BEKHUIS J (1990) How long will Little Bitterns Ixobrychus minutus breed in The Netherlands?. LIMOSA 63 (2): 47-50.

In the 1960's, an estimated 175-225 pairs of the Little Bittern bred Ixobrychus minutus in The Netherlands, but probably the estimate was too low. Breeding bird surveys in later years revealed a dramatic decrease: 100-135 pairs in 1973 - 1977, 35-75 pairs in 1982 - 1983 and 20-30 pairs in 1988 - 1989. Changes in the distribution are shown in figure 1. Population changes in intensively studied areas are demonstrated in figure 2. Deterioration (water pollution, recreation) and loss of habitat may have been important factors. However, the well-documented contraction of the breeding range all over Western Europe indicates that determining factors are not of a local or national impact. It is suggested that part of the main causes may be related to the situation in the migration and wintering areas.

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