Distribution, growth and exploitation of greater silver smelt (Argentina silus (Ascanius, 1775)) in Norwegian waters 1980-83

Abstract

Greater silver smelt (Argentina silus) occurs regularly in Norwegian waters, near bottom over large areas of the continental shelf. Due to a directed fishery for human consumption off mid-Norway, the stock was regularly monitored every spring and autumn. Data on distribution and abundance, as well as age, length and sexual maturity formed the basis for evaluation of the state of the stock and were applied for management advice to prevent overexploitation. During the spring, greater silver smelt is more congregated at the continental slope and in the deeper parts on the shelf, while during the autumn it is mostly scattered over large areas. Immature specimens occur mainly at depths of less than 300 m, and the mature individuals predominate at greater depths. Within specific areas, the age and length compositions vary between seasons, and hence growth variations from area to area were difficult to point out. However, there was a tendency for increased maximum length at increased latitude, and females were generally larger-at-age than males. The age at first sexual maturity occurs at a wide age range of 4-12 years, with 7 years as the mean age for male and 6 years for female maturation. The sex ratio was about equal in shallow areas, but males frequently dominated at greater depths.