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bioRxiv · 10.1101/2023.07.30.551124

Sale of critically endangered sharks in the United States

Abstract

Shark meat is widely available in the United States in grocery stores and seafood markets. The meat is often mislabeled or generically labeled as "shark". The ambiguity of these generic labels makes it challenging to assess the conservation implications of this practice and for consumers to avoid species with high mercury concentrations. For this study we purchased and DNA barcoded 30 shark products purchased in the United States to determine their species identity and conservation status. These samples consisted of 19 filets sold in grocery stores, seafood markets, and Asian specialty markets (mostly in North Carolina) and 11 ordered online as "jerky". 70% of samples were "soft mislabeled" (i.e., labeled generically as shark but not as a specific species). Of the nine samples labeled to species, eight were mislabeled (e.g., spinner shark labeled as mako shark). Only one sample was correctly labeled. All 30 samples were identified as shark and came from 11 different species, including three species listed by the IUCN as Critically Endangered: great hammerhead, scalloped hammerhead, and tope. The first two species have been found to contain very high levels of mercury, illustrating the implications of seafood mislabeling for human health. The widespread availability of shark meat in U.S. grocery stores is surprising given the dramatic decline of shark populations globally. Moreover, the fact that nearly all shark meat is either mislabeled or not labeled to species amplifies the problem. Accurate, verified product labels for shark meat would benefit consumers and shark conservation efforts, and should be a priority for the seafood industry.

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BibTeXRIS

Ryburn, S. J., Yu, T., Ong, K. J.-W., Alston, M. A., Howie, E., LeRoy, P., Giang, S. E., Ball, W., Benton, J., Calhoun, R., Favreau, I., Gutierrez, A., Hallac, K., Hanson, D., Hibbard, T., Loflin, B., Lopez, J., Mock, G., Myers, K., Pinos-Sanchez, A., Suarez Garcia, A. M., Romero, A. R., Thomas, A., Williams, R., Zaldivar, A., Bruno, J. F.. 2023-08-02. Sale of critically endangered sharks in the United States. https://doi.org/10.1101/2023.07.30.551124

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