10.5061/DRYAD.NZS7H44SF
Hrenchuk, Lee
0000-0002-6194-094X
IISD Experimental Lakes Area
Blanchfield, Paul
0000-0003-0886-5642
Fisheries and Oceans Canada
Rudd, John
Fisheries and Oceans Canada
Amyot, Marc
Université de Montréal
Babiarz, Christopher
University of Wisconsin-Madison
Beaty, Ken
Fisheries and Oceans Canada
Bodaly, Drew
Fisheries and Oceans Canada
Branfireun, Brian
Western University
Gilmour, Cynthia
Smithsonian Environmental Research Center
Graydon, Jennifer
University of Alberta
Hall, Britt
University of Regina
Harris, Reed
Reed Harris Environmental Ltd.
Heyes, Andrew
University of Maryland, Baltimore
Hintelmann, Holger
Trent University
Hurley, James
University of Wisconsin-Madison
Kelly, Carol
Fisheries and Oceans Canada
Krabbenhoft, David
United States Geological Survey
Lindberg, Steve
Oak Ridge National Laboratory
Mason, Robert
University of Connecticut
Paterson, Michael
IISD Experimental Lakes Area
Podemski, Cheryl
Fisheries and Oceans Canada
Sandilands, Ken
IISD Experimental Lakes Area
Southworth, George
Oak Ridge National Laboratory
St. Louis, Vincent
University of Alberta
Tate, Lori
Fisheries and Oceans Canada
Tate, Michael
United States Geological Survey
Experimental evidence for the recovery of mercury-contaminated fish populations
Dryad
dataset
2021
FOS: Earth and related environmental sciences
Mercury
methylmercury
stable isotopes of mercury
Freshwater fish
whole ecosystem experiment
IISD Experimental Lakes Area*
2021-12-20T00:00:00Z
2021-12-20T00:00:00Z
en
https://doi.org/10.1038/s41586-021-04222-7
15832 bytes
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CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Anthropogenic releases of mercury (Hg) are a human health issue because
the potent toxicant methylmercury (MeHg), formed primarily by microbial
methylation of inorganic Hg in aquatic ecosystems, bioaccumulates to high
concentrations in fish consumed by humans. Predicting the efficacy of Hg
pollution controls on fish MeHg concentrations is complex because many
factors influence the production and bioaccumulation of MeHg. Here we
conducted a 15-year whole-ecosystem, single-factor experiment to determine
the magnitude and timing of reductions in fish MeHg concentrations
following reductions in Hg additions to a boreal lake and its watershed.
During the seven-year addition phase, we applied enriched Hg isotopes to
increase local Hg wet deposition rates fivefold. The Hg isotopes became
increasingly incorporated into the food web as MeHg, predominantly from
additions to the lake because most of those added to the watershed
remained there. Thereafter, isotopic additions were stopped, resulting in
an approximately 100% reduction in Hg loading to the lake. The
concentration of labelled MeHg quickly decreased by more than 85% in lower
trophic level organisms, initiating rapid decreases of 38–76% of MeHg
concentration in large-bodied fish populations in eight years. Although Hg
loading from watersheds may not decline in step with lowering deposition
rates, this experiment clearly demonstrates that any reduction in Hg
loadings to lakes, whether from direct deposition or runoff, will have
immediate benefits to fish consumers.
See manuscript