SOME ASPECTS OF THE BIOLOGY OF TODARODES SAGITTATUS (CEPHALOPODA, OMMASTREPHIDAE) FROM THE BALEARIC SEA (WESTERN MEDITERRANEAN)

A total of 346 individuals (152 males and 194 females) of Todarodes sa gittatus caught by commercial trawlers working down to 800 m in the Ba learic Sea (Western Mediterranean) was studied. Data are presented on size frequency distributions, length weight relationships, and relatio nships between mantle length and various measurements of the beak. Som e aspects of the reproductive biology (maturity and gonad development) were also determined. Reproductive period could be situated in the se cond half of the year, since the number of mature individuals was maxi mum from July to October for males and from September to December for females, The sex ratio was found to be significantly different from 1: 1 only outside this second semester. No individual appeared in hauls p erformed below 100 m depth and the greatest frequency of appearance wa s between depths of 400 and 800 m. All mature females were caught deep er than 500 m, indicating that spawning could take place from this dep th. The mean mantle length increased with depth, suggesting a possible ontogenic migration.