The results of the introduction of various forms of the European vendace Coregonus albula from Karelia’s donor lakes Munozero, Urosozero, Vendyurskoe, and Onega into recipient lakes Urosozero, Vashozero, Konchozero, and Pertozero in order to improve the composition and productivity of the fish fauna were analyzed. Vendace proved to have become naturalized in all the recipient lakes. Its biological parameters in the new habitats were studied. Comparative analysis of the length-weight growth and fecundity of vendace shows that all the lakes into which it was introduced are now inhabited by its large form. Vendace has formed highly abundant self-reproducing populations in all the lakes studied and has become a major target for commercial fishing. Previously, the recipient lakes exhibited only one flux of matter and energy: benthos – benthos-eating fish – predatory fish. Now, another one has developed: plankton – vendace – predatory fish. Due to the presence of different forms of vendace, food resources of the said lakes are utilized more fully.