herring migrations was not carried out on a scientific scale, because the fishing itself was on a 

 small scale. Now that herring fishing is a year-round industry, tagging is the most effective 

 method for establishing the migration paths of herring. In view of this, the Polar Institute set up 

 tagging experiments in 1953, using herring from the White Sea. When selecting the type of tag, 

 the technique and organization of fishing, as well as the methods of processing, must be kept In 

 mind. 



Internal abdominal tags undoubtedly offer numerous advantages; however, this method can 

 be employed only where there are special magnetic installations for detecting the tags . 



A±)dominal tagging of herring Is highly effective in a fishery which supplies large oil- 

 rendering plants (Alaska, Norway, Iceland). Abdominal tags cannot be used In our fishing indus- 

 try where the fish are salted on board the ship and, at the end of the cruise, delivered in barrels 

 to the floating or shore bases. The use of these tags would require installation of special magnet- 

 ic Instruments on board all the ships, which would greatly complicate herring-processing opera- 

 tions . 



Therefore, the herring laboratory of the Polar Institute chose the external type of tag, 

 which, we found, the herring tolerate quite satisfactorily. These tags are clearly noticeable, 

 which ensures a high tag return. 



Tagging experiments were set up in 1953 and 1954 In Kandalaksha Bay. Apart from enabling 

 us to solve the problems connected with the organization of tagging of oceanic herring on Soviet 

 fishing grounds, tagging of White Sea herring provided us with interesting data on their migrations. 



Small Kandalaksha herring were tagged during their spawning movements toward tlie shores. 

 The tagging was carried out in Valas-Ruchey and Zhemchuzhnay inlets of Kandalaksha Bay. 



Herring were obtained from traps during the test fishing. 



In 1953, we used tags made in the form of red plastic plates 20 mm. x 8 mm. in size. On 

 one side, the tag bore an inscription of Its Index number in China ink, on the other U.S.S.R. The 

 inscriptions were coated with a thin layer of acetone varnish. 



A nickel wire 0.5 mm. in diameter was threaded through the edge of the plate, then attach- 

 ed to the back of the herring 1 cm. in front of the dorsal fin (Figure 1). In 1954, we used identical 

 tags; however, they were made of pink celluloid, and the index and U.S.S.R. were not inscribed, 

 but stamped. 



Wooden blocks were used (Figure 2) to keep the fish In water during tagging. The front 

 section of the block where the head of the fish is placed must be closed. In the region of the dorsal 

 fin, the block has openings through which the tag can be attached without hindrance. Tagging blocks 

 of different sizes must be available because of the varying lengths of fish. 



The tagging was done In the following manner: live herring were transferred from traps in- 

 to a water pail, carried to the tagging place, and carefully transferred to a "net tank" whence the 

 fish were removed one by one, placed Into tagging blocks containing water, then tagged. Having 

 fastened the tag, the fish were carefully released into an ice hole. Herring survived the tagging 

 satisfactorily, when the operation was performed correctly and rapidly. After the tagging oper- 

 ation was completed, the fish moved rapidly to the depths. Fastening the wire to which the tag is 

 attached to the direct proximity of the spinal column is lethal to the fish; therefore, the wire must 

 be fastened to the upper dorsal region. Herring are not harmed when tags are attached behind the 



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