| Summary: | The yields in the Møre and Lofoten skrei fisheries have varied independantly, i.e, good yields in one spawning area do not necessarily coincide with good yields in the other. Tagging results from the two areas have indicated two separate spawning populations as most of the mature fish return to the earlier visited spawning area, To further analyse the evidence of two separate skrei spawning populations, year class strength, growth and sex distributions of skrei in samples from commercial gill net catches from Møre and Lofoten during the period 1974-1981 have been studied, The results indicate that the two spawning populations are not necessarily dominated by the same year classes, It is also observed that the part of older fish (> 9 years) is more abundant in the Møre than in the Lofoten catches, During the years 1974-1978, the mean lengths of the age groups 6-9 years were significant higher in the Møre catches while there were no significant length differences in any age group during the years 1979-1981, The observed change in 1979 is suggested to be connected with climatic changes in the Barents Sea. For all years and all age groups, exept six years old skrei, the proportion of females was 1-16% higher in the catches from Møre, It is concluded that the observations support previous tagging results which indicated two separate sub-populations of Norwegian-Arctic cod connected to the two spawning areas Lofoten and Møre, The recruiting mechanism to the two areas is not yet known
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