Abstract
Fish catches were carried out in 1996-1997 in old beds of the Vistula River, along a 40 km stretch from Kazimierz Dolny to Dêblin, as well as along Wieprz (right-hand tributary of the Vistula) and Tyoemienica (right-hand tributary of Wieprz) rivers to find an East-Asiatic fish Perccottus glenii. 15 stations were selected along the Vistula, and 9 along the Wieprz and Tyoemienica. It was found that P. glenii was a popular fish in old Vistula beds, but it did not inhabit Wieprz and Tyoemienica rivers.