![]() (Photo by Shawn Harper) We work closely with many people in the NC dive community. Sand tiger sharks give birth to live pups, but we do not know where females go to give birth. We believe NC is an important area for female sharks, but little is known about where and when mating occurs. The large belly and mating scars around the pectoral fin indicate this female may be pregnant. I am curious…where did they hang out before there were so many shipwrecks? (Photo by Mike Gherkin) The spots along the sides are clearly visible on this female photographed at the wreck of the Dixie Arrow, off the Outer Banks of North Carolina. We are using the data from Spot A Shark USA to learn more about how sand tigers use wreck habitats. Sand tiger sharks are often found in large aggregations at some sites, but presence and abundance vary seasonally. Shipwrecks off the North Carolina coast – like the USCGC Spar shown here – are important habitat for many fish species. Repeat records of even more individual sand tiger sharks will help track their movement and behavior over time. We have over 850 individual sharks in our photo library, with 35 sharks that have been photographed on more than one date. The North Carolina Aquariums have made progress towards understanding sand tiger shark habitat use in the northwestern Atlantic. Importantly, pregnant sand tiger sharks are found here during summer, fall and winter, suggesting a key role of this habitat in their reproductive ecology. It is known that many of the shipwrecks in the ‘Graveyard of the Atlantic’ are known aggregation spots for sand tiger sharks, but the extent to which the species relies on this habitat is uncertain. Waters off the North Carolina coast are important for sand tiger sharks year-round. In the US, recreational and commercial fishing are prohibited, and this species is ranked as highly vulnerable to climate change impacts and habitat disruption. They are listed as vulnerable on the IUCN Red List of Threatened Species, and as a species of concern by the National Marine Fisheries Service. Globally, sand tiger shark populations have experienced significant declines. Popular in aquariums because of their fierce appearance but relatively docile nature, sand tiger sharks are valuable ambassadors to spread awareness for threats to sharks and rays. My team of aquarium scientists and students then uses Wildbook® software to map the unique spot patterns visible along the sides of the photographed sharks to identify individual animals. SCUBA divers are asked to photograph the sand tiger sharks they encounter on their adventures and post their images to the Spot A Shark USA website. I am the project manager for Spot A Shark USA – a citizen scientist program that aims to better understand sand tiger shark Carcharias taurus populations along the Atlantic coast.
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