Why scientists want your SHARK pictures

Sand tiger sharks are using shipwrecks off the coast of North Carolina more often, and scientists want to find out why. So they're asking divers to take pictures of these docile sharks and upload them to a special website that can track them using their tell-tale spots.

PINE KNOLL SHORES—The Great White Shark: the shark from the movie Jaws, and the shark that is always featured on Shark Week crashing into the diving cage, is the image of the shark that always comes to mind. The sand tiger shark is probably a close second.

“Sand tiger sharks are these iconic sharks with a ragged toothy grin and spots on their sides that live in large numbers off the coast of North Carolina,” explains Avery Paxton, Ph.D., a marine ecologist and a postdoctoral fellow at Southeast Zoo Alliance for Reproduction and Conservation. “Sand tiger sharks hang out on the shipwrecks that we have off of our coast. And we have large numbers of sand tigers sharks because it is known as the Graveyard of the Atlantic since there are so many shipwrecks.”

It is quite an image, as a shark with a toothy grin silently moves out of the shadows of a shipwreck. Sand Tiger sharks are found on shipwrecks from New England to Florida and in the Gulf of Mexico. The sharks are most likely drawn to the wrecks by the large numbers of fish that live on the wrecks. The fish are food. But beyond that, the sand tiger shark is a mystery.

“The big question we need to figure out is why all of those sand tiger sharks ended up in our watery back yard,” added Paxton. “And there are numerous schools of thought. Some people think the sharks are using the wrecks as a rest stop along their migration route. Some others think sand tiger sharks might be staying here year round. So that’s where this citizen science program comes in.”

The program is called Spot a Shark USA. Researchers are asking divers, anglers, and anybody who comes in contact with a sand tiger shark to take a photo of it and upload the photo to a special website.

At first, the idea of taking a photograph of a shark might sound odd. The initial reaction upon seeing a shark would be too swim away. But sand tiger sharks are very docile. The key for a photograph to be used by the Spot A Shark USA program is that it needs to show enough of the side of the shark so that the spots are spots visible. That’s because the spots on a sand tiger shark are like human fingerprints. Each shark has a unique set of spots. In addition, the spots on sand tiger sharks stay constant and are visible at birth. That combination makes the spots a perfect way to identify a shark and, photos are submitted, track the shark’s movements. Researchers take the uploaded photos and electronically mark the spots as well as the fins on the shark. A green dot is inserted over each spot.

. Once each spot and the fins are mapped, the photo is reloaded into an image database. The computer software then compares the newer photo with all of the other shark photos that citizen scientists have submitted in the system. It then alerts researchers if the shark is already identified or if it is a completely new shark. Researchers can then track the shark’s movements.

“I’m hoping this program sheds some light on not only why the sand tiger sharks are here but also starts to ease people’s fear of sharks,” said Hap Fatzinger, director of the North Carolina Aquarium at Pine Knoll Shores. “The movie Jaws started this fear of sharks and the ocean.”

So it’s no surprise that Sand Tiger sharks are a popular attraction at the North Carolina Aquarium in Pine Knoll Shores. The aquarium is collaborating with Spot a Shark USA research in hopes of correcting some of the myths surrounding sharks.

“Most people don’t realize the complexity, the sensitivity, the diversity, of those marine environments and how valuable they are to everything we do, from recreation dollars to tourism money to commercial and recreational fishing industry which supports and supplies the food which we need,” adds Fatzinger. “And sharks are an important part of that environment. If we don’t have healthy oceans and sustainable fisheries we’re all going to lose from that. So our role here at the aquarium is to inspire people not only to learn more but also to take action for these animals in the oceans for all of our well being.”

Bobby Purifoy is curious about the changes he is witnessing in the ocean. Purifoy started diving when he was ten years old. He owns the Olympus dive center in Morehead City now. One of the biggest changes he’s noticed is the arrival of sand tiger sharks.

“The sand tiger sharks are there but they don’t bother you,” said Purifoy. “They come in check you out and if you don’t have anything they’re interested in they are on their way.” He’s already submitted a few photos to the Spot a Shark USA program website. “Diving in North Carolina means something different everyday,” adds Purifoy. “We have four seasons in North Carolina and we also have hurricanes and doldrums, we have calm and we have rough, we have cold and we have hot, we have gulf stream and we have Labrador current, we have shipwrecks and we have reefs, we have rocks and we have sand. It’s different everyday and the sharks are just another part of that. But I would like to know why they haven’t been here all along.”

Paxton is a leading researcher on the Spot a Shark USA program and she’s excited by the amount of interest the project has generated. She’s hoping the wide range of ocean that citizen scientists can cover will help answer questions about the sand tiger sharks.

“Even a few researchers can’t cover the amount of territory that citizen scientists can so that should help provide a wider view of what sand tiger sharks are doing,” said Paxton. “Sharks are top predators and that includes sand tiger sharks in many systems, including off our coast, and top predators really help insure that our coastal ocean remains healthy. So many people in North Carolina depend on the ocean, so it’s important we understand what is happening in the ocean and why the sharks have appeared in such large numbers.”