Home Environment Slow, Lumbering, and a Row of Gnarly Teeth: Meet the Sand Tiger...

Slow, Lumbering, and a Row of Gnarly Teeth: Meet the Sand Tiger Shark

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Sand tiger shark

Shipwrecks bring a sense of awe and a need for discovery. To see the wrecks up-close brings up a reverence for preservation and protection of their historical significance, as well as a better understanding of how vital the wreck has become to the serving as a habitat for marine life. WWII left many shipwrecks behind along the eastern seaboard of the United States and into the Gulf of Mexico. Biologists, marine biologists, environmentalists, and oceanographers are now finding that these shipwrecks are crucial to the preservation of marine life as they provide a beneficial physical structure on an otherwise sandy ocean floor.

By Selene Muldowney

These wrecks, along with other artificial structures, provide sanctuary for hundreds of marine species, as well as a substrate often not found on the bottom. Not only can divers investigate these wrecks for historical significance and for their incredible array of marine life, but divers may come face to face with a shark.

Fed by the warm and clear waters of the Gulfstream, North Carolina, known as the “Graveyard of the Atlantic”, is home to over 2,000 sunken ships (some record keepers suggest over 5000), as well an important program along the east coast that may prevent the extinction of a vital ocean resident; the sand tiger shark.

Spot A Shark USA, launched in June 2018, is the brainchild of Dr. Avery Paxton and Hap Fatzinger. Dr. Paxton is a marine ecologist and is currently a Postdoctoral Fellow at the South-East Zoo Alliance for Reproduction & Conservation (SEZARC) and a Visiting Scholar at Duke University Marine Lab. Fatzinger is the Director of North Carolina Aquarium at Pine Knoll Shores. This program, driven by the sand tiger shark’s status as a vulnerable species by the International Union for Conservation of Nature (IUCN) Red List of Threatened Species, is a citizen-science program that engages anyone who spends time on, in, and under the water to participate in sand tiger shark research along the Atlantic Coast. Divers, snorkelers, and others are asked to photograph encounters with sand tiger sharks and post their images to the Spot A Shark USA website.

This project is made possible by a number of partners: WildMe, Sand Tiger Shark Consortium (North Carolina Aquariums, SEZARC, Georgia Aquarium, Maritime Aquarium at Norwalk, New York Aquarium / Wildlife Conservation Society, Florida Aquarium, Ripley’s Aquariums), Coastal Studies Institute, Blue Elements Imaging, Duke University, and the Minnesota Zoo Foundation.

Sand tiger sharks, also known as gray nurse sharks, like most sharks use their large, oily livers to control their buoyancy underwater. But, what distinguishes them from the others is their unique habit to come to the surface of the water to gulp air. This air ends up in their stomachs allowing them to control their buoyancy and often float motionless in the water as they watch for prey. Because of their unusual air gulping they are often seen as slow and lumbering as they seemingly glide slowly through the water.

Their lumbering underwater demeanor often allows divers to have extended visual observation with them and an appreciation of their uneven rows of curved teeth beckoning prey to the back of their throats. Despite their ferocious appearance, even with their mouths closed, they are not an aggressive fish and often shy away from human interaction.

Dr. Avery Paxton has a long-standing relationship with citizen science projects and educational programs off the coast of North Carolina fueled by her childhood fascination with shipwrecks and the incredible biodiversity within proximity to them. Prior to taking on this vital program, Dr. Paxton worked in a collaborative effort with University of North Carolina, Discovery Deep, a non-profit with the mission to film and produce work on education programs, several dive instructors, and Bobby Purifoy, owner of Olympus Diving Center in Morehead City, to create and support a citizen-science program to collect observation and fish counts on the AR-330 reef site, sunk in 2015.

Spot A Shark USA was a perfect opportunity to harness the efforts of the divers already exploring these shipwrecks and reefs and combined with Dr. Paxton’s keen awareness of the sand tiger shark’s delicate status off the coast of North Carolina. The program offered her and other marine biologists a chance to better understand the shark’s behaviors. Paxton and Fatzinger created the platform together with their partners to help track the shark movement and behavior over time and learn which coastal habitats sand tiger sharks use during their lives. This information is then used to facilitate management decisions aimed towards conserving sand tiger sharks. Conservation of sand tiger sharks is important because this species is critically endangered in several parts of the world.

“Spot A Shark USA is a partnership with our sister program, Spot A Shark located in Australia. We work collaboratively with our Australian colleagues to share data and information on sharks that we document in the USA and those that our colleagues document in Australia. The goal of Spot A Shark USA is to engage citizens and inspire them to become more involved with shark research and conservation. Citizen scientists become detectives – collecting evidence that our Spot A Shark USA team processes to help solve mysteries of sand tiger sharks,” states Dr. Paxton.

Fatzinger became directly involved with the conservation of sand tiger sharks in 2014. Through his work, in conjunction with SEZARC and several other Association of Zoos and Aquariums (AZA) aquarium members, they launched a massive program to focus on sustainability of sand tiger sharks in the wild and in human care. Fatzinger worked with colleagues in Australia utilizing the original version of the Spot A Shark program to better understand movement patterns of sand tigers (called grey nurse sharks in Australia), a critically endangered population, and how human fishing activities impacted the remaining animals.

Fatzinger saw an opportunity, “I saw the population off NC as a great opportunity to engage our recreational dive community in active science and become more engaged with shark conservation and ocean health on a local, regional and global scale.  Spot A Shark USA has been in development for several years but really took off once Avery joined the team.”

Globally, sand tiger sharks are considered “Vulnerable,” meaning there is a high risk of extinction.  There are populations around the world that are considered critically endangered; however, off the East Coast of the United States, they are managed as a “Species of Concern” by the National Marine Fisheries Service.  Sand tiger sharks have declined over 75% over the past several decades, specifically in the 1980’s and 1990’s due largely to unregulated fishing.

“This really describes our need to better understand the populations, and the data we are collecting will help.  We hope our findings will reveal opportunities for regulators to better manage populations that are in serious jeopardy. We have been collaborating with our Australian colleagues since day one.  Through funds we have raised, we have been able to upgrade their systems and work to advance the processing power for both our system and their system in the future.  In addition, all the data contributed is shared by researchers and supports global population needs.  We’ve had a few preliminary discussions with dive operators and researchers in South Africa regarding their “ragged tooth” sharks (sand tigers) and the potential of engaging with that population in the future,” emphasizes Fatzinger.

This program has been well received by local divers and charters like Bobby Purifoy from Olympus Dive Center, who is no stranger to diving around the sand tiger sharks. An active member of East Carolina Artificial Reef Association (ECARA) Purifoy is an avid supporter of environmental causes and sustainability of marine habitats. His work with the 2015 sinking of the James J. Francesconi at the offshore reef site AR-330 encouraged his desire to assist Dr. Paxton and Fatzinger in their efforts to find and identify the sand tiger sharks.

Purifoy takes divers to explore the shipwrecks and observe the sand tiger sharks. They have identified a number of wrecks most popular with the sharks and now a destination for the citizen scientists who take pictures and often want to track “their shark” movements. Historic shipwrecks, including the Papoose, the Atlas, the Caribsea, as well as artificial reefs including the Spar and Aeolus, are often populated by sand tiger sharks as well large groups of spadefish, baitfish, amberjack, and other fish.

“Unlike shark dives in other destinations, we do not chum the waters or feed the sharks. Rather, it is a unique opportunity for divers to observe these beautiful and fascinating animals in their natural environment,” states Purifoy.

The overall hope is to increase the awareness and appreciation for these vulnerable animals and their ocean habitats.  Through engaging divers in the science, and providing an interactive website, the team will lead citizen scientists (and the general public) on a journey to understand how the sand tiger sharks use their aquatic habitats, the threats they face, and how to support the long-term health of the oceans.

Fatzinger reminds us to become better stewards, “Be responsible stewards of our environment; reduce your use of natural resources; support sustainably harvested seafood (Seafood Watch is a great reference); visit an AZA accredited zoo or aquarium and learn more about conservation and research activities that are underway to protect wildlife and wild places; and reduce single-use plastics in your life.”

Get involved and become a citizen scientist!

Here is how:

Photograph sharks

Citizen scientists can take photographs of sand tiger sharks and upload their photos to the Spot A Shark USA website (SpotASharkUSA.com).

Ensure photos show spots

The most valuable photos are photos taken at right angles to the shark so that spots along the sides of the shark are visible.

Follow sharks

Citizen scientists can follow their sharks, as well as other sighted sharks, over time.

Adopt a shark!

If citizen scientists want, they can adopt a sand tiger shark and name their adopted shark.

Important note: The program does NOT condone removing sharks from the water for photography. They will NOT accept photos showing illegal handling or mishandling of sharks.

Want to learn more? Please visit Spot A Shark USA website: spotasharkusa.com