July 16-21 — Providence, Rhode Island
The International Conference on Mercury as a Global Pollutant (ICMGP) is committed to better understanding and effectively managing mercury releases and emissions to decrease human and wildlife exposure. This biennial conference brings together a diversity of participants in terms of country of origin, gender, discipline, sector, and perspective. The theme of this year's conference is Integrating Mercury Research and Policy in a Changing World.
The BRI booth offers participants and members of the media
a place to meet our researchers to discuss current projects,
and an opportunity to browse our library of science communications
ICMGP 2017 will be held in Providence, Rhode Island, July 16-21.
Amy Sauer, Ph.D. Candidate – Songbird Program Director
Monitoring Spatial Gradients and Temporal Trends of Mercury in Songbirds of New York State
Monday, July 17 — 10:30-10:45 a.m.
Abstract: Mercury (Hg) contamination in aquatic and terrestrial ecosystems is a widespread issue that poses considerable reproductive, behavioral and physiological risks to wildlife populations. Songbirds are now recognized as indicators of mercury in terrestrial ecosystems, where invertivore foodwebs biomagnify methylmercury (MeHg) to levels that can adversely affect reproductive success. With upcoming changes to Hg emissions regulations, understanding how MeHg bioavailability currently varies across the landscape is important for quantifying the effects of these changes. Building upon 13 years of mercury research in New York State, a five-year project was initiated in 2013, to identify at-risk songbird species, classify sensitive habitat types, and to assess spatial and temporal trends of mercury across a variety of ecosystems. To date, approximately 1,900 blood and feather samples have been collected and analyzed from songbirds across the state. This project focuses on: (1) annual sampling and monitoring at established study sites to evaluate temporal patterns in songbird mercury exposure; (2) sampling selected sites statewide to identify mercury hotspots for inclusion into a predictive map documenting spatial gradients of methylmercury availability; and (3) analysis of museum specimens to quantify trends in Hg exposure over the 20th Century.
Chris DeSorbo, M.S. – Raptor Program Director; BRI Deputy Director
Mercury exposure and impacts in Bald Eagles in the Penobscot River Watershed, Maine
Monday, July 17 — 11:15-11:30 a.m.
Abstract: We evaluated dietary Hg exposure in Bald Eagle (Haliaeetus leucocephalus) nestlings throughout Maine’s Penobscot River watershed in 2004 – 2015, focusing particularly on exposure relative to the location of a significant Hg point source (HoltraChem) located in a brackish portion of the Penobscot River. The Penobscot River watershed encompasses more than one-quarter of the state, stretching over 150 km from northern lakes to an estuary and Penobscot Bay. Geometric mean Hg concentrations in nestling blood (range 0.06 – 1.51 µg/g) and feathers (range 2.9 – 46.8 µg/g) varied significantly across the four major habitat types in the study area (p < 0.05). Means generally followed the pattern: lakes > freshwater rivers > brackish rivers > marine. The overarching influence of habitat type on Hg exposure in Bald Eagle nestlings masked detection of the possible influence of Hg exposure attributable to HoltraChem. We also compared reproductive measures (productivity, young fledged / occupied nest; nest success, proportion of nests successfully fledging ≥1 young) to eagle tissue Hg concentrations and will discuss those relationships and influential factors. Bald Eagle tissue Hg concentrations found in lakes and freshwater rivers in the Penobscot River watershed are similar or higher than virtually all comparably sampled Bald Eagle populations elsewhere. Eagles at lakes in the Penobscot River Watershed were most similar to a site in BC Canada associated with a Hg mine. In contrast, eagle sampling sites below HoltraChem, one of the most substantial Hg pollution point sources in the country, exhibited relatively low concentrations of Hg due to the predominant influence of factors associated with habitat type. We attribute the notable exposure of Hg in lake- and freshwater river-dwelling Bald Eagles in the Penobscot River watershed upstream from HoltraChem to the combined influences of atmospheric deposition, other point sources, and site-specific biogeochemical factors. Bald Eagles have been repeatedly proven to be valuable contaminant bioindicators at site-specific and watershed scales in both freshwater and marine ecosystems; however, eagles’ large home range and dietary plasticity limits their use in smaller scale, traditional ‘upstream vs. downstream’ contaminant risk evaluations, particularly those spanning multiple habitat types.
David G. Buck, Ph.D. – Director Tropical Program
A meta-analysis of fish mercury concentrations in South America: identifying patterns, trends and hotspots for future biomonitoring related to the Minamata Convention on Mercury
Tuesday, July 18 — 3:00-3:15 p.m.
The Minamata Convention was established to protect humans and the environment from exposure to mercury. Implementation of the Convention will rely on signatory countries adopting a series of measures to limit the amount of Hg used in commercial and industrial practices, reduce emissions and releases of Hg, and establish legislation and trade policies to further reduce and restrict the amount of Hg available on the global market (UNEP 2013). The Convention’s success at achieving its goal of protecting human health and the environment can be assessed using a variety of short-, medium- and long-term metrics that monitor compliance with stipulations set forth in the Convention (Evers et al. 2016). The Convention also recognizes the important role that monitoring environmental Hg concentrations will have in assessing its long-term effectiveness. Articles 19 and 22 of the Convention specifically address the importance of biomonitoring to evaluate spatial and temporal patterns and trends of Hg in the environment at geographically relevant scales. Here we present data on fish mercury concentrations from South America to identify patterns and trends in environmental Hg concentrations at the continental scale. The Web of Science was used to search for published literature using the search terms “mercury AND fish AND [country name]”.
Additional searches were conducted using Google Scholar. All literature published prior to April 2016 were collected for inclusion in the database resulting in more than 200 peer-reviewed sources. At least one peer-reviewed source was identified from each country with the exception of Guyana and Paraguay. To-date, our database includes results from 110 peer-reviewed sources representing 24,550 individual fish tissue samples. Samples reflect environmental Hg concentrations in more than 240 sites within 100 different major waterbodies across the continent. Mercury concentrations ranging from below detection limit to 4.4 parts per million (wet weight) are reported in 403 different species representing 227 different genera. The most commonly sampled taxa include species within the Serrasalmus (piranhas), Hoplias (tigerfishes) Pseudoplatystoma (sorubim catfishes) and Odontesthes (silversides) genera. Subsequent analysis will incorporate spatial data on known point sources of mercury, ecosystem types, geology and hydrology to better understand abiotic variables that influence environmental mercury concentrations. Ultimately, these data provide a baseline for identifying biological mercury hotspots of concern for human and ecological health at the continental scale. This baseline will help prioritize future biomonitoring efforts to best evaluate the long-term effectiveness of policy decisions related to the implementation of the Minamata Convention.
Evan Adams, Ph.D. – Ecological Modeler
Influences of habitat and space on abiotic and biotic mercury levels in Acadia National Park, Maine
Thursday, July 20 — 4:00-4:15 p.m.
Mercury contamination has been documented in Acadia National Park for many decades. The resultant data set of 20 years of studies provides an opportunity to synthesize what we know about mercury in the park. Our objectives were to describe how mercury concentrations vary across space within the park, explain species-level variation in mercury, and quantify how habitat influences the relationship between abiotic and biotic mercury levels. To do this, we created a database of mercury studies in Acadia National Park from published scientific papers, reports, and databases maintained by the park and other organizations. We found sufficient metadata that detailed when and where samples were collected for 675 records of abiotic samples (mercury in surface water) and 1035 records of biotic samples (mercury in blood, feather, egg, muscle, fur, and whole body samples, ranging from invertebrates to eagles). Then we grouped the data by watershed and built two spatially linked statistical models in a Bayesian modeling framework. The first is a model that predicts abiotic mercury using stream- or lakewater pH, dissolved organic carbon (DOC), time of year, watershed, and habitat surrounding the sample site. The second is a model that predicts biotic mercury using the type of sample collected, the species sampled, time of year, watershed, and the surrounding habitat. After fitting the model using Markov chain Monte Carlo sampling, we found that abiotic and biotic mercury were not correlated at the watershed scale. Abiotic mercury levels were strongly correlated with water body chemistry (pH, DOC) and the habitat surrounding each of the samples. Biotic mercury was strongly related to time of year and the type of sample taken, but few species were significantly higher or lower than the mean for all species. Moreover, surrounding habitat did not seem to strongly influence biotic mercury levels. These results suggest that mercury exposure is consistent (and relatively high) across the biota we sampled in the park. The lack of correlation between abiotic and biotic mercury could be due to a lack of connection between some animal mercury exposure and mercury in the surface waters, a mismatch between the spatial scale that the biota represent within their environment, or the scale at which we measured the habitat (e.g., local versus watershed scale). Further, the data document the ubiquity of mercury contamination across the many habitats in Acadia National Park.
David G. Buck, Ph.D. – Director Tropical Program
Biological mercury hotspots in the watersheds of the Mesoamerican Barrier Reef System
Tuesday, July 18 — Poster Session 4:30-5:30 p.m.
The Mesoamerican Barrier Reef System (MBRS) is the largest barrier reef in the Northern Hemisphere, extending over 1000 kilometers from the Yucatan Peninsula of Mexico to the Bay Islands of northern Honduras. It is a UNESCO World Heritage Site, renowned for its marine biodiversity. An estimated 2 million people from Mexico, Belize, Guatemala, and Honduras depend on the reef for their economic livelihoods. A series of stressors are impacting the health of the reef including rapid coastal development, overfishing, and poor agricultural practices within the watersheds that drain into the reef. In addition, recent data suggest that mercury contamination may be impacting both freshwater and marine fishes of the barrier reef ecosystem. Here, we present mercury concentrations from more than 700 individual fishes including both freshwater and marine species. Freshwater fishes were collected in the major watersheds of Belize, Guatemala, and Honduras that drain into the barrier reef. Additional marine species were collected via market landings and direct capture. Results highlight biological mercury hotspots where fish mercury concentrations are elevated above both U.S. EPA and World Health Organization human consumption guidelines. Hotspots include the Chalillo Reservoir and upper Belize River in Belize and Lago Yojoa of northern Honduras. In addition, we identify freshwater and marine species that represent both healthy and risky choices for human fish consumption. Riskier choices include amberjack, mackerel and barracuda with average mercury concentrations above 0.5 parts per million, wet weight (ppm, ww). Healthier choices are fishes with mercury concentrations below 0.3 ppm (ww) and include hogfish, spiny lobster, and several species of snapper. These data provide a potential model for future human health consumption guidelines for freshwater and marine fishes of the MBRS and also the need for more extensive research on potential sources of contaminants in the greater MBRS watershed.
Oksana Lane, M.S. - Director Wetlands Program
Long-term Monitoring of Mercury in Songbirds in the Northeast of the United States
Monday, July 17 — Poster Session 4:30-5:30 p.m.
Mercury (Hg) contamination in aquatic ecosystems is known to pose reproductive and health risks to biota. In past studies, we found high levels of Hg exposure in salt marsh obligate bird species, suggesting that high degrees of bioaccumulation and biomagnification occur in these ecosystems. What is currently unknown are the annual trends and variance seen in biota Hg levels. Invertivorous songbirds, such as Saltmarsh Sparrows are now recognized as best indicators of mercury in the salt marsh ecosystems, where methylmercury (MeHg) biomagnifies in the food chain to levels that can adversely affect reproductive success. With changes to Hg emissions regulations, understanding how MeHg bioavailability changes over time in biota is important. To assess annual mercury changes in mercury exposure of salt marsh songbirds, we non-lethally sampled blood and feathers from several species: Nelson’s Sparrow in Maine, Saltmarsh Sparrow in Maine, Massachusetts and New York, USA and Seaside Sparrow in New York to detect and assess Hg changes over time in the same study areas. We analyzed over 13 years of blood and feather mercury data collected from salt marsh-breeding birds from 2001 to 2016, to quantify magnitude and trends of mercury exposure for these species of conservation concern. We found that Hg concentrations are significantly different by site, species, and individual age and temporal trends vary by location. Many locations show decline in Hg exposure over the study time period while fewer are stable or increasing. As a result of this study; 1) we identified several “hot spots” of mercury in the northeast: (2) we evaluated temporal trends in songbird mercury exposure in northeastern salt marshes of the United States. Keywords: Methylmercury, Northeast USA, Songbirds, Salt marsh, saltmarsh sparrow, Nelson’s sparrow, seaside sparrow Theme/Topic: Sources and cycling of mercury in terrestrial systems; Mercury fate in aquatic and terrestrial food webs
© 2017 Biodiversity Research Institute is a 501(c)3 non-profit