The aim of the study was to compare the effects of intraperitoneal (group P) and intramuscular (group M) methods of implanting PIT tags on the growth, condition, and survival of juvenile pikeperch, Sander lucioperca (L.) (body weight about 82 g) and tag retention. After tagging, the fish were held in recirculating aquaculture systems (RAS) and reared on commercial feed for 56 days. No significant differences were noted in fish growth rate or condition between the experimental groups (groups P and M) and the control group that was not tagged (group C; P > 0.05). The feed conversion ratios were also of similar values (FCR - 1.2-1.3; P > 0.05). Tagging did not impact fish survival, which was 98.9% in group P and 100% in groups M and C on the final day of the experiment (P > 0.05). Tag retention in both groups was also 100%. The results of this study confirm that both tagging methods are suitable for juvenile pikeperch. The PIT tags were noted to migrate in the body cavity in group P (47.2% of tagged fish). Accordingly, the intramuscular method for implanting PIT tags is recommended for juvenile pikeperch (body weight > 60 g).
