BAUWENS P BAUWENS, L & RAHDER J (1976) Breeding case of a Crossbill Loxia curvirostra in Bilthoven, provo Utrecht. LIMOSA 49 (3): 201-203.

Common Crossbill Loxia curvirostra After a small invasion of Crossbills, a female was seen, building a nest in a wood near Bilthoven on the 2nd of February 1975. Various forms of courtship display were observed and copulation was also seen, near the nest. From the 13th of February till the 26th the eggs were incubated. After the hatching, the female sat on the young for another 13 days. After the 12th of March the nest seemed abandoned. The nest has been collected. The male was very likely a bigamist. Many other observations suggest that more Crossbills have bred in the same forest this year.

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