses these highly sentient cetaceans have endured – years of grieving lost calves, injuries, competition for fish, coupled with a pause and reintroduction of human activity, could have affected their behaviour. There is a great deal we don’t yet know about orca, which, like us, have evolved complex cultures and different languages around the world. A couple of years ago Ken Balcomb from the Center for Whale Research talked about endangered orca being dependent on scarce chinook salmon in the Pacific Northwest. “I’ve seen them look at boats hauling fish. I think they know that humans are somehow related to the scarcity of food. And I think they know that the scarcity of food is causing them physical distress, and also causing them to lose babies.”

Sounds like anthropomorphising? Lori Marino from the neuroscience and behavioural biology program at Emory University in Atlanta found in orca brains an astounding capacity for intelligence. “If we are talking about whether killer whales have the wherewithal and the cognitive capacity to intentionally strike out at someone, or to be angry, or to really know what they are doing, I would have to say the answer is yes.”

Meanwhile, Nick Irving from Reliance is wondering if he should send clients’ boats out after the last three sustained damage: “Is it reckless?” Neither of us say it, but we’re both thinking he doesn’t want to be the mayor in Jaws – the obvious, if lazy stereotype that comes to mind. Word is starting to get out, frustrating Espada. Friends call, asking about the “attacks”, if it’s safe to swim. “Are you mad?” she asks. “Of course it’s safe!” As shark conservationists know all too well, it’s difficult to protect endangered animals with a bad image.

This tiny population’s presence is of huge importance, and if human activity is affecting their behaviour, human activity must be regulated. Gauffier has presented the Spanish Environment Agency with a conservation plan proposing that in the Barbate area, “activities producing underwater noise should be reduced to a minimum”. This is the very least that should happen. Each sailor I spoke to was concerned that their activities had stressed the orca. Victoria Morris, who has been searching for a specialist subject when she returns to study marine biology in autumn has found her topic. The Gibraltar orca has one more ally – which is good because these majestic, beleaguered mammals need all the help they can get.