Presentation Abstract
Mercury (Hg) levels and trends in the NE Pacific Ocean are due to the convergence between natural and anthropogenic sources, with the latter broadly related to a combination of local and long-range sources. Legacy and current local point sources include chlor-alkali plants, pulp and paper mills and other mixed sources. In addition, long-range atmospheric and oceanic pathways deliver mercury to the Pacific coast, primarily from points to the west, where it is taken up by algae and bacteria and transferred through the marine food web in its inorganic form, but also its organic form, methylmercury. We present data on Hg trends in pelagic cormorant ((Phalacrocorax pelagicus) and great blue heron (Ardea herodias) eggs in Pacific Canada over a 48 year period. Temporal trends are evaluated using both diet- and non-diet-adjusted data and compared to Hg trends observed in other seabird species in the region, as well as the Atlantic and Arctic Oceans. Mercury concentrations declined alongside δ34S over time in both species, but no trend for δ13C and δ15N was apparent. The present study provides explanations for these trends in the context of local and long-range sources in the region and dietary contributions.
Session Title
Contaminants in the Salish Sea: Effects of Aquaculture Pharmaceuticals on Invertebrates and Contaminants in Aquatic Birds and Mammals
Keywords
Mercury, Seabirds
Conference Track
SSE3: Fate, Transport, and Toxicity of Chemicals
Conference Name
Salish Sea Ecosystem Conference (2018 : Seattle, Wash.)
Document Type
Event
SSEC Identifier
SSE3-636
Start Date
5-4-2018 2:00 PM
End Date
5-4-2018 2:15 PM
Type of Presentation
Oral
Genre/Form
conference proceedings; presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Mercury--Environmental aspects--Salish Sea (B.C. and Wash.); Mercury--Toxicology--Salish Sea (B.C. and Wash.); Pollutants--Salish Sea (B.C. and Wash.); Cormorants--Eggs--Salish Sea (B.C. and Wash.); Great blue heron--Eggs--Salish Sea (B.C. and Wash.)
Geographic Coverage
Salish Sea (B.C. and Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Included in
Fresh Water Studies Commons, Marine Biology Commons, Natural Resources and Conservation Commons, Terrestrial and Aquatic Ecology Commons
Mercury trends in cormorant and great blue heron eggs from Pacific Canada: a question of local and global sources
Mercury (Hg) levels and trends in the NE Pacific Ocean are due to the convergence between natural and anthropogenic sources, with the latter broadly related to a combination of local and long-range sources. Legacy and current local point sources include chlor-alkali plants, pulp and paper mills and other mixed sources. In addition, long-range atmospheric and oceanic pathways deliver mercury to the Pacific coast, primarily from points to the west, where it is taken up by algae and bacteria and transferred through the marine food web in its inorganic form, but also its organic form, methylmercury. We present data on Hg trends in pelagic cormorant ((Phalacrocorax pelagicus) and great blue heron (Ardea herodias) eggs in Pacific Canada over a 48 year period. Temporal trends are evaluated using both diet- and non-diet-adjusted data and compared to Hg trends observed in other seabird species in the region, as well as the Atlantic and Arctic Oceans. Mercury concentrations declined alongside δ34S over time in both species, but no trend for δ13C and δ15N was apparent. The present study provides explanations for these trends in the context of local and long-range sources in the region and dietary contributions.
