LE3 .A278 2013

2013

Mallory, Mark

Acadia University

Bachelor of Science

Honours

Biology

Biology

Although the Canadian Arctic appears to be a region removed from the harmful effects of pollution, environmental contaminants occur in significant concentrations, particularly in marine ecosystems. Mercury (Hg) levels especially have been of increasing concern in the Canadian Arctic. Current attempts to quantify bio-accumulated mercury often involve invasive sampling methods. The objectives of this study were to determine: (a) whether Hg was higher in feathers from top avian predators and scavengers than species feeding lower in marine food chains, similar to patterns found in their eggs; and (b) whether the non-invasive method of sampling feathers is an appropriate alternative to invasive methods. Methyl Hg and total Hg levels were determined from feather samples of six species of Arctic marine birds: Thick-Billed Murre (Uria lomvia), Northern Fulmar (Fulmarus glacialis), Black-Legged Kittiwake (Rissa tridactyla), Ivory Gull (Pagophila eburnea), Glaucous Gull (Larus hyperboreus), and Common Eider (Somateria mollissima borealis). Consistent with my hypothesis, Hg levels were markedly greater in feathers for species that fed higher in the food web in Arctic marine environments. The ratio of methylmercury to total mercury concentrations was surprisingly low in Ivory Gull samples, a result possibly related to photodemethylation in semi-opaque tissues. Consequently, sampling feathers for mercury concentrations appears to be a suitable alternative to employing invasive methods to assess and monitor mercury concentrations.

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https://scholar.acadiau.ca/islandora/object/theses:1017