DIRKSEN S (1996) Short contributions: Numbers ofRed-crested Pochard Netta fUfina on the Gouwzee in late summer and autumn vary with breeding success Dutch population. LIMOSA 69 (3): 131-133.

Red-crested Pochard Netta rufina In recent years relatively high numbers of Red-crested Pochard have been feeding on stoneworts in Lake Gouwzee (Lake IJsselmeer area, The Netherlands). After a period of absence, stoneworts have recently recolonized several shallow lakes in The Netherlands as a result of improving water quality. The ducks visit the area from July - November, with a peak in September-October. Maximum numbers varied between years. The variation in this maximum corresponds to data on the number of breeding pairs and on breeding success in the main Dutch breeding area (Vinkeveense Plassen and surroundings). Furthermore, the highest number of birds counted in Lake Gouwzee in autumn 1995 (140) was in accordance with the estimated total of breeding birds and their offspring (37-48 pairs, total of 150-170 birds). Therefore it doesn't seem necessary to assume that birds from other European breeding areas visit the Dutch stonewort fields, as used to be the case in the 1950's and 1960's. The Dutch breeding population of Red-crested Pochards is slowly increasing with the recovery of aquatic vegetation. In the near future, Red-crested Pochards from other breeding areas might also find their way to the expanding Dutch stonewort fields again.

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