A unique case of finding a large number of conjoined twins of juvenile pink salmon

Abstract

During the fish feeding studies in the Obutanai River (Sakhalin, Nevelsk district) in the time of juvenile salmon migration in May 2021, the pink and chum juveniles were found in stomach of white-spotted char (weight 72.3, 55.7 and 73.9 g) in the number of 21, 35 and 51 specimens, respectively. Among them, there were 3, 4 and 8 pairs of conjoined twins of pink salmon, obviously preyed recently and practically at the same time. It can be assumed that the conjoined twins of pink salmon were presented on the feeding grounds of char in significant numbers and developed synchronously with ordinary juveniles, so they were able to join the downstream migration.