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The paper reports results of a study on the population of vimba in the Rega River aimed at localisation of the spawning sites and support of the natural reproduction by stocking. The spawning sites were localised with the help of electric catching and the coordinates were determined by GPS units. The fish caught to be used for artificial spawning (145 individuals) were measured (l.t. and l.c.) using an electronic calliper coupled with a PC unit. The sex of the fish was identified and on the basis of scale analysis the age and rate of length and mass increase were estimated. The backcalculation readings were made using the Rosa Lee method. The model of growth was established on the basis of the von Bertalanffy formula. Comparisons of groups of fish were drawn with the help of the nonparametric Mann Whitney U test. Correlations between variables were evaluated by analysis of regression, while the significance of the correlation coefficient was checked by t test. The rate of vimba mass increase was calculated using the modified von Bertalanffy formula was found to be described by Wt = 1215.103[1-e-0.133609(t+0.57322)]2.7559. The spawning sites of vimba localised in the Rega River section between Gryfice and Trzebiatow were concluded to be good sources of spawners for artificial spawning and the number of spawners caught in this section of the river ensures continuation of vimba restitution in the Rega River. The hitherto stocking measures aimed at restoration of vimba population have brought satisfactory results as evidenced by the age structure of the fish caught in the electric fishing in 2008.
Key words: biogeography, threatened species, vimba, Vimba vimba, stocking, restoration, spawning sites