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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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Animals
Atlanta Shelters Give Pups a Temporary Home for the Holidays
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The holidays are looking a little brighter for adoptable dogs from two animal shelters in Atlanta, Georgia. As ABC News reports, a new program called Home for the Pawlidays is providing temporary homes to longer-term residents of Fulton County Animal Services and DeKalb County Animal Services for the week of Thanksgiving.

The initiative was organized by Atlanta's LifeLine Animal Project, a local group dedicated to providing healthcare and homes to shelter dogs. The dogs that were chosen for the project may be older, have special health needs, or other issues that make it more difficult to find them forever homes.

But from November 18 to 25, the dogs are getting to spend time away from the shelter and in the homes of loving foster families.

“We were thinking, everyone gets a break from work, and they should get a break from the shelter,” LifeLine’s public relations director Karen Hirsch told ABC News.

Some caretakers have already fallen in love with their four-legged house guests. Foster Heather Koth told ABC that she hadn’t been considering adoption, but after meeting Missy the shelter dog, she now plans to foster her until she has a permanent home or possibly adopt the dog herself.

And for the dogs that can’t be kept by their temporary owners, just a week of quality playtime and sleeping in a real bed can make a huge impact. You can check out photos of the pets who are benefiting from the program this week below.

[h/t ABC News]

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25 Things You Didn't Know About Turkeys
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iStock

Most of us probably associate turkey with a sumptuous Thanksgiving spread, but there’s a lot more to the big bird than how delicious it is alongside your grandma’s famous cranberry sauce. Here are a few bits of knowledge you can drop over the dinner table—when you’re not fighting with your family over white meat or dark meat, that is.

1. THE NORTH AMERICAN WILD TURKEY POPULATION WAS ALMOST WIPED OUT.

Wild turkey
iStock

Wild turkeys once roamed the continent en masse, but by the early 20th century, the entire U.S. population had been whittled down to a mere 30,000 due to hunting and the destruction of their woodland habitats. In the 1940s, many of the remaining birds were relocated to parts of the U.S. with recovering woodlands so the turkeys could repopulate. Despite these efforts, by 1973, there were still just 1.5 million wild turkeys in North America. Today, that number is up to about 6 million.

2. TURKEY APPENDAGES ARE LIKE MOOD RINGS.

Wild turkey
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The dangly appendage that hangs from the turkey’s forehead to the beak is called a snood. The piece that hangs from the chin is the wattle. These fleshy flaps can change color according to the turkey’s physical and mental health—when a male turkey (called a tom, of course) is trying to attract a mate, the snood and wattle turn bright red. If the turkey is scared, the appendages take on a blue tint. And if the turkey is ailing, they become very pale.

3. TURKEYS CAN FLY.

Wild turkey in flight
iStock

Well, domestic turkeys that are bred to be your Thanksgiving centerpiece can’t. They’re too heavy. But wild turkeys can, reportedly at speeds up to 55 miles per hour. Though they don’t go very far—usually less than 100 yards—wild turkeys are among the five largest flying birds in the world. They’re in good company: Others on the list include the swan and the albatross.

4. THEY CAN ALSO SWIM.

Wild turkey drinking water
iStock

Turkeys don’t swim often, it seems, but they can, by tucking their wings in, spreading their tails, and kicking. In 1831, John James Audubon wrote, “I have been told by a friend that a person residing in Philadelphia had a hearty laugh on hearing that I had described the Wild Turkey as swimming for some distance, when it had accidentally fallen into the water. But be assured, kind reader, almost every species of land-bird is capable of swimming on such occasions, and you may easily satisfy yourself as to the accuracy of my statement by throwing a Turkey, a Common Fowl, or any other bird into the water.”

5. TURKEY POOP CAN TELL YOU A LOT.

A handler picking up turkey poop at the White House Turkey Pardon in 2013.

The next time you happen across turkey poop—which happens all the time, we know—take a closer look at it. If the droppings are shaped like a “J,” they were left there by a male turkey. Spiral-shaped poo? The culprit is female.

The citizens of Pilot Rock, Oregon, probably don’t much care about the shape of the stuff, but more about the quantity of it. Earlier this year, Pilot Rock turned to the Oregon Department of Fish and Wildlife (ODFW) for help combating a flock of 50 to 70 wild turkeys that would periodically invade the town, destroy gardens, perch in trees, and poop on pickup trucks. The ODFW offered several solutions, but as far as we know the turkeys still rule the roost at Pilot Rock.

6. TURKEY PROBABLY WASN'T ON THE PILGRIMS' MENU.

A recreation of the Pilgrims' first settlement
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Thanks to historical records, we know for sure that the Wampanoag brought deer, and the English brought fowl—likely ducks and geese.

7. BEN FRANKLIN DIDN'T REALLY WANT THE TURKEY TO BE OUR NATIONAL BIRD.

A drawing of Ben Franklin.
Getty / Hulton Archive / Handout

You may have heard that at least one of our Founding Fathers lobbied hard to make the turkey our national symbol instead of the noble bald eagle. That’s not quite true, but in a letter to his daughter, he did expound on the character of each, which may be where the rumor got started:

“For my own part I wish the Bald Eagle had not been chosen the Representative of our Country. He is a Bird of bad moral Character. He does not get his Living honestly. You may have seen him perched on some dead Tree near the River, where, too lazy to fish for himself, he watches the Labour of the Fishing Hawk; and when that diligent Bird has at length taken a Fish, and is bearing it to his Nest for the Support of his Mate and young Ones, the Bald Eagle pursues him and takes it from him.

“With all this injustice, he is never in good case but like those among men who live by sharping & robbing he is generally poor and often very lousy. Besides he is a rank coward: The little King Bird not bigger than a Sparrow attacks him boldly and drives him out of the district. He is therefore by no means a proper emblem for the brave and honest Cincinnati of America who have driven all the King birds from our country…

“I am on this account not displeased that the Figure is not known as a Bald Eagle, but looks more like a Turkey. For the Truth the Turkey is in Comparison a much more respectable Bird, and withal a true original Native of America… He is besides, though a little vain & silly, a Bird of Courage, and would not hesitate to attack a Grenadier of the British Guards who should presume to invade his Farm Yard with a red Coat on.”

8. ANOTHER TURKEY FAN: ALEXANDER HAMILTON.

Portrait of Alexander Hamilton
Wikimedia Commons // Public Domain

Yep, A. Ham liked turkey. In fact, he thought eating turkey was practically a god-given right, and once remarked that "No citizen of the U.S. shall refrain from turkey on Thanksgiving Day."

9. TEDDY ROOSEVELT BELIEVED THE BIRDS WERE CUNNING PREY.

Teddy Roosevelt on a hunting trip in Africa.
Getty / Hulton Archive / Stringer

Ol’ TR may have been accustomed to hunting big game, but wild turkeys held a special place in his heart. He believed they were every bit as challenging to hunt as deer. In his 1893 book Hunting Trips of a Ranchman and the Wilderness Hunter, he wrote, “The wild turkey really deserves a place beside the deer; to kill a wary old gobbler with the small-bore rifle, by fair still-hunting, is a triumph for the best sportsman.”

10. WILD TURKEYS HAVE BETTER VISION THAN YOU DO.

Close up of wild turkey's head
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Their fantastic vision is probably one reason Teddy Roosevelt found turkeys such a challenge to hunt. They can detect motion from many yards away, have vision three times greater than 20/20, and have peripheral vision of about 270 degrees. Ours, comparatively, is only 180. And although turkeys can’t see in 3D, they can see UVA light, which helps them better identify predators, prey, mates, and food.

11. THE TOP TURKEY-PRODUCING STATE MAY SURPRISE YOU.

Domesticated turkeys on a farm
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You may know Minnesota for producing Prince, the Mall of America, and Target. But we also have the Land of 10,000 Lakes to thank for our Thanksgiving turkeys. According to the Minnesota Turkey Growers Association, approximately 46-48 million turkeys are produced in Minnesota every year. In fact, it’s where the turkey that receives a presidential pardon hails from every year. Speaking of which ...

12. THE PRESIDENTIAL TURKEY PARDON MAY DATE BACK TO ABE LINCOLN.

President Barack Obama pardons a turkey in 2011.
Getty / Mark Wilson / Staff

Officially, the tradition of the sitting president of the United States pardoning his Thanksgiving turkey dates back to John F. Kennedy, who decided to let his gift from the National Turkey Federation off the hook. But he wasn't the first president to let a turkey go free: When Abraham Lincoln’s son Tad befriended one of the birds intended for Christmas dinner in 1863, kind-hearted Abe granted it a stay of execution.

13. THE FIRST TV DINNER MEAL: THANKSGIVING LEFTOVERS

Thanksgiving TV dinner
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In 1953, Swanson ended up with 10 train cars full of frozen turkeys—260 tons of them—when an overzealous buyer ordered too many turkeys for the holidays. Salesman Gerry Thomas solved the problem by ordering 5,000 aluminum trays and setting up an assembly line of workers to scoop dressing, peas, and sweet potatoes into the compartments. Slices of turkey rounded out the meal, which Swanson sold for 98 cents. The idea was a hit: The following year, 10 million turkey TV dinners were sold.

14. NATIONAL TURKEY LOVERS’ MONTH ISN’T WHEN YOU THINK.

Grilled meats on a silver tray
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Everyone eats turkey in November and December, so there’s not a lot of need for extra poultry promotion during those months. If you want to celebrate National Turkey Lovers’ Month, you’ll have to do it in June with some turkey brats and burgers on the grill.

15. THE TURKEY YOU’LL BE EATING IS PROBABLY ABOUT 18 WEEKS OLD.

Roasted turkey on a platter
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That’s how long it typically takes the birds to grow to maturity, which is when they’re usually slaughtered.

16. THERE WAS ALMOST A TURKEY SIDEKICK IN POCAHONTAS.

Loren Javier via Flickr // CC BY-ND 2.0

At one point, Disney thought Pocahontas needed a little comic relief, so they hired John Candy to voice a wisecracking woodland fowl named Red Feather. Sadly, Candy passed away while the logistics were being worked out, so animators dropped the turkey entirely and opted for a clever raccoon named Meeko.

17. NOT ALL TURKEYS GOBBLE.

Close up shot of a wild turkey
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If you hear a turkey making the distinctive noise we all associate with them, then you’re hearing a male communicating with his lady friends up to a mile away. Females make a clicking sound instead of a gobble.

18. IF YOU DON’T EAT TURKEY AT THANKSGIVING, YOU’RE IN THE MINORITY.

A black and white photo of a family gathering around the table as the mother brings in a turkey.
Getty / Evans / Stringer

According to the National Turkey Federation, 88 percent of Americans eat turkey at Thanksgiving.

19. TURKEY CRAVINGS CAUSED A SPIKE IN KFC SALES IN JAPAN.

A large Kentucky Fried Chicken sign
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When KFC opened its first stores in Japan in the 1970s, the company was surprised to find that sales soared during the holidays. The phenomenon stymied executives since most of Japan celebrates neither Thanksgiving nor Christmas. It was later discovered that foreigners craving holiday turkey had decided that KFC’s chicken was the next best thing. After the company figured this out, they played up the association with their “Kurisumasu ni wa kentakkii!” campaign—“Kentucky for Christmas.” It worked on tourists and locals alike, and today, Christmas Eve is still the highest-selling day for KFC Japan.

20. THERE IS PROPER TURKEY TERMINOLOGY.

A flock of turkeys on a farm with one staring directly into the camera.
Getty / Cate Gillon / Staff

You probably know that a group of turkeys is a flock, but they can also properly be called a “rafter.” And should you want to call baby turkeys something a little more precise, you can call them “poults.”

21. THE MAYA USED TURKEYS AS SACRIFICIAL OFFERINGS.

A Maya tripod plate featuring a bird
Los Angeles County Museum of Art via Wikimedia Commons // Public Domain

Archaeologists have found vases dating from 250-800 CE that have turkeys depicted on them. According to University of Wisconsin-Milwaukee art historian Andrea Stone, "turkeys were quintessential animals for feasting and for sacrificial offerings." The Maya even crafted tamales shaped like the birds.

22. DURING THE ‘70S, YOU COULD CALL JULIA CHILD FOR TURKEY ADVICE ON THANKSGIVING.

Julia Child in her kitchen in 1978
Lynn Gilbert via Wikimedia Commons // CC BY-SA 4.0

Even when she was at peak popularity, the famous chef refused to remove her phone number from public listings. According to friends, complete strangers would call Child on Thanksgiving to ask for advice on cooking the perfect turkey. Julia always answered the phone, and typically told callers whatever they needed to hear to get them to relax and enjoy the holiday. She even told some amateur cooks that turkey was best served cold anyway.

23. BIG BIRD IS A TURKEY.

Big Bird and Elmo at the Macy's Thanksgiving Day Parade.
Getty / Matthew Peyton / Stringer

Well, according to Sesame Street, he’s actually a canary—but his plumage makes him a turkey. The good people at American Plume & Fancy Feather provide Sesame Street with several thousand turkey feathers per costume to make sure Big Bird looks soft and fluffy.

24. THE BIRD IS NAMED AFTER THE COUNTRY.

Hagia Sophia in Istanbul, Turkey
iStock

But the whole thing was a mistake. Centuries ago, the English began to import a rather tasty bird, now known as a helmeted guinea fowl, from Madagascar. But they didn’t know it was from Africa. Because it was imported to Europe from merchants in Turkey, the English believed the birds were also Turkish.

Later, when the Spanish arrived in the New World, they discovered Meleagris gallopavo—the wild turkey. It was delicious, so they started importing it back to Europe. Europeans thought it tasted like the “turkey” guinea fowl they had been enjoying, so they called it the same thing.

25. WHAT, EXACTLY, IS DARK MEAT?

Roasted turkey legs on a piece of butcher paper
iStock

It’s just a different type of muscle than white meat. White meat is the result of glycogen, which doesn't need much oxygen from the blood because the muscles it fuels only require short bursts of energy. Dark meat, however, is found on wings, thighs, and drumsticks—muscles that are used for long periods of time and require more sustainable energy. It’s made dark by the proteins that convert fat into energy.

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