This study employs a multidisciplinary methodology across natural and social sciences to examine relationships between biodiversity loss at sea and urban consumption with a focus on sea cucumber and dried seafood markets in New York City (NYC). The study identified 34 dried seafood retailers across three NYC Chinatown boroughs: Manhattan, Brooklyn, and Queens. Samples of sea cucumber were collected with Chinese-language labels indicating the commodity was from South America, a region of conservation concern. Comparison samples were taken from sea cucumbers labeled from Mexico and Japan. A mitochondrial DNA barcoding method was used to examine the taxonomic origin of 103 samples. Sequence data were successfully obtained from 74 of the samples, 8 of which were classified as brown sea cucumber (Isostichopus fuscus), an endangered species for which harvest is banned in several locations. Semi-structured interviews with dried seafood retailers and consumers (n = 64), moreover, revealed associations between consuming sea cucumber and enhancing human health and limited knowledge of product origins. Collectively, the findings reveal socio-ecological dynamics wherein endangered species on the market coupled with geographic market labeling practices and varying degrees of retailer and consumer knowledge negatively bear on marine biodiversity. Furthermore, given that brown sea cucumbers are abundant on the market, there is a need for developing genetic markers that can trace geographic origin to determine if species were legally harvested. These results indicate that more robust market labeling, training, genetic research, and public outreach are required to advance One Health in urban seafood markets.