BIOMETRICAL CHARACTERIZATION OF BLEAK (ALBURNUS-ALBURNUS) FROM THE VESTONICE RESERVOIR, CZECH-REPUBLIC

A biometrical study of bleak (Alburnus alburnus) from the Vestonice Re servoir demonstrated the importance of the environment influence on se veral plastic and meristic features in the population under study. In comparison with mean feature values for European populations studied t o date, we found higher values in body height, head length, fin size, number of branched rays in D and A, and on the contrary, lower values in scale number of the lateral line and tail stylet length. Changes in variability range and mean values of meristic and plastic features ar e documented and evaluated. Based on morphometric characters of the bl eak, environmental conditions of the reservoir seems to be ecologicall y closer to the European locations situated more southerly.