EN
As a key ecological and economic species, the eel plays a decisive role in the profitability of fisheries enterprises. The population of eel in Polish waters has declined substantially in the last decade, which has had a negative impact on the finances of fisheries enterprises. This is apparent from the analysis of commercial catches and stocking programs based on data taken from lake logs from the 1973-2004 period and from recreational catches based on data taken from records and angler surveys from the 2004-2006 period. The analysis focused on 70 lakes in the Oder River basin with a total surface area of 19,809 ha. The annual decrease in eel catches in the Oder River basin during the 1973-2004 period was 3.03%. The mean annual eel CPUE early in this period (1973-1982) was 2.40 kg/ha, while in the 1995-2004 it was 1.01 kg/ha. Eel stocking also decreased significantly, especially that of the glass eel, from the maximum intensity in the mid 1970s to the near cessation of stocking this form of eel since 1996. Recreational catches in the waters of the Oder River basin are estimated to be 106.3 tons.