Sexual maturity of Splendid alfonsino (Beryx splendens) in the Emperor seamounts

    We analyzed biological data of splendid alfonsino Beryx splendens in the Emperor seamounts shared by NPFC Members to define the reproductive season and maturity stages and to estimate size at sexual maturity (FL50). Monthly changes in gonadosomatic index and maturity stages based on macroscopic and microscopic analyses suggests that reproduction occurs between March and December. The FL50 values estimated by a logistic regression model ranged between 257 and 365 mm. This differences in estimates may be related to differences in fish size used in the analysis, sampling location, and year. Therefore, further analysis considering temporal and spatial variability is needed to estimate more reliable FL50 for stock assessment of Beryx splendens in the Emperor seamounts area.

    Document Number
    NPFC-2022-SSC BFME03-WP06
    Document Version
    1
    Agenda Item
    Review of Members’ research and joint research activities on SA
    Authors
    Bungo Nishizawa and Kota Sawada
    JAPAN