Discovery Channel
Discovery Channel

How Scientists Built a Shark-Following Robot for Shark Week

Discovery Channel
Discovery Channel

For all we know about sharks, there's still a lot we don't know about these animals that both fascinate and terrify us. Traditional tracking methods like satellite and acoustic tags have shed some light on shark behavior, but even they have their limitations.

That's where Shark Cam, an autonomous underwater vehicle, comes in. "A few years [ago], I was working with a scientist who loved the idea of trying to find out what some of these fish that we track do when we can’t follow them because they’re out of reach or they go deep or we disturb them when we get in the water," says marine biologist Greg Skomal. "We thought it’d be really interesting to develop some kind of robot that could track marine animals, specifically sharks. One of the principals at Big Wave Productions [which produces shows for Shark Week] was super excited about the concept and propelled it upwards to Discovery, and they loved it. So with their support, we were able to actually make this come to fruition."

The autonomous underwater vehicle (AUV) was developed by Skomal and scientists at the Oceanographic Systems Laboratory at Woods Hole Oceanographic Institution. It was deployed from a boat off of Chattam, Massachussets, last year, where it followed great white sharks as they swam along the coast. Shark Cam makes its debut in the Shark Week special "Return of Jaws" tonight at 9 p.m. EST on the Discovery Channel; we talked to Skomal about developing the robot and what it revealed that traditional tracking methods did not.

How long did it take to build and deploy Shark Cam?

We started the project in 2011, and were able to do some field trials in late 2011, and we had a pretty functional vehicle by the summer of 2012. So about a year of solid development. Most of that was software modifications by the engineers who run these robotic underwater vehicles.

When you’re building something like this, are you working from an existing platform or are you starting from scratch?

The Oceanographic Systems Laboratory at Woods Hole Oceanographic Institution has an existing group of vehicles that are autonomous—they’re completely untethered to the boat, and they can be programmed to do a variety of missions. So really, all we had to do was modify the software of one their existing vehicles in order to get it to follow a live shark.

It sounds simple, but it wasn’t. It was a partnership—[between the engineers and] me, having tracked fish for years, trying to give them a sense of what we anticipate the behavior of the shark to be, so that the vehicle can adjust to it. It’s one thing to have a vehicle go in a straight line, or even mow a lawn—back and forth, back and forth—but to have it adjust to the behavior of a live animal is a most complex process.

What kind of behaviors would they be adjusting for?

Changes in three-dimensional movement. Up, down, sideways, back, forth—you name it. Very few live animals swim in a straight line at one depth. So it had to basically adapt to random movements in three-dimensional space.

What technology did you outfit the robot with?

There were four cameras on Shark Cam—it was specially designed to carry three of those, and one mounted on top. It's battery-powered, which limits its life, but that’s fine, we can expand on that. It is modular in the sense that we can add components to it that do various kinds of things that we did not do [on this mission], like collect oceanographic data. It communicates with a transponder that we put on the shark to follow it and navigate and recreate the track of the animal.

We actually added a rear-facing camera, but because of the fine balance on the vehicle itself—it’s a torpedo and it has to be extremely hydrodynamic—throwing the extra camera on slowed it down. So that’s something that we have to develop in the next phase of this operation.

Robot with a view. Photo courtesy of the Discovery Channel.

When you decided you were going to take the Shark Cam out and put in the water and send it after a shark, you guys had to go out and tag the shark first. How did the robot work in conjunction with the acoustic tags?

We’ve been tracking white sharks with a variety of technology off the coast of Cape Cod for the last four summers. So [tagging the sharks was] almost the easiest part, since we’d already done the [research and development] to get that done. Once we got the transponder on the shark, the AUV was set to go.

Most acoustic transmitters emit a ping, and the ping is picked up by people in the tracking vehicle, so we can track the fish. But this acoustic tag is a transponder, so it has two-way communication between the vehicle itself and, in essence, the shark. So we can basically have a conversation that provides for highly precise navigation and mapping of three-dimensional movement. And that really is a step forward, because it’s not just passive acoustics where you’ve got a vehicle trying to just listen for something. [The AUV] was actually listening and communicating with [the tag].

We had to program the vehicle so that it could make decisions—very simple cause and effect decisions based on where the shark was, to follow it. We ended up getting a vehicle that can give us very precise tracks of the animal.

Were there any glitches you had to work out?

There was a whole series of glitches. The transponder itself is larger than we want it, but the funding simply wasn’t there to miniaturize it. So we had to use what we had. It turns out the orientation of the existing transponder design had to be vertical in the water column, which is absolutely counter to normal hydrodynamics. We had to figure out a way to get it to tow vertically on the shark, and that took a few days working with our tagging crew and the engineers. And that would allow for a stronger signal so that the AUV could actually keep up with the shark in shallow water.

We’re also in the natural environment. Where these white sharks hang out is a very dynamic area in terms of tide and current. So in many ways, we’re up against trying to get a vehicle that can only go, you know, six miles an hour to keep up with a shark that was swimming steadily at five miles an hour. And then it was the fine-tuning of the vehicle so that it could stay with the shark and not lose it.

How did the sharks react to it?

Jokingly, I told the engineers that once this big white shark sees this vehicle, painted bright yum-yum yellow, it was going to turn around and just eat it. Most would think that this voracious animal that is considered to be one of the most dangerous one on earth would not like to be followed so closely. So these guys got nervous every time the AUV got in close proximity to a shark.

But the shark completely ignored it. [At one point,] the shark actually turned around and did a big loop and started following the AUV, which I thought was fantastic. The AUV couldn’t do anything about it—it was hearing the shark behind it, and a major limitation of the technology is that it can’t do hairpin turns and quick circles. So that made for some good humor.

What did you learn by deploying this robot that you couldn’t learn just from using acoustic tags or satellite tags?

Every tag in technology has its ups and downs, and there’s no silver bullet when it comes to tags that gives you high resolution, broad scale, and fine-scale data on movement. Satellite tags are really good for looking at broad-scale movement—where the shark goes in broad migratory patterns. It doesn’t tell you a lot about fine-scale behavior.

Acoustic tags will tell you a little bit about fine-scale behavior, but only in the sense that you know where the shark is at any given time. One of the problems with the technology of acoustic tags—prior to us doing this—was instead of sending a robot after a shark, you follow the shark with your boat. And that’s usually limited by weather considerations, fuel, compatibility of crew members, provisions, all those things that can come up and go wrong. And the boat’s track doesn’t necessarily reflect the shark’s track, because the shark is going to be somewhere within a quarter or a half a mile from the boat. And it’s really hard to get a good, precise estimate of the actual movements of the shark in three-dimensional space using traditional tracking methods.

With the ability to send robots after the shark, you’re going to increase the precision of your tracking so you’ll know exactly what the shark did in three-dimensional space—the depth of water, the depth of the shark—and you’re collecting data at the same time over that same path. The vehicles can carry instrumentation on them—the simplest being water temperature, to complex instrumentation that measures current and tide—so you can determine whether the shark is swimming upstream or downstream. You can look at dissolved oxygen, so you can get a sense of what the minimal oxygen requirements of the shark are. You can also add other kinds of instrumentation that’ll answer questions about the habitat in which the shark lives.

So it’s a huge step forward—and when you throw cameras on the whole thing, you even have the potential for real behavioral observation: To see what the shark is doing. Let’s say it stops swimming and just stays in one area. If we approach it and put divers in the water, that’s going to spook the shark—and very few divers want to jump on top of a white shark to begin with. Or you speed up on it on a boat and you try to see what the shark is doing, but what if it’s 30 feet underwater? You can’t see what it’s doing. You send Shark Cam out, and you can record what’s going on in that area.

So the robot is a proxy for what we can’t do, and I think it’s a huge step forward in terms of advancing science and adding a new tool for marine scientists.

Have you used Shark Cam since?

We have not deployed the Shark Cam since last summer. The next step is going back to the drawing board—raising funding to tweak it and take it to the next level.

What's the next level?

The next level for us is to improve upon and learn from what we’ve already done. It’s a real solid analysis of the data, it’s fine-tuning the software to take into account sudden modifications in the shark’s behavior. It’s probably to integrate the camera systems a little better with the AUV so that we may be able to control them—turn them on, turn them off. It’s energy budgeting. And it’s really miniaturizing the transponder so that we can put it on much smaller sharks and maybe broaden its applicability.

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Roadside Bear Statue in Wales is So Lifelike That Safety Officials Want It Removed
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Wooden bear statue.

There are no real bears in the British Isles for residents to worry about, but a statue of one in the small Welsh town of Llanwrtyd Wells has become a cause of concern. As The Telegraph reports, the statue is so convincing that it's scaring drivers, causing at least one motorist to crash her car. Now road safety officials are demanding it be removed.

The 10-foot wooden statue has been a fixture on the roadside for at least 15 years. It made headlines in May of 2018 when a woman driving her car saw the landmark and took it to be the real thing. She was so startled that she veered off the road and into a street sign.

After the incident, she complained about the bear to highways officials who agreed that it poses a safety threat and should be removed. But the small town isn't giving in to the Welsh government's demands so quickly.

The bear statue was originally erected on the site of a now-defunct wool mill. Even though the mill has since closed, locals still see the statue as an important landmark. Llanwrtyd Wells councilor Peter James called it an "iconic gateway of the town," according to The Telegraph.

Another town resident, who wished to remain anonymous, told The Telegraph that the woman who crashed her car had been a tourist from Canada where bears are common. Bear were hunted to extinction in Britain about 1000 years ago, so local drivers have no reason to look out for the real animals on the side of the road.

The statue remains in its old spot, but Welsh government officials plan to remove it themselves if the town doesn't cooperate. For now, temporary traffic lights have been set up around the site of the accident to prevent any similar incidents.

[h/t The Telegraph]

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10 Scientific Benefits of Being a Dog Owner
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The bickering between cat people and dog people is ongoing and vicious, but in the end, we're all better off for loving a pet. But if anyone tries to poo-poo your pooch, know that there are some scientific reasons that they're man's best friend.

1. YOU GET SICK LESS OFTEN.

Dog snuggling on a bed with its person.
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If cleaning commercials are to be believed, humanity is in the midst of a war against germs—and we shouldn't stop until every single one is dead. In reality, the amount of disinfecting we do is making us sicker; since our bodies are exposed to a less diverse mix of germs, our entire microbiome is messed up. Fortunately, dogs are covered in germs! Having a dog in the house means more diverse bacteria enters the home and gets inside the occupants (one study found "dog-related biodiversity" is especially high on pillowcases). In turn, people with dogs seem to get ill less frequently and less severely than people—especially children—with cats or no pets.

2. YOU'RE MORE RESISTANT TO ALLERGIES.

Child and mother playing with a dog on a bed.
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While dog dander can be a trigger for people with allergies, growing up in a house with a dog makes children less likely to develop allergies over the course of their lives. And the benefits can start during gestation; a 2017 study published in the journal Microbiome found that a bacterial exchange happened between women who lived with pets (largely dogs) during pregnancy and their children, regardless of type of birth or whether the child was breastfed, and even if the pet was not in the home after the birth of the child. Those children tested had two bacteria, Ruminococcus and Oscillospira, that reduce the risk of common allergies, asthma, and obesity, and they were less likely to develop eczema.

3. YOU'LL HAVE BETTER HEART HEALTH.

Woman doing yoga with her dog.
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Everything about owning a dog seems to lend itself to better heart health. Just the act of petting a dog lowers heart rate and blood pressure. A 2017 Chinese study found a link between dog ownership and reduced risk of coronary artery disease, while other studies show pet owners have slightly lower cholesterol and are more likely to survive a heart attack.

4. YOU GET MORE EXERCISE.

Person running in field with a dog.
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While other pets have positive effects on your health as well, dogs have the added benefit of needing to be walked and played with numerous times a day. This means that many dog owners are getting 30 minutes of exercise a day, lowering their risk of cardiovascular disease.

5. YOU'LL BE HAPPIER.

Woman cuddling her dog.
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Dog owners are less likely to suffer from depression than non-pet owners. Even for those people who are clinically depressed, having a pet to take care of can help them out of a depressive episode. Since taking care of a dog requires a routine and forces you to stay at least a little active, dog owners are more likely to interact with others and have an increased sense of well-being while tending to their pet. The interaction with and love received from a dog can also help people stay positive. Even the mere act of looking at your pet increases the amount of oxytocin, the "feel good" chemical, in the brain.

6. YOU HAVE A MORE ACTIVE SOCIAL LIFE.

Large bulldog licking a laughing man.
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Not only does dog ownership indirectly tell others that you're trustworthy, your trusty companion can help facilitate friendships and social networks. A 2015 study published in PLOS One found that dogs can be both the catalyst for sparking new relationships and also the means for keeping social networks thriving. One study even showed that those with dogs also had closer and more supportive relationships with the people in their lives.

7. YOUR DOG MIGHT BE A CANCER DETECTOR.

Man high-fiving his dog.
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Your dog could save your life one day: It seems that our canine friends have the ability to smell cancer in the human body. Stories abound of owners whose dogs kept sniffing or licking a mole or lump on their body so they got it checked out, discovering it was cancerous. The anecdotal evidence has been backed up by scientific studies, and some dogs are now trained to detect cancer.

8. YOU'LL BE LESS STRESSED AT WORK.

Woman working on a computer while petting a dog.
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The benefits of bringing a dog to work are so increasingly obvious that more companies are catching on. Studies show that people who interact with a pet while working have lower stress levels throughout the day, while people who do not bring a pet see their stress levels increase over time. Dogs in the office also lead to people taking more breaks, to play with or walk the dog, which makes them more energized when they return to work. This, in turn, has been shown to lead to much greater productivity and job satisfaction.

9. YOU CAN FIND OUT MORE ABOUT YOUR PERSONALITY.

Man running in surf with dog.
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The kind of dog you have says a lot about your personality. A study in England found a very clear correlation between people's personalities and what type of dogs they owned; for example, people who owned toy dogs tended to be more intelligent, while owners of utility dogs like Dalmatians and bulldogs were the most conscientious. Other studies have found that dog owners in general are more outgoing and friendly than cat owners.

10. YOUR KIDS WILL BE MORE EMPATHETIC.

A young boy having fun with his dog.
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Though one 2003 study found that there was no link between pet ownership and empathy in a group of children, a 2017 study of 1000 7- to 12-year-olds found that pet attachment of any kind encouraged compassion and positive attitudes toward animals, which promoted better well-being for both the child and the pet. Children with dogs scored the highest for pet attachment, and the study notes that "dogs may help children to regulate their emotions because they can trigger and respond to a child's attachment related behavior." And, of course, only one pet will happily play fetch with a toddler.

A version of this story originally ran in 2015.

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