Recordings of mature Gonatus fabricii (Lichtenstein) off the Norwegian coast

Abstract

Two mature female and three mature males were sampled by trawling with a pelagic trawl at depths of more than 800 m off northem Norway. A third female were sampled with bottom trawl at 970 m off mid Norway. The females had a flabby, swollen appearance and degenerated tentacles and from 5 to 12 mature eggs on the ovary. The mature eggs had a largest diameter varying from 4 to 6 mm. The females were all larger than the mature males and the smallest had a DML of 260 mm. The females seems to mature at lengths between 200 and 250 mm. The mature males had spermatophores, 7 to 9 mm long, in the spermatophoric sac and in the penis, showing that they had not copulated. The smallest male had a DML of 190 mm. The males seems to mature at smaller length than the females. Assuming the same growth rate as observed at West Greenland, Gonatus fabricii seems to mature at an age of 2 to 2,5 years. Other recordings of larger mature males could indicate a second mating at an age of three years. The recordings of mature females at bottom indicate spawning at bottom. Recordings of mature females from summer to end of November indicate that spawning takes at least place during this period. The recordings of mature females at bottom indicate spawning at bottom. Recordings of mature females with emty spermatophores more than 500 m above bottom arise questions of a second mating or pelagic spawning.