How Realistic Is the Shark Science in “The Shallows”?

We ask shark expert Chris Lowe whether the science in the upcoming shark thriller has any teeth. Beachgoers: You’re welcome.

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When The Shallows hits theaters June 24—non-coincidentally kicking off both Shark Week and beach vacation season—it will follow in a long line of shark thrillers. In the grand tradition of JawsOpen Water and The Reef, The Shallows tells one surfer’s story of survival as she evades a rogue great white shark with a taste for human flesh just 200 yards from shore.

Films about ravenous great white sharks have long captured the imaginations of moviegoers, and this one appears to be no exception. The anticipated summer blockbuster, starring American actress Blake Lively, has already garnered a 95 percent interest rating on Rotten Tomatoes. But just how much imaginative license did filmmakers take when it came to shark behavior?

We spoke with shark biologist Chris Lowe at the California State University, Long Beach to see what the trailer got right about great white sharks—and what was just Hollywood magic.

Let’s dive right in. Is there anything about the shark behavior in the trailer that catches your attention?

The film looks like it has a lot of real footage of sharks. Of course, it’s unbelievably rare to catch an actual shark attack on film, but I thought the way the trailer portrayed the attack on the female surfer was pretty realistic.

What’s your take on the shark breaching to eat a surfer?

We know that white sharks hangout in subtropical places where it’s not unusual to see someone surfing without a wetsuit, so that’s not totally implausible. However, places where they do jump out of the water in pursuit of prey are temperate—places like South Africa. We typically only see white sharks breaching in places where they’ve had to adapt their behavior to capturing fast, nimble prey like Cape fur seals. What kind of nimble prey exists in tropical waters?

My guess is probably not a human.

Right. Not a human, not a sea turtle, and there aren’t really any tropical seals left. So that’s the part that’s unrealistic. I look at that and chuckle a little.

What about the shark’s stalking behavior around the rock and then by the buoy? Is that typical?

Based on tracking data done in certain locations, we know sharks patrol certain areas waiting for seals to haul out on beaches. So I wouldn’t call it stalking; I would call it patrolling. While it’s certainly possible they stalk prey, we don’t have a lot of evidence showing how they play this “cat and mouse” game.

Films like Jaws, The Reef, and now The Shallows depict a rogue shark that will stop at nothing to devour its victim. Do "rogue sharks" exist?

That was a theory put forth back in the 1950’s, and we haven’t been able to shake it. For example, in Jaws, they say the shark has set up a territory and its going stay as long as there are people to eat. There’s just no good evidence that the same shark has been involved on multiple attacks on people over time.

Would a shark ever stalk just one prey animal?

Not very likely. A lot of these predators are smart enough to realize when they’re wasting their time. There are some predators that are willing to put in more effort to track down a single prey, like mountain lions (a lot of terrestrial predators are much better at that). But white sharks have to constantly be moving, which is biologically expensive. 

It seems like shark encounters are popping up in the news pretty frequently, which is rekindling some serious shark hysteria. Have there actually been more shark attacks or does the media just report on it more often?

It’s a little bit of both. There are more people in the water than ever before. That automatically increases the chances of an encounter. In many places, sharks have been overfished for over 50 years. We recognized this problem decades ago and in some places like the U.S., we have put in place regulations that better protect sharks and now they’re coming back.

If you look at the rate of human population growth—which we can use as an indicator of how many people are going in the water everyday—and consider how fast shark populations are growing, people are getting attacked more, but not as much as one might expect given the rate at which both populations are increasing. What that tells me as a scientist is that we are simply not on their menu.

Why would a shark bite a person in the first place?

Shark attacks are broken into two categories: provoked and unprovoked. Provoked attacks are simple. A fisherman catches a shark, the shark tries to get away, and the fisherman gets bitten. The person did something to induce that attack, usually requiring physical contact. 

The unprovoked attacks are a little harder to explain. All we know is what we base off of statistics or limited eye-witness accounts. Eighty-five percent of people never see the shark coming. In addition, with over 80 percent of people bitten, no flesh is removed.

One reason shark bite people might be because they either consider us as food or have mistaken us as food. That might explain why some people are bitten, but not consumed. The shark rushes up, tastes us, and leaves when it realizes we’re not their normal prey.

Another theory is that sharks are acting defensively. Just like any other animal on the planet, if it feels threatened it will defend itself. Sharks do something called agonistic display, where they contort their body to let other sharks or even people know it feels threatened. If a surfer is approaching a shark and the shark starts to feel threatened that something is invading its space, then it lashes out. It races in, takes a bite, and then takes off.

So we just don’t know. We don’t know what the circumstances were right before someone got bit because nobody sees what the shark is doing before the event. This is what makes it really difficult to say why sharks bite people.

Many people are fascinated by sharks, but that doesn’t mean they want to get in the water with them. Why did you decide to study sharks?

When I was younger, I swore I would never work on white sharks, because I thought they were overrated. As a shark biologist, I studied hammerheads, tiger sharks, sandbar sharks, Galapagos sharks, leopard sharks—all of which were underrepresented (in the research). But after I came to California, we started researching baby white sharks working with Monterey Bay Aquarium, and that got me intrigued.

They’re kind of like the ultimate athletes of the shark world. They’re warm-bodied, and as long as they keep swimming they can keep their bodies warmer than the water. That’s how a 4,000-5,000 pound shark can launch itself 6-8 feet out of the water. In addition, they can dive 1,000 meters (3,000 feet). The water temperature down there is just above freezing. Physiologically, they’re the Formula One race cars of the shark world.

It sounds like we know a lot about great white sharks.

But there’s a lot that’s still unknown. Doing this work is really expensive. One satellite transmitter costs $5,000, and we don’t usually get them back after they’ve been deployed. Nonetheless, this technology has greatly changed our understanding of white sharks.

Thirty years ago, if you asked a shark biologist what kind of shark a white shark was, they’d probably say a coastal shark. That is because we only really saw them along the coastline during the fall months off California when they were hunting elephant seals. However, using satellite transmitters my colleagues have found that those sharks really only spend 1-3 months in close to shore before migrating out into the middle of the Pacific, where they will spend 8-18 months before venturing back to shore.  Now, I wouldn’t call a white shark a coastal shark, I’d call them an oceanic shark. 

The good news is we now have all this cool new technology—drones, underwater robots, new sensors and low-light cameras at our disposal. Unfortunately, every time we want to do a study to answer a simple question you’re looking at a half million dollars in funding to do the work. Very little government funding supports white shark research.

Despite the fact that it’s such a charismatic, well-known animal?

Right. And this is where the Discovery Channel and movies like Jaws have done sharks a disservice. They have given the public the false impression that we’ve already answered most of the important scientific questions around sharks. I’ll give you an example. When do sharks feed?

Dawn and dusk, right?

So that’s the theory, but there’s no evidence to support it. The urban myth is that sharks feed at dawn and dusk, so that’s the most dangerous time to be in the water.  Part of this comes from the fact that you have a lot of surfers out at dawn and dusk and surfers are the ones quite often bitten. However, the reality is that there is no pattern. Our lab wanted to research this further by feeding sensors to the shark that measures their stomach pH, which would allow us to actually tell when the shark has eaten. One of the reasons why we couldn’t get funding was because some people thought we already knew all that—and some of those people were scientists.

Great white sharks are listed as “vulnerable” by the IUCN Red List of Threatened Species. How are they doing in the wild today?

Humans have certainly affected white shark populations, either by killing them in fisheries or having an impact on their food sources. Over the last 10 years we have been studying juvenile white sharks, we have seen evidence of population increase. We’re seeing populations increasing pretty much everywhere, i.e. in waters off New England, Australia, and New Zealand.

We have three to five times more people in the U.S. and along coastal habitats now than in the 1970s, and yet we’re seeing recovery from all these predator populations. I see that as a sign we’re doing something right. White sharks have been protected for 10-20 years now. I’m hoping that people can look at major problems today like climate change and say, “well, we saw declining predator populations as a major problem in the 60s and 70s. A lot of people thought we’d never fix those problems and we have. If we can fix that, why can’t we fix climate change?”

Okay, say I’m planning a trip to the beach this summer. What are my chances of being bit by a shark?

Extremely unlikely. Like winning the Powerball lottery unlikely.

  Learn more about the seas with the Smithsonian Ocean Portal.

About L.K. Ward

L.K. Ward is an Earth Science Video Producer at NASA Goddard and former science writer for the Ocean Portal. She is a graduate of Scripps Institution of Oceanography in San Diego, California.

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