RIEDSTRA BJ (1997) Two anomalous broods of the Marsh Harrier, Circus aeruginosus. LIMOSA 70 (1): 33-33.

In the course of a census of Marsh Harrier nests in Lauwersmeer, northern Netherlands, in 1994, aberrant situations were found in two nests. First, three eggs were added to a clutch of six at the time that the first young of the original clutch had hatched. Since all three additional eggs were consistently smaller than eggs of the original clutch (Tab. I), it is presumed that the additional eggs were laid by one single different female. In the second case, a third calender year female laid three eggs, two of which were considerably smaller (viz., 42.8x29.6 and 46.8x32.4 mm) than average egg-size in the Lauwersmeer- population (49.lx38.0 mm, N=234).

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