The study concerning waterfowl of two neighbouring fishponds complexes – in Bestwina and Komorowice villages near Czechowice-Dziedzice – was carried on in the years 1995–1999. The ponds are situated in the western part of the Upper Wistula Valley that is a waterfowl refuge of European importance (Heath, Evans 2000). There are over 60 small reservoirs in Bestwina, with total surface 80 ha. In Komorowice 18 ponds occupy also about 80 ha (Fig. 1). The Goczałkowicki Reservoir, an important site of waterfowl, is located not far from the research area. The fishponds are fed with waters of the tributaries of the Biała river, running in the distance of 50–150 m to the west of them. The ponds are poorly overgrown by rush vegetation, with dominating Phragmites australis and Typha latifolia. Altogether 85 controls were done; the waterfowl censuses were estimated according to the methods described by Borowiec et al. (1981) and Ranoszek (1983). The number of 55 species related to wetlands, including 28 breeding or probably breeding species were recorded. However, as much as 14 of them were nesting sporadically or irregularly (Tab. 1). In spite of relatively poor breeding waterfowl population, a few broods of such endangered on European scale (acc. to Tucker et al. ed. 1994) species as Ixobrychus minutus, Nycticorax nycticorax (?), Anas strepera, Anas querquedula, Anas clypeata, Aythya ferina, Tringa totanus, Alcedo atthis, Acrocephalus scirpaceus, Emberiza schoeniclus were recorded. The described fishponds complexes have a low importance for breeding and passage birds in Silesia. According to Stawarczyk (2001), their rank is small. However, every 5 years, twice a breeding season, controls of the site should be done.
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