Factors regulating the bioavailability of methylmercury to breeding rusty blackbirds in northeastern wetlands.

Authors:
Samuel Trower Edmonds
Samuel Trower Edmonds
Acadia University
Canada
David C Evers
David C Evers
BioDiversity Research Institute
United States

Environ Pollut 2012 Dec 21;171:148-54. Epub 2012 Aug 21.

K.C. Irving Environmental Science Centre, Department of Earth and Environmental Sciences, Acadia University, Wolfville, NS B4P 2R6, Canada.

Rusty blackbirds are undergoing rapid population decline and have elevated Hg concentrations while breeding in the Acadian ecoregion of North America. Factors regulating the bioavailability of methyl-Hg (MeHg) within this population's habitat were determined using water, invertebrates, and blood from adult rusty blackbirds collected for Hg-speciation, along with additional water column parameters: MeHg and THg, dissolved organic carbon, pH, dissolved oxygen, conductivity, redox potential, and temperature. Both DO(2) and pH were negatively related to biota MeHg, while water MeHg concentrations were positively related. Both invertebrate MeHg concentration and %MeHg increased with trophic level. Invertebrate MeHg concentrations were among the greatest reported when compared with those reported elsewhere for wetlands and waterbodies-often several times greater for similar taxa-while percent MeHg of THg were similar. An environment with high bioavailability of MeHg in combination with a high trophic position best explains elevated Hg concentrations for this species regional population.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envpol.2012.07.044DOI Listing
December 2012
68 Reads

Publication Analysis

Top Keywords

rusty blackbirds
12
elevated concentrations
8
mehg concentrations
8
invertebrate mehg
8
mehg
8
mehg thg
8
regulating bioavailability
8
factors regulating
8
biota mehg
4
negatively biota
4
do2 negatively
4
mehg water
4
concentration %mehg
4
positively invertebrate
4
temperature do2
4
concentrations positively
4
mehg concentration
4
water mehg
4
conductivity redox
4
column parameters
4

Similar Publications

Concentrations of methylmercury in invertebrates from wetlands of the Prairie Pothole Region of North America.

Environ Pollut 2012 Jan 15;160(1):153-60. Epub 2011 Oct 15.

Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada.

Prairie wetlands may be important sites of mercury (Hg) methylation resulting in elevated methylmercury (MeHg) concentrations in water, sediments and biota. Invertebrates are an important food resource and may act as an indicator of MeHg exposure to higher organisms. In 2007-2008, invertebrates were collected from wetland ponds in central Saskatchewan, categorized into functional feeding groups (FFGs) and analyzed for total Hg (THg) and MeHg. Read More

View Article
January 2012

Invertebrate mercury bioaccumulation in permanent, seasonal, and flooded rice wetlands within California's Central Valley.

Sci Total Environ 2010 Jan 31;408(3):666-71. Epub 2009 Oct 31.

U. S. Geological Survey, Western Ecological Research Center, Davis Field Station, One Shields Avenue, University of California, Davis, CA 95616, USA.

We examined methylmercury (MeHg) bioavailability in four of the most predominant wetland habitats in California's Central Valley agricultural region during the spring and summer: white rice, wild rice, permanent wetlands, and shallowly-flooded fallow fields. We sampled MeHg and total mercury (THg) concentrations in two aquatic macroinvertebrate taxa at the inlets, centers, and outlets of four replicated wetland habitats (8 wetlands total) during two time periods bounding the rice growing season and corresponding to flood-up and pre-harvest (96 total samples). In general, THg concentrations (mean+/-standard error) in Notonectidae (Notonecta, back swimmers; 1. Read More

View Article
January 2010

Methylmercury levels and bioaccumulation in the aquatic food web of a highly mercury-contaminated reservoir.

Environ Int 2011 Oct 11;37(7):1213-8. Epub 2011 Jun 11.

Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research, IDAEA-CSIC, Jordi Girona, 18-26. E-08034 Barcelona, Spain.

The low Ebro River basin (NE Spain) represents a particular case of chronic and long-term mercury pollution due to the presence of an industrial waste (up to 436 μg/g of Hg) coming from a chlor-alkali plant Albeit high total mercury (THg) levels have been previously described in several aquatic species from the surveyed area, methylmercury (MeHg) values in fish individuals have never been reported. Accordingly, in order to investigate bioaccumulation patterns at different levels of the aquatic food web of such polluted area, crayfish and various fish species, were analysed for THg and MeHg content. At the hot spot, THg mean values of crayfish muscle tissue and hepatopancreas were 10 and 15 times, respectively, greater than the local background level. Read More

View Article
October 2011

Methylmercury in water, sediment, and invertebrates in created wetlands of Rouge Park, Toronto, Canada.

Environ Pollut 2012 Dec 30;171:207-15. Epub 2012 Aug 30.

Department of Physical and Environmental Science, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON, Canada M1C 1A4.

Thousands of hectares of wetlands are created annually because wetlands provide beneficial ecosystem services. Wetlands are also key sites for production of the bioaccumulative neurotoxin methylmercury (MeHg), but little is known about MeHg production in created systems. Here, we studied methylmercury in sediment, water, and invertebrates in created wetlands of various ages. Read More

View Article
December 2012