Scientists Finally Explain Real Reason Behind Orca Attacks on Boats

By: Beth Moreton | Last updated: Jun 26, 2024

Since 2020, there has been an increasing number of reports regarding orca attacks on boats in the sea. Unhappy with what was happening, the Spanish and Portuguese governments ordered a report on the behavior to try and get to the bottom of what was happening. 

While people may have expected this supposed change in behavior to be the result of something specific, the scientists concluded that no behavior change has actually happened and that it was actually the result of new fads, playing and socializing.

The Iberian Peninsula Has Experienced Orca Attacks

The area that has been experiencing the main brunt of these orca attacks is around the Iberian Peninsula. Since 2020, there have been 673 orca attacks off the coast of Morocco, Spain and Portugal.

An orca jumping out of the water. Green trees are in the background.

Source: Thomas Lipke/Unsplash

These attacks are aimed at boats that are mostly medium-length sailboats smaller than 40 feet in length. They tend to focus more on the boat’s spade rudders. 


Orca Attacks Limited to the Iberian Peninsula

The attacks on the boats have been seemingly limited to the Iberian Peninsula. The behavior is rare, with one scientist stating that the attacking and sinking of boats caused by orcas has only happened there.

An orca swimming underwater.

Source: Lewek Gnos/Unsplash

20% of the carried out attacks have damaged the boats, with just 3 resulting in the boats sinking. The last boat to sink due to an orca attack was in May 2024. 

Many Orcas Live in the Iberian Peninsula

Scientists believe that part of the reason why these orca attacks are mostly happening in the Iberian Peninsula is because at least 50 known orcas are living there.

The fin of an orca above the water.

Iswanto Arif/Unsplash

Despite this, the orcas may be traveling further afield to carry out these attacks as an orca attacked a yacht just off the Shetland Islands, which is 1500 miles away from the Iberian Peninsula.

Boats Have Sunk Due to Orca Attacks

Some of the attacks haven’t been enough to cause damage. However, other attacks have been so bad that boats have actually sunk to the bottom of the ocean.

Three orcas swimming in the sea next to one another.

Source: Nitesh Jain/Unsplash

As a result of these attacks and to try to maintain the safety of the orcas, the Spanish and Portuguese governments ordered a report on why these orca attacks were happening to better understand their next moves. 

Orcas Sank a Sailing Yacht

The boats that orcas have been sinking aren’t just small boats. A group of orcas managed to sink a 50-foot sailing yacht in Gibraltar.

Two orcas in the ocean with sunlight bursting through the clouds and shining on them.

Gabriel Tovar/Unsplash

They were able to do this by ripping open the yacht’s hull, which is its watertight body. This was the latest in a long line of orca attacks on boats in the area.


The Crew Had To Be Rescued

When the crew realized what was happening, they had to radio for help and luckily they were rescued by a passing oil tanker.

An orca's tail coming out of the water with hills in the distance.

Ryan Stone/Unsplash

The hull of the yacht received the most damage during the attack, which caused water to come into it. This is what caused it to sink.


An Extra Thing to Account For

Due to the rise in orca attacks on boats, this is another thing that sailers and people working on boats have to consider before they go out to sea.

Two orcas swimming in the sea.

Gabriel Tovar/Unsplash

Before this, the only things that needed to be considered were wind, tide, and shipping conditions.


Orcas Interrupting Races

Back in the summer of 2022, a crew on a boat was sailing towards Tangier on the Moroccan coast as part of the Globe40 race, which is a global regatta.

Three orcas in the water, with trees and hills in the distance.

Miles Loewen/Unsplash

However, the race quickly came to a sudden end for the crew as orcas started attacking their boat, which left them feeling terrified.


Scientists Call Them Interactions

Instead of referring to them as attacks, scientists prefer for them to be known as interactions. This is because it’s not believed that the orcas are doing this in a hostile manner.

Two orcas in the water. One has its fin slightly poking out but the rest is underwater. The other has its fin and part of its body out.

Tamara Bitter/Unsplash

But regardless of whether it is an attack or an interaction, those on board the boats and yachts that are sourced out by orcas are terrified.


Attacks Are Putting Orcas at Risk

One of the worries with referring to what the orcas are doing as attacks is that it will eventually result in humans retaliating and attacking the orcas.

Three orcas swimming next to each other at sunset.

Gabriel Tovar/Unsplash

Scientists want to avoid this because it’s unlikely that they are actually ramming themselves against the boats as an act of aggression; it is probably due to something else.


No One Has Been Injured

Thankfully, there have been no reports of injury. Even in cases where people have been onboard a boat or yacht when it has begun to sink, no one has been injured.

The back end of an orca sticking out of the water.

Lachlan Gowen/Unsplash

However, at the rate at which all of this is happening, it will only be a matter of time before someone gets injured.


Orcas Killing Great White Sharks

It’s not just boats that orcas are attacking. A great white shark was found washed up on a beach with part of its body missing. Experts say that this was caused by another animal.

Three orcas' fins sticking out of the water with rocks in the background.


After researching, the researchers realized that this attack was caused by an orca. Orcas have been biting into the shoulders of great white sharks and tearing out their liver.


Theories on the Orca Attacks

Before the report was carried out, sailors, scientists and various others had theories about why these attacks continued.

Four orcas swimming next to each other in the sea.

Source: Mike Doherty/Unsplash

These theories included there not being enough food for all of the orcas in the sea, so they were fighting each other to get to the boats as they saw them as prey. Another theory was that these attacks were happening due to the rise in nautical activities after the COVID-19 pandemic put a stop to them. 


Orcas Are Intelligent Animals

Orcas are known to be intelligent animals, which is why another theory on this rise in boat attacks is that they found the boats intriguing objects and were trying to find out more about them. 

Three orcas swimming in the sea next to each other.

Source: Bart/Unsplash

Combine this with their love of playing, and it was believed that the orcas were just innocently playing with the boats, and any damage caused to them was an accident. 


Changing Conditions Causes Stress

Due to climate change, conditions on both land and sea have changed. This includes a rise in sea temperatures and a change in the amount of prey available.

Two orcas swimming next to each other in the sea. There is a mountain range in the background, and the sun is setting behind them.

Source: Bart/Unsplash

This can cause changes in the orcas’ behavior, which includes aggression and exhibiting territorial behavior. As a result, it can manifest as the orcas seemingly attacking the boats.


Bad Experiences Involving Boats

Just like humans, orcas are subject to having bad experiences. At one point, scientists believed that the attacks could be down to one or some of the orcas having a previous bad experience with boats.

Three orcas sticking their heads out of the water between two ice sheets.

Source: Bryan Goff/Unsplash

However, the report quickly discovered that a bad experience with a boat was unlikely to have caused these attacks. 


Orcas Are Being Playful

When studying the orcas during these attacks, scientists noted that they were exhibiting playful and social behaviors that didn’t suggest any malicious intent.

An orca jumping out of the water.

Rémi Boudousquié/Unsplash

According to the scientists, this is yet another reason to not refer to them as attacks, and to reframe this as being an interaction.


Orcas Have Long Been Known To Attack Things

Even though the rise in orca attacks has only happened in the last few years, killer whales have been known to carry out attacks for decades.

An orca's fin sticking out of the water.

Stephane Wegner/Unsplash

In a 1973 US Navy manual, it stated that orcas are “extremely ferocious” and will attack anything, including humans, at any given opportunity.


Orcas Don’t Kill Humans in the Wild

One thing that is important to note is that orcas are highly unlikely to kill a human in the wild. In fact, there have been no known reports of an orca killing a human in the wild throughout history.

Two orcas' fins sticking out of the water.

Francesco Ungaro/Unsplash

This is unlike polar bears and great white sharks, which have been known to do this. However, orcas have been known to kill their trainers when in captivity.


The International Whaling Commission Led the Report

The International Whaling Commission (IWC) was given the job by the Spanish and Portuguese governments to lead the report into the orca attacks. Marine biologist Alex Zerbini is the IWC’s chair.

A small group of orcas swimming in the sea.

Source: NOAA/Unsplash

What the report found was rather surprising, both to the governments and the scientists. They found it was likely due to a new fad or cultural tradition that the younger orcas had picked up from the older ones.


Orcas Like Playing With Boat Rudders

Boat rudders are one of the main things that orcas like to play with when in the sea. This means that when they’re bored or fancy a bit of playtime, they will go straight for the boat rudders.

An orca swimming in the sea.

Source: Tim Cole/Unsplash

Due to an increase in the amount of bluefin tuna in the sea due to conservation efforts, orcas don’t have to hunt as much for their food. Because of this, they have more playtime, which means more time to play with the boats.


One Orca Started a Trend

Humans aren’t the only beings on Earth who are subject to following trends, as orcas also do the same. It is believed that one orca started playing with a boat, which was witnessed by other orcas, who subsequently followed their lead.

An orca’s tail coming out of the water.

Source: Richard Sagredo/Unsplash

This isn’t the first time something like this has happened. There have been other instances of orca trends happening, such as wearing dead salmon as hats and playing games of chicken. 


What Mariners Can Do

The scientists who carried out the research have offered some advice to mariners about what to do if they see an orca approaching their boat.

Three orcas in the sea. One is sticking its head out of the water. A cruise ship is in the distance.

Source: Dick Martin/Unsplash

The advice is to move 2km to 3km away from the orcas as quickly as possible, preferably toward the coast or to an area where rescue can happen. While moving away might not prevent the attack from happening, it gives a better chance of lessening the amount of damage to the boat.