The extent of substitution in seafood commerce in Peru

Seafood substitution, involving mislabeling or fraud, remains a significant issue with ecological, economic, and public health implications. This study investigated the extent, seasonality, and patterns of seafood substitution in three Peruvian coastal cities—Lima, Chiclayo, and Piura—over 12 months. A total of 1189 samples were collected from 76 retail points, including restaurants, supermarkets, and municipal markets. DNA barcode sequencing was used for species identification, revealing a 67.5 % substitution rate. Restaurants exhibited the highest substitution rate (73.8 %), followed by municipal markets (71.1 %) and supermarkets (27.9 %). Fraud was identified in 89.7 % of substitution cases, often involving high-demand or threatened species, such as hammerhead sharks Sphyrna zygaena and Atlantic eel Anguilla anguilla. Seasonal patterns were observed, with certain species like dolphinfish Coryphaena hippurus and searobin Prionotus stephanophrys used more frequently. These findings underscore the need for improved seafood monitoring and enforcement of labeling standards to safeguard marine biodiversity, consumer rights, and economic activities.