Colonial Waterbird Health and Contaminants, Oil Sands Region
Colonial Waterbird Health and Contaminants
This dataset contains metals, including total mercury levels, stable nitrogen isotope values, polycyclic aromatic hydrocarbons, and polychlorinated dibenzodioxin (PCDDs) and polychlorinated dibenzofuran (PCDFs) levels in eggs of seven species of colonial waterbirds (California Gull, Franklin’s Gull, Herring Gull, Ring-billed Gull, Caspian Tern, Common Tern and Forster's Tern). Data are available for 1977, 2009, and 2011 – 2015 for sites located in the Peace-Athabasca Delta/western Lake Athabasca. Geographic coverage was expanded in 2014 and 2015 to include additional egg collection sites across Alberta, Saskatchewan, and the Northwest Territories.
While no applicable guidelines exist for these measurements, our expert assessment is that the observed levels of mercury are not likely to pose a risk to these bird populations.
In recent collection years – 2008 to 2015 – the data show that while mercury levels in eggs vary from one year to the next they do not reveal a pattern of increase in egg mercury levels over that period. A comparison of recent data on the eggs of California Gulls from Egg Island, Lake Athabasca to eggs collected from the same location in 1977 (the earliest collection) indicated an increase in mercury levels. From a spatial standpoint, mercury levels in eggs appear to increase with latitude but enhanced data analysis techniques suggest that levels are highest in gull eggs collected from sites proximate to receiving waters of the Athabasca River.
Data for other heavy metals, PCDDs, and PCDFs do not reveal any patterns over space or time.
- Publisher - Current Organization Name: Environment and Climate Change Canada
- Licence: Open Government Licence - Canada
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