hree 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.