LABORATORY OBSERVATIONS ON TODARODES PACIFICUS (CEPHALOPODA, OMMASTREPHIDAE) EGG MASSES

Two egg masses of the ommastrephid squid Todarodes pacificus (Steenstr up, 1880) are described. Immature squid were collected from inshore wa ters of southern Hokkaido, Japan, and maintained in a raceway tank whe re they matured, mated, and spawned. Both gelatinous masses were spher ical and nearly neutrally buoyant. The larger mass measured 80 cm in d iameter and contained approximately 200,000 eggs. The egg-mass surface layer effectively prevented crustaceans, protozoans, and bacteria fro m infesting the masses. Paralarvae hatched after 4-6 days at 18-19 deg rees C and actively swam at once, with many individuals swimming at th e surface. Both masses disintegrated soon after hatching. Paralarvae d ied approximately 6-7 days after hatching, presumably due to starvatio n.