title: MERGANSER: an empirical model to predict fish and loon mercury in New England lakes.
abstract: MERGANSER (MERcury Geo-spatial AssessmeNtS for the New England Region) is an empirical least-squares multiple regression model using mercury (Hg) deposition and readily obtainable lake and watershed features to predict fish (fillet) and common loon (blood) Hg in New England lakes. We modeled lakes larger than 8 ha (4404 lakes), using 3470 fish (12 species) and 253 loon Hg concentrations from 420 lakes. MERGANSER predictor variables included Hg deposition, watershed alkalinity, percent wetlands, percent forest canopy, percent agriculture, drainage area, population density, mean annual air temperature, and watershed slope. The model returns fish or loon Hg for user-entered species and fish length. MERGANSER explained 63% of the variance in fish and loon Hg concentrations. MERGANSER predicted that 32-cm smallmouth bass had a median Hg concentration of 0.53 μg g(-1) (root-mean-square error 0.27 μg g(-1)) and exceeded EPA's recommended fish Hg criterion of 0.3 μg g(-1) in 90% of New England lakes. Common loon had a median Hg concentration of 1.07 μg g(-1) and was in the moderate or higher risk category of >1 μg g(-1) Hg in 58% of New England lakes. MERGANSER can be applied to target fish advisories to specific unmonitored lakes, and for scenario evaluation, such as the effect of changes in Hg deposition, land use, or warmer climate on fish and loon mercury.
authors.affiliation: US Geological Survey, P.O. Box 628, Montpelier, Vermont 05601, United States. jshanley@usgs.gov
authors.forename: James B
authors.initials: JB
authors.lastname: Shanley
authors.forename: Richard
authors.initials: R
authors.lastname: Moore
authors.forename: Richard A
authors.initials: RA
authors.lastname: Smith
authors.forename: Eric K
authors.initials: EK
authors.lastname: Miller
authors.forename: Alison
authors.initials: A
authors.lastname: Simcox
authors.forename: Neil
authors.initials: N
authors.lastname: Kamman
authors.forename: Diane
authors.initials: D
authors.lastname: Nacci
authors.forename: Keith
authors.initials: K
authors.lastname: Robinson
authors.forename: John M
authors.initials: JM
authors.lastname: Johnston
authors.forename: Melissa M
authors.initials: MM
authors.lastname: Hughes
authors.forename: Craig
authors.initials: C
authors.lastname: Johnston
authors.forename: David
authors.initials: D
authors.lastname: Evers
authors.forename: Kate
authors.initials: K
authors.lastname: Williams
authors.forename: John
authors.initials: J
authors.lastname: Graham
authors.forename: Susannah
authors.initials: S
authors.lastname: King
mesh_terms: D000818:Animals; D001717:Birds; D004784:Environmental Monitoring; D005399:Fishes; D060106:Lakes; D008628:Mercury / Q000032:analysis*; D008962:Models, Theoretical; D009511:New England; D015203:Reproducibility of Results; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D008628:Mercury