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Occurrence of pikeperch (Sander lucioperca (L.)) and its habitats in northeastern Poland in 1951-1994

100%

Skrzypczak A., Mamcarz A.

Archives of Polish Fisheries

2005

tom 13

nr 1

The study was conducted based on data from lake management books. Pikeperch, Sander lucioperca (L.), was present at various time intervals in 619 lakes in northeastern Poland that covered a total area of 116.2 thousand ha. Based on the frequency of occurrence of this fish species in commercial catches, three categories of habitats were distinguished. The morphologic and morphometric parameters of these three categories of lakes were compared. For each category, the dynamics of temporal changes was characterized in the lakes in which pikeperch lived, and the trend lines of these changes were plotted. An increase in the number of habitats of this predatory fish species appeared in 1951-1965 and was directly connected with its natural migration. The range of fish stocking measures and the time when they began were determined for the three categories of lakes analyzed.

Pikeperch (Sander lucioperca (L.)) exploitation in reference to stocking programs and the size structure of its habitats in northeastern Poland in 1951-1994

67%

Skrzypczak A., Mamcarz A.

Archives of Polish Fisheries

2005

tom 13

nr 2

The analyses were based on commercial fisheries records of catches and stocking in lakes in northeastern Poland. The authors described the lake size structure in three categories of pikeperch, Sander lucioperca (L.), habitats determined by the frequency of occurrence of this species in commercial catches. In each of the five lake size classes, the moment pikeperch individuals appeared was pinpointed in light of stocking programs. Differences in the value of pikeperch exploitation parameters were determined in the three habitat types, and the level of variation was examined in stocked and unstocked lakes. Trend lines of pikeperch exploitation in the 1951-1994 period were plotted for these groups of lakes. The importance of pikeperch stocking for the occurrence of this species in new habitats declined as the size of the studied lakes increased.

Ograniczanie wyników

2 Archives of Polish Fisheries

2 Mamcarz A.

2 Skrzypczak A.

2 2005

Wyniki wyszukiwania

Occurrence of pikeperch (Sander lucioperca (L.)) and its habitats in northeastern Poland in 1951-1994

Pikeperch (Sander lucioperca (L.)) exploitation in reference to stocking programs and the size structure of its habitats in northeastern Poland in 1951-1994