of the sea. The latter fish may remain within the borders of their initial range for one, two or 

 three years longer . 



Norwegian fisheries statistics separate sexually immature herring into a separate class, 

 the so-called "fetsild", i.e. fet herring. The latter differ from the small herring (the "smaasild") 

 in size and greater fattlness; from adult herring ("storsild" and "vaarsild") - in the condition of 

 the gonads. Thus, "fat herring" form a definite biological group of fish 16-18 cm. to 24-25 cm. 

 in length, between the age of three years and the age at which they become sexually mature . These 

 fish are characterized by high fat content of muscular tissues and a great quantity of oil in the body 

 cavity . Gonads of fat herring are at the II-IV stage of development according to the seven-point 

 system. In the Norwegian Sea, the herring at this stage of development change to the marine mode 

 of life, leaving the littoral waters. In Barents Sea, fat herring migrate to the western region, 

 approaching the spawning grounds . 



o 

 In Norwegian waters, the fishery for fat herring is particularly intensive between Alesund 



and Lofoten Islands and has a coastal character; great quantities of fat herring are caugjit in fjords. 



Fishing for fat herring is conducted along almost the entire Norwegian coast, excluding its 

 most northerly provinces . The main regions of intensive fishing for fat herring are situated to the 

 south from the region where small herring are caught in great quantities, which is undoubtedly 

 related to the southward movement of fat herring. 



The migration scheme for young Norwegian herring suggested by Meek (59) shows that the 

 general direction of the movement is towards the south. According to this scheme, herring pro- 

 ceed into the op>en sea in winter, approaching the shores in summer. Distances covered during 

 these periodic migrations increase with age. In their fourth or fifth year, herring appear in the 

 spawning grounds off the south-western shores of Norway. Migration of young Norwegian herring 

 into the North Sea is rather improbable, according to the scheme of Meek. 



According to the Scheme suggested by Lea (56), fat herring leave the littoral waters a year 

 or two before they attain sexual maturity and proceed into the open sea, where, northerly from the 

 Faeroes, they undergo the so-called oceanic stage. Having matured sexually, they proceed from 

 the above region to the south-western shores of Norway. The fact that fat herring move into the 

 open sea and not along the shores has been further confirmed by the experience of the Norwegian 

 fishing industry . 



The course of fat herring movement off the shores of Noirway and into the open sea has been 

 shown by a marked herring (No. 1656), released on September 7, in the region of Lofoten Islands 

 (68°25' north latitude) and caught again in the vicinity of Helgoland Ridge (16 55' north latitude, 

 3°08' east longitude). 



Lea's scheme introduced an additional factor that has been omitted by Meek. Lea pointed 

 out that; because of a faster growth rate and early sexual maturation, the fat herring leave the 

 southern regions of Norway earlier than the herring from noirthem regions . The specimens that 

 developed in the southern regions of Norway attain sexual maturity as a rule at the age of 4 and 5 

 years, occasionally even at the age of 3 years; in the northern zone, however, the majority of 

 herring mature at the age of 5-6 years. Runnstrom (66) expressed the supposition that Norwegian 

 herring undergo the oceanic stage mainly in the zones of vortices formed by the Norwegian current. 

 No special observations on the distribution of fat herring beyond the borders of the Barents Sea have 

 been set up thus far. The data on this group were obtained as a result of experimental fishing with 

 drift nets with a mesh of 30-32 mm. Experience has shown that the herring 22-24 cm. in length 

 become entangled in the nets with 32-34 mm. mesh size. We frequently observed 23-24 cm. fat 



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