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Imagine you are an Air Force pilot and you just had the unpleasant experience of ejecting from your aircraft over the open ocean. You landed safely in the water and now you await rescue in an inflatable raft. But there is a problem: a few yards away you see a shark fin sticking out of the water. 

Your heart beats faster. What do you do now? The Air Force sought to answer that question in a 1964 training video that recently made the rounds on the unofficial Air Force subreddit. The 58-year-old video may seem dated to viewers today, especially due to its dire introduction.

“This shark and his relatives are long-established enemies of man,” says the narrator in the video, titled Shark Defense, which can also be found on the National Archives website. “He is a wicked, unpredictable opponent.”

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The next ten minutes of the video cover a long list of techniques downed aviators can use to avoid or scare away sharks, but some of the advice sounds a little hokey. For example, the narrator recommends yelling into the water, blowing a whistle underwater, rubbing your fingers across the surface of the life preserver or raft, blowing bubbles at the shark from your life preserver, or “tearing up paper into small pieces and scattering them all around the raft.”

“Sharks shy away from strange sights,” the narrator explains, as an orchestra plays in the background and an actor scatters paper around his raft.

At first glance, Shark Defense seems to be another silly old military training video, like the World War II-era How to Behave in Britain, or a 1953 video of an Army Ranger student joking about eating a porcupine. But before you toss rotten produce at the screen, keep in mind that back in the early 1960s, people knew much less about sharks than we do today. In fact, modern shark research began during the early years of the Cold War in part because so many U.S. service members were so afraid of sharks. 

In World War II there were several horrific, well-publicized shark incidents like what happened after the USS Indianapolis sank in the Pacific in 1945. Hundreds of sailors, many wounded from the blast that destroyed their cruiser, floated for days waiting for rescue, where they were eventually encircled by sharks and some were killed by them, though the exact number is unknown. The image of sharks attacking helpless sailors stranded in the open ocean was a powerful one that stuck with many service members.

“The military had a big morale problem,” Dr. Chris Lowe, a professor in marine biology and director of the Shark Lab at California State University Long Beach, told Task & Purpose. “Sailors were afraid to go to sea because of their fear of sharks. Aviators were afraid to ditch their planes in the water because of their fear of sharks.”

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The Pentagon wanted to help put troops’ minds at ease by giving them a way to survive shark encounters. At one point during World War II, the Navy even put future celebrity chef Julia Child on the project of developing some kind of shark repellant. That effort continued into 1958, when the Office of Naval Research helped stand up the first-ever Shark Research Panel, which had not a single shark scientist because they didn’t yet exist.

“The military basically reached out to a bunch of fish biologists and said ‘hey, who knows anything about sharks?’” Lowe explained. “Nobody really knew anything about them, so the military said ‘how about we fund you to develop shark repellant?’”

To develop a shark repellant, scientists first had to understand what stimuli attracted and repelled the animals. Thus, early shark research focused on sensory biology, Lowe said. The Shark Research Panel also began tracking shark attacks with details “such as location, environmental conditions, kind of shark, nature, and treatment of wounds, and type of activity the victim was engaged in at the time of the attack,” according to the Smithsonian.

Though the effort to develop an effective shark repellant was largely unsuccessful, it was the start of modern shark science. The 1964 video “Shark Defense” is a great example of its early findings, some of which ring true today — and some, well, not so much. 

How sharks find you

Early in the video, the narrator discusses the various ways sharks can be attracted to an aviator floating in the ocean. Garbage, urine, vomit, and feces are all ways to get a shark’s attention, the narrator says, but blood is the most potent signal.

“Blood in the water, any blood, human or otherwise, is extremely dangerous,” he says. “Two molecules of blood reaching a shark’s nostrils are enough to start him homing on you.”

Though it sounds extreme, there is some truth to the narrator’s statements, Lowe said. Many of the substances and behaviors the narrator mentions in the video can attract sharks, though at what range and whether it will provoke them to attack may not be as certain as the narrator makes it out to be.

A downed pilot scatters scraps of paper around him in one of the video's more dubious moments. (Screenshot via U.S. Air Force)
A downed pilot scatters scraps of paper around him in one of the video’s more dubious moments. (Screenshot via U.S. Air Force)

Sharks are sensitive to the amino acids found in organic material like blood, Lowe explained,  though it would be an exaggeration to say that two molecules could set them off from a mile away (a myth that still persists today). Keeping blood and waste out of the water is often a good idea, but shark responses to those stimuli can vary. It is a bit like kids at a picnic when a plate of brownies appears, Lowe said. Sometimes it might stir up a frenzy, especially when there may not be enough brownies for all the kids. But if there is just one completely full kid, they may not be interested. The same goes for the other stimuli described in the video: making bubbles may frighten some sharks, but it may make others more curious and actually drive them closer. 

“There’s a modicum of truth, but our notions of how sharks perceive their environment has changed,” Lowe said.

Another marine biologist had an example of how different stimuli can attract or deter different sharks.

“I’ve watched bubbles from my scuba regulator scare off a tiger shark when the bubbles made contact with its snout,” said Dr. Carl Meyer, with the Hawai’i Institute of Marine Biology. “But I doubt you would be able to squirt bubbles from a life vest in a way that would deter a shark.”

The narrator’s warnings about clashing colors attracting sharks are a good example of changing notions as scientists understand the animals better.

“We used to think sharks didn’t have good eyesight, then we did, then we thought they could see color, but then it turns out they can’t,” Lowe said. “Turns out they can really only see in one color.”

Sharks do have a high capacity to detect contrast, and high contrast can attract sharks, but they likely can’t form images with the same sharpness that humans or birds can, the biologist explained. They are also very sensitive to motion, such as a school of fish reflecting light. But just because a fish or a human presents sharp contrast or sudden movement, it may not necessarily mean that a shark will immediately start hunting. 

“It could even have an opposite effect,” Lowe said. “If sharks have been jabbed, poked, or stabbed by people in the water, and a shark recognizes a person, they could just as equally avoid people. Unfortunately, we have very little data because we can’t just throw people in the water for a shark attraction experiment.”

Still, one brand new study could shed light on just how often sharks swim right past humans. Lowe said white sharks often gather at southern California beaches because they serve as nursery habitats. By using drones, the two-year study found that sharks get as close to 50 feet off the beach, often without beachgoers noticing.

“We have hundreds of hours of video footage of surfers with white sharks swimming right underneath them, and the surfers don’t even know they’re there,” he said. “We have data to show that sharks and people are interacting daily and nothing has happened. 

“That film was made in 1964, and here we are in 2022 just finally getting the answers to these questions,” he added. 

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How to make a shark go away 

How to make a shark go away is a tough question, but some of the suggestions in the 1964 video do not hold up to more recent scientific research. For example, slapping the water with a cupped hand, shouting in the water, or scratching your inflatable raft or vest might sound more interesting than scary to a curious shark. The same goes for blowing bubbles and throwing scraps of paper in the water.

“Sharks are naturally curious animals, but they’re cautious as well. They investigate something if they don’t think it’s a threat,” he said. “If they do, they avoid it, so all of that may just temporarily distract a shark.”

Being able to see a shark might already be a good sign if you are in the water near one. Lowe pointed out that most shark bite victims do not see the shark before it strikes. 

“The rule of thumb that we always use is when you see a shark, keep your eyes on it and track it,” he said. “Sharks are predators, and what predators like to do is sneak up on their prey. They never like to come head-on. if a shark knows you see it, then a big part of the gig is up. It automatically puts you in what a shark would perceive as a defensive position.”

One thing that definitely will not deter sharks is blowing a whistle underwater, as the narrator suggests. Doing so will not produce any frequencies that are in a shark’s range of hearing, Lowe explained. Trying to somehow outmaneuver a shark also probably will not work, as many shark species “can turn on a dime,” the biologist explained. The shark in the 1964 video may not have been capable of that though.

“The shark that they show in the film over and over again is probably the sickest tiger shark I’ve ever seen,” Lowe said. “It’s all beat up, thin and malnourished, and it looks like it’s blind in its right eye. That’s probably the only footage they could get of a live shark at that time.”

Other techniques mentioned in the 1964 video have proven to be more effective. For example, punching a shark in the nose disorients a shark the same way punching a human in the nose disorients a human, Lowe said. Striking a shark in the eyes or gills is also effective, as does forming a group with other people in the water and kicking outwards because sharks feel less secure around things that appear bigger than them. In fact, Lowe said he just practiced that same technique in recent off-shore water training.

“Size matters,” Lowe said. “If you’re small and it’s big, it has less reason to be afraid. If it’s small and you’re big, that may have an impact on how close it gets.”

‘Big goofs’

Though the 1964 video makes sharks seem as if they are always on the lookout for a human snack, they are not. 

“Sharks evolved millions of years before humans existed and therefore humans are not part of their normal diets,” wrote the National Oceanic and Atmospheric Administration on its website. Instead, sharks usually feed on smaller fish and invertebrates, and while some prey on larger marine mammals, they still don’t usually pursue humans as prey.

“Sharks have been known to attack humans when they are confused or curious,” NOAA wrote. “If a shark sees a human splashing in the water, it may try to investigate, leading to an accidental attack.”

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Lowe has swam with tiger sharks many times, and they’re often “big goofs,” who can even be nudged out of the way and not mind. The marine biologist has learned to understand a shark’s body language to tell when it is agitated, the same way most people can understand a dog is agitated when it bares its teeth, raises its fur or puts its ears down behind its head. 

“You don’t even have to own a dog to know it’s pissed off,” Lowe said. “That’s a body language that stands beyond species because other animals are able to interpret that. Sharks have similar body language but because we’re not aquatic, we did not evolve with those animals, so we can’t interpret their language yet.”

Most humans probably will not spend enough time around sharks to understand their body language, but that is okay because most humans will never encounter a shark. Or at least, they likely won’t be aware of it. And if they do encounter one, they are much more likely to be struck by lightning than be killed in a shark attack. In that spirit, the Federal Aviation Administration has concise advice for downed aviators when it comes to dealing with sharks.

“Chances are, you will probably never see a shark,” the FAA wrote in its Basic Survival Skills for Aviation. “Concentrate your mental energies on something more productive, such as rescue.”

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