Sharks have gracefully traversed the oceans for over 450 million years, surviving cataclysmic shifts in Earth’s climate and ecosystems. Yet in recent decades, their ancient lineage faces unprecedented peril. Since the 1970s, global shark populations have precipitously declined by over 70%, largely propelled by intensive human activities such as shark finning, bycatch, and unsustainable fishing practices. Compounding these pressures are habitat degradation, pollution, and the far-reaching impacts of climate change, all converging to threaten shark species worldwide. The International Union for the Conservation of Nature (IUCN) currently classifies a staggering percentage of shark species as at risk: roughly 14% vulnerable, 11% endangered, and an alarming 12% critically endangered within the approximately 550 known shark species.
In response to this crisis, international regulatory frameworks like the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) have sought to protect these imperiled creatures by banning or severely restricting trade in their meat and byproducts. Despite these legal safeguards, emerging research exposes a disheartening reality: the illegal sale of meat from endangered sharks persists, often under misleading or generic labels, circumventing regulations intended to halt their exploitation. This unsettling revelation comes from a recent study published in the journal Frontiers in Marine Science, which performed a systematic investigation into the presence of critically endangered sharks in U.S. marketplaces.
The study, spearheaded by Dr. Savannah J. Ryburn of the University of North Carolina at Chapel Hill, deployed DNA barcoding techniques to accurately identify shark meat products purchased in grocery stores, seafood markets, and online vendors in several U.S. states including Washington DC, North Carolina, Florida, and Georgia. DNA barcoding is a molecular method that examines specific gene sequences — often a fragment of the mitochondrial cytochrome c oxidase I (COI) gene — unique to each species, enabling precise identification even when the physical characteristics of the shark meat are no longer discernible. This approach is vital because shark meat in commercial products is frequently processed into fillets or jerky where all morphological identifiers are removed, masking the true species origin.
A total of 30 shark products were purchased by the study’s research team over 2021 and 2022, comprising 19 raw shark steaks and 11 packages of shark jerky. Of these, 29 samples were successfully identified to the species level, revealing a disturbing pattern: 31% of the products originated from species classified as endangered or critically endangered, specifically great hammerhead, scalloped hammerhead, tope, and shortfin mako sharks. The prevalence of these imperiled species in the commercial supply chain starkly contradicts the intended effect of conservation laws and exposes consumers to unwittingly supporting illegal wildlife trade.
Compounding the deceptive labeling practices, the study found that 93% of the samples were ambiguously labeled simply as “shark,” a vague descriptor that conceals the species-specific provenance of the meat. Additionally, among the two products labeled with a species name, one was found to be blatantly mislabeled: a product marked as blacktip shark (a species vulnerable but less endangered) was genetically identified as shortfin mako, which is endangered. This widespread mislabeling not only undermines enforcement efforts but also jeopardizes consumer choices and awareness regarding threatened species conservation.
From an economic perspective, these shark products were surprisingly affordable, priced between $6.56 and $11.99 per kilogram for fresh shark meat, with shark jerky commanding an average price of $207.37 per kilogram. This low cost suggests the existence of a lucrative but illicit market where endangered shark species are commodified and distributed widely without scrutiny. It further highlights the urgent need for stricter monitoring and regulatory oversight throughout the entire value chain from catch to consumer.
The study also raises critical human health concerns beyond conservation implications. Certain sharks identified in the sample set — including scalloped hammerhead, great hammerhead, and dusky smooth-hound sharks — accumulate and retain hazardous heavy metals such as mercury, methylmercury, and arsenic. These toxic substances are well-documented neurotoxins that impair brain function and damage the central nervous system, posing severe health risks especially to vulnerable groups like pregnant women and developing fetuses. Chronic exposure to arsenic and methylmercury is linked to cancer and developmental abnormalities, adding a grave dimension to the consumption risks associated with shark meat.
The regulatory landscape governing shark fisheries and trade in the United States is complex, relying heavily on geographic and species-specific provisions under CITES and the Endangered Species Act. However, regulatory efficacy is hampered by the inherent difficulty in species-level identification once shark meat is processed, as well as by insufficient labeling requirements. Dr. Ryburn emphasizes that by the time these sharks arrive at retail outlets, distinguishing features are stripped away, making even sellers unlikely to possess accurate knowledge about the species they are vending. This opacity in the supply chain creates a loophole that facilitates the persistence of illegal trade and complicates conservation enforcement.
Given these findings, the authors advocate for sweeping reforms in labeling transparency and traceability protocols. They recommend mandatory species-specific identification on all shark meat products to enable consumers to make informed choices and facilitate enforcement authorities in tracking illegal trade. From a consumer ethics perspective, avoiding shark meat purchases lacking clear species labeling or traceability supports both biodiversity preservation and public health safeguards. Where shark meat is not a food security necessity, restraint in consumption can significantly reduce market demand driving the exploitation of threatened species.
The broader implications of this research impel a reevaluation of seafood regulatory frameworks and consumer awareness campaigns worldwide. Bridging the gap between conservation policy and marketplace realities requires integrating scientific techniques such as DNA barcoding into routine seafood monitoring programs. It also demands collaborative efforts among governments, industry stakeholders, scientists, and consumers to promote sustainable seafood procurement, combat wildlife trafficking, and foster biodiversity resilience in marine ecosystems.
As shark populations continue to dwindle due to overexploitation and environmental change, robust science-driven interventions are indispensable to conserve these apex predators that play a pivotal role in marine health. This study underscores the urgency of addressing gaps in enforcement and consumer transparency to curb the clandestine sale of endangered shark species. In doing so, it enhances our understanding of the complex interfaces between conservation, commerce, and public health, urging a paradigm shift towards more accountable and sustainable seafood supply chains.
The fight to save sharks is far from over; it is a multifaceted challenge that demands vigilance, innovation, and collective responsibility. As this research reveals, every shark fillet or piece of jerky on the shelf may carry the weight of extinction — a sobering reminder that safeguarding marine biodiversity requires the persistent scrutiny of even the most innocuous culinary choices.
Subject of Research: Animals
Article Title: Sale of critically endangered sharks in the United States
News Publication Date: 10-Sep-2025
Web References:
Frontiers in Marine Science article
DOI: 10.3389/fmars.2025.1604454
Keywords: Sharks, Endangered species, DNA barcoding, Shark conservation, Seafood labeling, Illegal wildlife trade, Heavy metal contamination, Marine biodiversity, Species mislabeling, CITES regulations, Consumer health risks, Seafood forensics
