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Methylmercury: Reproductive and behavioral effects on three generations of mallard ducks

G. H. Heinz
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Abstract

Three generations of mallard ducks ( Anas platyrhynchos ) were fed either a control diet or a diet containing 0.5 ppm mercury in the form of methylmercury. The levels of mercury in adult tissues and eggs remained about the same over 3 generations. The methylmercury diet had no effect on adult weights or weight changes during the reproductive season. Females fed a diet containing 0.5 ppm mercury laid a greater percentage of their eggs outside their nestboxes than did controls, and also laid fewer eggs and produced fewer ducklings. Methylmercury in the diet appeared to result in a small amount of eggshell thinning. Ducklings from parents fed methylmercury were less responsive than controls to tape-recorded maternal calls, but were hyper-responsive to a frightening stimulus in avoidance tests; there were no significant differences in locomotor activity in an open-field test.

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BibTeXRIS

G. H. Heinz. 1979. Methylmercury: Reproductive and behavioral effects on three generations of mallard ducks. https://doi.org/10.2307/3800348

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