title: Trophic influences on mercury accumulation in top pelagic predators from offshore New England waters of the northwest Atlantic Ocean.
abstract: Trophic pathways and size-based bioaccumulation rates of total mercury were evaluated among recreationally caught albacore tuna (Thunnus alalunga), yellowfin tuna (Thunnus albacares), shortfin mako shark (Isurus oxyrinchus), thresher shark (Alopias vulpinus), and dolphinfish (Coryphaena hippurus) from offshore southern New England waters of the northwest Atlantic Ocean between 2008 and 2011. Mercury concentrations were highest in mako (2.65 ± 1.16 ppm) and thresher sharks (0.87 ± 0.71 ppm), and significantly lower in teleosts (albacore, 0.45 ± 0.14 ppm; yellowfin, 0.32 ± 0.09 ppm; dolphinfish, 0.20 ± 0.17 ppm). The relationship between body size and mercury concentration was positive and linear for tunas, and positive and exponential for sharks and dolphinfish. Mercury increased exponentially with δ (15)N values, a proxy for trophic position, across all species. Results demonstrate mercury levels are positively related to size, diet and trophic position in sharks, tunas, and dolphinfish, and the majority of fishes exhibited concentrations greater than the US EPA recommended limit.
authors.affiliation: University of Massachusetts, Department of Environmental Conservation, 160 Holdsworth Way, Amherst, MA 01003-9285, USA. Electronic address: ateffer@uvic.ca.
authors.forename: Amy K
authors.initials: AK
authors.lastname: Teffer
authors.affiliation: University of Massachusetts, Department of Environmental Conservation, 160 Holdsworth Way, Amherst, MA 01003-9285, USA; University of North Carolina Wilmington, Department of Biology and Marine Biology, Wilmington, NC 28403, USA. Electronic address: mstaudinger@usgs.gov.
authors.forename: Michelle D
authors.initials: MD
authors.lastname: Staudinger
authors.affiliation: Roger Williams University, Department of Marine Biology, One Old Ferry Road, Bristol, RI 02809, USA. Electronic address: dtaylor@rwu.edu.
authors.forename: David L
authors.initials: DL
authors.lastname: Taylor
authors.affiliation: University of Massachusetts, Department of Environmental Conservation, 160 Holdsworth Way, Amherst, MA 01003-9285, USA. Electronic address: juanes@uvic.ca.
authors.forename: Francis
authors.initials: F
authors.lastname: Juanes
mesh_terms: D000818:Animals; D001267:Atlantic Ocean; D049628:Body Size; D020387:Food Chain; D008628:Mercury / Q000378:metabolism*; D011235:Predatory Behavior; D012754:Sharks / Q000378:metabolism*; D014413:Tuna / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D014874:Water Pollutants, Chemical; D008628:Mercury
keywords: Bioaccumulation; Dolphinfish; Northwest Atlantic ocean; Sharks; Stable isotopes; Total mercury; Trophic transfer; Tunas