Do Sharks Attack Boats? (Data, Reasons Why & Safety Tips)

Anyone who’s seen the 1975 Steven Spielberg classic Jaws knows that the heart of that thriller is not the gruesome shark attacks off Amity Island’s swimming beaches, but the offshore pursuit of the offending fish aboard Captain Quint’s boat the Orca.

That hunt, which occupies essentially the whole second act of the film, culminates (spoiler alert!) with the huge, harried great white shark turning the tables on the Orca and sinking it.

As much as Jaws—a legitimately fine movie, but also one partly responsible for the unfair global demonization of sharks—inspired nightmares for a generation or two of swimmers, it also likely unnerved more than few boaters.

Jaws infamously overhyped the danger that sharks pose, to swimmers and boaters alike. Still, it’s worth exploring the question:

Do shark attack boats? What kinds of sharks might attack boats and are you safe in a kayak or a life raft?

Photo by Patrick Crowley/Flickr

Sharks do occasionally —very occasionally—attack boats, a legitimately freaky experience for the occupants. While such hair-raising incidents rarely end in harm to people, they do sometimes result in a boat coming out rather worse for wear. There have been a few notable cases of shark attacking and sinking boats. Generally, shark attacks on boats are cases of mistaken identity or light territorial posturing.

In this article, we’ll dig a bit into this subject, considering which shark species are most commonly involved in boat attacks and examining some notable examples.

We’ll also cover some of the basics of shark safety for boaters who find themselves sharing the high seas with these primordial marine beasts.

Sharks & Boats: Provoked vs Unprovoked Attacks, Nudges, Bumps & More

In this article, when referring to shark attacks on boats, we’re using “attack” in a very broad sense.

Many of these encounters involve a shark nudging or bumping a boat, or biting part of it (such as the hull or the motor).

Only rarely are we talking a shark truly assaulting a watercraft—that is, slamming and biting it repeatedly with great power and speed.

Sometimes that happens, to be sure, but for many of these events the label “shark attack” is perhaps a little overly dramatic.

It’s worth noting that the International Shark Attack File (ISAF) includes a category “boat bites” in its annual tallying of shark attacks on people.

“Bites on vessels of any size (from kayaks to yachts) are included and subcategorized as provoked or unprovoked,” the ISAF notes.

A provoked attack is really the most likely: a fishing boat or research vessel being bitten by a hooked shark. (And bites by hauled-in sharks actually onboard fishing boats aren’t uncommon, for which you can’t exactly blame the shark.)

But for the rest of the article we’ll be focusing on the much more unlikely unprovoked situations.

Types of Sharks Involved in Attacks on Boats

The shark species most often implicated in unprovoked attacks on boats is the great white shark.

This is the biggest of all predatory sharks, capable of reaching lengths of 20 feet or more and weights beyond two tons.

The white shark’s smaller relative the mako has also occasionally been known to chomp boats.

Among other kinds of sharks implicated in occasional boat bites include such carcharhinids (requiem sharks) as:

  • tiger sharks
  • bull sharks
  • blue sharks
  • and bronze whalers
  • plus hammerheads.

Even a predominantly deepwater species—the sixgill shark, which may grow past 16 feet long—has been involved in at least one incident:

Some big sixgills scavenging a whale carcass on the seafloor aggressively bumped the Blue Planet II documentary film crew’s submarine, for example!

Shark Attacks on Boats: Real Examples & Case Studies

The most numerous, and generally the most serious, shark attacks on boats have been the work of great whites.

Several of the relatively few shark attacks recorded in Canada, for example, were white-shark strikes on boats.

In 1932, a white shark estimated at 15 feet struck a motorboat in the Bay of Fundy multiple times, denting its propeller blades and scarring the hull and keel.

In 1953, a roughly 12-foot white shark that had apparently trailed a particular white-hulled dory off Cape Breton for the better part of a week ultimately attacked and sank it.

Though the shark didn’t attack the two men aboard who ended up in the water, one of them drowned while trying to swim to shore.

Great white sharks have also attacked multiple boats on North America’s Pacific coast. In 1952, for instance, a great white sank a skiff near Bodega Bay.

White-shark attacks on boats beyond North American waters are also known to occur.

In June 1992, a good-sized white shark made multiple bites on the hull of a 19-foot wooden fishing boat off the Japanese island of Shikoku—mere months after a fatal great-white attack on a diver in the same general area.

In April 2022, a great white shark circled a boat off Mandurah in Western Australia for more than an hour, biting its motor multiple times.

As we mentioned, requiem sharks have also sometimes set their sights on watercraft.

In March of 2018, a bull shark off the Florida coast chomped on a 30-foot fishing boat multiple times, an event captured in drone footage.

And in May 2022, fishermen in Coral Bay, Western Australia filmed a roughly 10-foot-long bronze whaler (aka a copper shark) ravaging their propeller for several minutes.

Sharks & Paddlecraft (Kayaks, Life Rafts, Etc.)

Photo by cweyant/Flickr

All else being equal, kayakers are the boaters probably most vulnerable to injury when it comes from a shark assault, only because they’re piloting small, narrow crafts offering minimal protection.

A shark bumping a yacht or sportfishing boat is unlikely to demolish the vessel or knock occupants into the water (though it wouldn’t be out of the realm of possibility).

A large shark ramming a kayak (or, in rare cases, a life raft), conversely, could easily capsize it and/or toss the paddler into the drink.

As Victoria Scott of the Canadian Shark Conservation Society noted to Paddling Magazine, however, most so-called “attacks” on kayaks are better described as “shark encounters,” given an actual shark attack on such a boat would typically be much more devastating than what usually plays out.

“Sharks are incredibly effective hunters,” she said. “If one was to attack a sea kayaker there is no doubt the shark would win every time.”

As recreational and sea kayaking have continued to grow in popularity, shark bites and bumps on ‘yaks have occurred around the world, while remaining rare in the big scheme of things.

In June 2008, a woman was thrown from her kayak when a great white shark struck it off Catalina Island in Southern California; she was not attacked herself.

That same island saw a bite to a kayak in 2019 executed by what was reckoned to be a 19-foot-long white shark.

In 2018, a tiger shark estimated at 13 feet long overturned a kayak off Queensland, Australia’s Sunshine Coast. The shark apparently tried to bite the kayaker in the water, though this was unsuccessful.

The paddler was able to climb aboard another kayak that had come to his aid; the tiger shark continued circling until rescuers on jet skis arrived.

Like shark attacks in general, strikes by sharks against kayaks don’t usually result in serious injury to the paddler. But there have been exceptions.

A great white shark was likely responsible for the deaths of two paddlers, Tamara McAllister and Ray Stoddard, off the Southern California coast near Malibu in January 1989.

The two had gone for a morning paddle out of Latigo Point, aiming for Paradise Cove as a turnaround point. Their lashed-together kayaks were found off Point Mugu the following day, one with a hole in the bottom.

The body of McAllister was discovered the day after that, with a 13-inch bite wound attributed to a roughly 16-foot-long great white. Stoddard’s body was never found, though he was presumed to have also been killed by the shark.

Why Might Sharks Attack Boats?

Experts reckon shark attacks on boats stem from a number of different motivations. In many cases, a shark may be simply investigating a watercraft as potential prey.

That’s sort of intimidating-sounding, but a shark investigating a possible food object can only really do so by nudging or biting it—explorations that often aren’t particularly aggressive in nature.

A great white shark, which as an adult favors such large prey as seals, sea lions, dolphins, and small whales, often ambush marine mammals from below, keying into their silhouettes; a boat’s outline at the surface may appear similar enough.

Thus, a shark might see a motorboat or kayak as a potential lunch, and chomp it once or twice as a test. That’s usually all it will amount to, given a fiberglass or wooden hull is much less appetizing than a blubbery pinniped.

(A kayak might conceivably trigger the predatory attention of a tiger shark, too, given that species’ fondness for sea turtles and seals.)

Sharks can sense electrical impulses in the water, which helps them zero in on the muscle contractions of prey. The electrical field produced by a boat motor or propeller, though, might fool a hunting shark. This may explain a goodly proportion of sharkbites on boats.

Some attacks on vessels by white sharks, as with attacks on people, have occurred in the presence of marine mammals.

For example, in the 1950s a fiberglass boat being used to survey pinnipeds off Mexico’s Guadalupe Island was violently pummeled by a great white. And onshore eyewitnesses in the vicinity of the fatal attack on the two kayakers near Malibu in 1989 saw commotion in the water that morning in the area and “very agitated” sea lions scrabbling up onto a buoy amid the splashing.

It’s been theorized that the white shark that killed those kayakers may have targeted their boats as prey—a case of mistaken identity that might have been further encouraged by sea lions in the immediate vicinity.

It seems clear in some cases that sharks actively feeding may sometimes bump or bite boats out of territoriality, perhaps perceiving them as competitors for the food source. Some wide-ranging examples illustrate this scenario.

In 1989, a large white shark (estimated at anywhere from 16 to 20-plus feet long) feeding on a harbor seal in Monterey Bay circled and then repeatedly rammed a 35-foot boat that drifted near. It also rolled on its side in the water and slapped the boat’s swimstep and propellor with its tailfin.

Once the boat had moved more than about 65 feet from the seal carcass, the shark left it alone.

That same year, a 10- to 13-foot white shark scavenging a whale carcass off Palos Verde bit and nosed a 38-foot fiberglass boat that came into the vicinity numerous times.

(Both of these cases are described in this document, scanned by the Shark Research Committee.)

In 2016, meanwhile, a man named Keith Poe who was attempting to tag great white sharks scavenging a dead humpback off the coast of Los Angeles County reported his 24-foot boat attacked multiple times over several days by the sharks, some of which were as long as 18 feet.

One of these strikes was quite intense. “I thought a sailboat slammed into me because I didn’t hear a motor,” Poe was quoted in a Men’s Journal article. “I was sure the fiberglass was broken through, then I saw the teeth marks and was blown away. It scared the hell out of me.”

A Honolulu Ocean Safety Division official monitoring tiger sharks feasting on a dead humpback off the Oahu coast in April 2021 on a jet ski reported one roughly 12-foot shark aggressively moving at the watercraft, “almost lunging,” in an apparent attempt to drive it away.

The sixgill sharks shoving a submarine in the vicinity of a dead whale they were scavenging mentioned earlier in the article is likely another example of sharks guarding a food source.

Sharks may also end up biting watercraft because they’re accustomed to pilfering bait or hooked fish from fishing boats. As the ISAF notes, “Some sharks can be habituated to expect food just by hearing the sound of an engine.”

Wrapping Up & Final Safety Tips

A shark attack is pretty low on the list of things to worry about as a boater, given all of the much-more-likely dangers the activity presents.

But whenever you’re sharing space with a large, powerful predator, it’s good to be aware of common-sense safety protocol.

If you’re fishing and a big shark appears, take in your bait to avoid provoking a bite to your craft. Don’t approach a whale carcass out to sea, given a high likelihood of scavenging (and maybe riled-up) sharks.

Small crafts (especially kayaks) in particular should steer clear of pinnipeds, dolphins, and sea turtles, which might be being targeted by large sharks.

For more shark safety, check out:

Hope this helps!