Study finds critically endangered sharks being sold as food in U.S. grocery stores

A new study from the University of North Carolina at Chapel Hill has uncovered that shark meat sold in U.S. grocery stores, seafood markets, and online vendors often comes from endangered species and is frequently mislabeled. Researchers purchased and DNA barcoded 29 shark meat products to determine their species identity, finding that 93% of samples were ambiguously labeled and included meat from 11 different shark species. 

Among the species identified were the great hammerhead and scalloped hammerhead, both listed as critically endangered by the International Union for Conservation of Nature (IUCN). Despite global declines in shark populations, their meat was being sold to American consumers, sometimes for as little as $2.99 per pound. 

“Mislabeling and ambiguous labeling remove consumers’ ability to choose what they are putting in their bodies,” said Savannah Ryburn, Ph.D., first author of the study and co-instructor of the seafood forensics class that conducted the research. “For example, two species in our study, scalloped hammerhead and great hammerhead, were ambiguously labeled as ‘shark,’ even though they are strongly advised against consumption due to their very high mercury levels. Without accurate and precise labeling, consumers cannot avoid purchasing these products.” 

The researchers found that of the 29 products tested, 27 were labeled simply as “shark” or “mako shark” without a species designation. Even among the two products that were labeled with a species name, one turned out to be incorrect. These findings highlight a major gap in seafood transparency and consumer safety. 

“The United States should require seafood distributors to provide species-specific names for the products being sold,” said John Bruno, Ph.D., distinguished professor and co-instructor of the seafood forensics class. 

Shark meat is known to contain high levels of mercury, which can pose serious risks to human health, particularly for children and pregnant people. The researchers emphasize that accurate labeling is essential not only for conservation but also for consumer protection. 

“Sharks such as great and scalloped hammerheads are the ocean’s equivalent of lions, and we were shocked by how cheaply the meat of these rare, long-lived apex predators was sold,” added Ryburn. “Some samples were only $2.99 per pound.” 

The study, which contributes to a limited but growing body of research using DNA barcoding to investigate the accuracy of shark product labeling in the U.S., calls for stronger regulations and oversight of seafood labeling practices. 

The study is available online in the journal Frontiers in Marine Science at: https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2025.1604454/abstract#supplementary-material 

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