Preliminary analysis of sablefish (Anaplopoma fimbria) otolith measurements from Northern Pacific in 1984

Abstract

Sablefish otoliths (sagittae) collected from four areas (Northern California, Gulf of Alaska, Bering Sea, and Aleutian Islands) in 1984 were used to determine age by the section otolith aging method, and to measure otolith radius and thickness. The relationship between oto­lith ratio (radius/ thickness) and age was linear in the four areas. There was no statistical dif­ference in the comparison of the age-otolith ratio relationship between the Gulf of Alaska, Bering Sea and Aleutian area; however, that of Northern California was found to be significantly differ­ent from the other three. These results are in keeping with the two-population hypothesis of pre­vious tagging studies. Thus, sablefish otolith measurements might be a sensitive characteristic for discerning sablefish population structures. Further studies of otolith morphometric analysis including shape might provide an even clearer picture of sablefish populations.