Molecular Identification of Shark Meat From Local Markets in Southern Brazil Based on DNA Barcoding: Evidence for Mislabeling and Trade of Endangered Species

Abstract

Elasmobranchs, the group of cartilaginous fishes that include sharks and rays, are especially vulnerable to overfishing due to low fecundity and late sexual maturation. A significant number of elasmobranch species are currently overexploited or threatened by fisheries activities. Additionally, several recent reports have indicated that there has been a reduction in regional elasmobranch population sizes. Brazil is an important player in elasmobranch fisheries and one of the largest importers of shark meat. However, carcasses entering the shark meat market have usually had their fins and head removed, which poses a challenge to reliable species identification based on the morphology of captured individuals. This is further complicated by the fact that the internal Brazilian market trades several different elasmobranch species under a common popular name: “cação.” The use of such imprecise nomenclature, even among governmental agencies, is problematic for both controlling the negative effects of shark consumption and informing the consumer about the origins of the product. In this study, we used DNA barcoding (mtDNA, COI gene) to identify, at the species level, “cação” samples available in local markets from Southern Brazil. We collected 63 samples traded as “cação,” which we found to correspond to 20 different species. These included two teleost species: Xiphias gladius (n = 1) and Genidens barbus (n = 6), and 18 species from seven elasmobranch orders (Carcharhiniformes, n = 42; Squaliformes, n = 3; Squatiniformes, n = 2; Rhinopristiformes, n = 4; Myliobatiformes, n = 3; Rajiformes, n = 1; and Torpediniformes, n = 1). The most common species in our sample were Prionace glauca (n = 15) and Sphyrna lewini (n = 14), while all other species were represented by four samples or less. Considering IUCN criteria, 47% of the elasmobranch species found are threatened at the global level, while 53% are threatened and 47% are critically endangered in Brazil. These results underline that labeling the meat of any shark species as “cação” is problematic for monitoring catch allocations from the fishing industry and discourages consumer engagement in conservationist practices through informed decision-making.

Sistema Integrado De Manejo De Fauna

“…Elasmobranch commercialization as a fishing resource has always been a common activity for coastal human populations, who make use of elasmobranch meat and some byproducts. This trade has, however, become increasingly and continuously exploited globally, sometimes in an flawed manner, resulting in extinction risks to several species (FAO, 1999;MUSICK 2005b;CERUTTI-PEREYRA et al, 2012;SEMBIRING et al, 2015;FIELDS et al, 2015;STEINKE et al, 2017;GEMAQUE et al, 2017;ALMERÓN-SOUZA et al, 2018;MUTAQIN et al, 2019) Among elasmobranchs, sharks are a particularly important fishing resource, caught by diverse fishing gears in different areas worldwide. Their importance is partly due to the finning trade, which displays high commercial value (CARDEÑOSA et al, 2018).…”

“…In this context, molecular methodologies, such as DNA Barcoding, may be applied to correctly identify different species, as they allow for better accuracy in elasmobranch identification (WARD et al, 2005, HOLMES et al, 2009ASIS et al, 2014;BINEESH et al, 2017;FIELDS et al, 2015;SEMBIRING et al, 2015;VAN DER MERWE & GLEDHILL, 2015;CHUANG et al, 2016;STEINKE et al, 2017;ALMERÓN-SOUZA et al, 2018;FEITOSA et al, 2018;FERRETE et al, 2019;HAQUE et al, 2019;HELLBERG et al, 2019;MUTTAQIN et al, 2019;RODRIGUES-FILHO et al, 2020). Thus, the DNA Barcode technique serves as a basic tool in the implementation of shark and ray management plans aiming at conservation actions.…”

Habitat Use Patterns and Identification of Essential Habitat for an Endangered Coastal Shark With Vertebrae Microchemistry: The Case Study of Carcharhinus porosus

“…Sharks in Brazil are facing similar problems, and legislation aiming at mitigating them has not followed along (Barreto et al, 2017). In addition, several nationally and internationally endangered species are consistently caught as bycatch in the shrimp and teleost targeted fisheries (Palmeira et al, 2013;Almerón-Souza et al, 2018;Feitosa et al, 2018). Brazil's Northern Coast (BNC) is the main region in the country where sharks experience bycatch (Oliver et al, 2015).…”

DNA-based analysis of shark products sold on the Indonesian market towards seafood labelling accuracy program

“…Previously, it has been reported about fish landing monitoring and trade of critically endangered Indonesian sharks and rays (Sembiring et al 2015;Yulianto et al 2018). Sharks and rays belong to Elasmobranch group which known to exhibit low fecundity and late sexual maturation (Bornatowski et al 2014;Almeron-Souza et al 2018). This group of fish has gained worldwide attention concerning conservation and management due to their high vulnerability to extinction.…”

“…This group of fish has gained worldwide attention concerning conservation and management due to their high vulnerability to extinction. The trend of globally trading of their meat reached 42% from 2000 to 2011 (FAO 2015;Almeron-Souza et al 2018). In some regions, sharks remain important protein sources for human foods and some of their body parts have been ingredients for popular dishes (Steinke 2017;Muttaqin et al 2019;Giovos et al 2020).…”