Regional variation in mercury bioaccumulation among NW Atlantic Golden (Lopholatilus chamaeleonticeps) and Blueline (Caulolatilus microps) Tilefish. (1st September 2021)

• Record Type: Journal Article
• Authors: Roose, Hunter; Paterson, Gordon; Frisk, Michael G.; Cerrato, Robert M.; Nitschke, Paul; Olin, Jill A.
• Is Part Of: Environmental pollution. Volume 284(2021)
• Publication Date: 2021-09-01
• Subjects: Body size -- Continental shelf -- Malacathidae -- Resource partitioning -- Sex -- Nitrogen stable isotopes; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2021.117177
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Mercury (Hg) concentrations in fishes from the NW Atlantic Ocean pose concern due to the importance of this region to U.S. fisheries harvest. In this study, total Hg (THg) concentrations and nitrogen stable isotope (δ 15 N) values were quantified in muscle tissues sampled from Golden ( Lopholatilus chamaeleonticeps) and Blueline ( Caulolatilus microps ) Tilefish collected during a fishery-independent survey conducted in the NW Atlantic to compare bioaccumulation patterns between these species. Total Hg concentrations averaged (±SD) 0.4 ± 0.4 μg/g dry weight (d.w.) for L . chamaeleonticeps and 1.1 ± 0.7 μg/g d.w. for C . microps with <2% of all sampled fish, those >70 cm fork length, exceeding the most restrictive USEPA regulatory guidelines for human consumption (THg > 0.46 μg/g w.w.), when converted to wet weight concentrations. The THg concentrations reported here for individuals from the NW Atlantic stock are comparable to those reported for similarly sized individuals collected from the SW Atlantic stock but notably lower than those reported for Gulf of Mexico L. chamaeleonticeps, indicating different Hg exposure and assimilation kinetics for fish from the NW Atlantic, and highlights the broad geographic variability of Hg bioaccumulation among Tilefish stocks. Caulolatilus microps had higher δ 15 N values relative to L . chamaeleonticeps and a pattern of decreasing THg concentrations was also present from south to north across the study range. It is concluded that this trophic difference and spatial pattern in Tilefish THg concentrations emphasizes the habitat and resource partitioning mechanisms described for these sympatric species that permits their coexistence in the continental shelf environment. Importantly, regional variability in THg concentrations accentuate the possible roles of fine-scale biotic and abiotic processes that can act to regulate Hg bioaccumulation among individuals and species. Graphical abstract: Caption: Regional THg (μg/g d.w.) content in muscle tissue of two Tilefish species from the NW Atlantic (images: https://www.fishwatch.gov/profiles/Tilefish ). Colored circles represent catch with larger circles indicating greater catch. Image 1 Highlights: Total mercury (THg) concentrations were examined in Tilefishes in the NW Atlantic. Intra- and inter-specific THg bioaccumulation patterns relate to body size and region. THg concentrations were low with <2% fish exceeding restrictive USEPA guidelines. THg in NW Atlantic fish was lower than reported for Gulf of Mexico conspecifics. Findings inform guidance toward regional THg contamination of high-value fisheries.