THREATS TO THE ICHTHYOFAUNA OF THE MAGURSKI NATIONAL PARK AND ITS SURROUNDINGS
University of Rzeszów, Faculty of Mathematics and Natural Sciences, Rzeszów, Poland
ABSTRACT. Fifteen sites were selected in the upper Wisłoka River drainage basin. Twelve species were recorded. In terms of abundance the dominant species in the material collected were Phoxinus phoxinus (L.), Leuciscus cephalus (L.) and Barbus peloponnesius Val. P. phoxinus clearly dominated in the smallest streams and there were significant local contributions of Salmo trutta m. fario L. to the fish biomass. In the larger streams, the minnow contribution decreased while chub and spotted barbel dominated in the biomass. Spirlin Alburnoides bipunctatus (Bloch) was also relatively abundant. Among the trout caught, relatively small specimens dominated. Poaching was most probably responsible for the lack of larger specimens in the samples. The small impoundment on the Wisłoka River and changes in stream beds caused by gravel exploitation, regulation and forestry management works also had an adverse impact on the ichthyofauna of the studied basin.
Key words: FISH, MOUNTAIN STREAMS, POACHING, THREATS
Krzysztof Kukuła, Uniwersytet Rzeszowski, Instytut Biologii i Ochrony Środowiska, ul. Rejtana 16a, 35-310 Rzeszów; Tel./Fax:+48 17 8625628; e-mail: firstname.lastname@example.org