Growth production and reproduction of the myctophid fish benthosema glaciale from western norway and adjacent seas
Fiskeridirektoratets Skrifter Serie Havundersokelser 17(3): 79-108
Age, growth, mortality, production and reproduction were studied on material of B. glaciale from some fjords of western Norway and from the adjacent ocean. Samples were collected using pelagic trawls and Icaacs-Kidd midwater trawls. Age was studied by means of otoliths although the seasonal cycle of zone formation was variable. Growth was highly variable within the material, L.infin. of the von Bertalanffy's growth equation ranging from 70-87 mm and K from 0.19-0.46. The instantaneous natural mortality was .apprx. 0.7. The maximum sustainable yield per recruit can be obtained with a 1st age of capture of .apprx. 2 yr and a fishing mortality of 1.5 or higher. B. glaciale reaches maturity at an age of 2-3 yr and spawn mainly during summer. The development of the ovaries is briefly described. Mean fecundity is 700 eggs/female.