CALANOIDES-ACUTUS IN GERLACHE STRAIT, ANTARCTICA .1. DISTRIBUTION OF LATE COPEPODITE STAGES AND REPRODUCTION DURING SPRING

Calanoides acutus (Giesbrecht) in 0 to 290 m stratified samples collected repetitively at 23 stations in Gerlache Strait, Antarctica, in November 1989 consisted of stage III to VI copepodites (CIII to CVI). All stages except CV decreased in abundance through the 3.5 wk sampling period. Vertical distributions of all copepodite stages remained consistent, with no evidence of diel vertical migration. Centers of mass were as follows: female CVI, 44 m; CV, 66 m; CIV, 127 m; male CVI, 189 m. Progressive ovarian maturation in adult females was not correlated with ambient chlorophyll a concentrations. Mean daily egg production at 16 stations over a 3 d period in late November was a hyperbolic function of 0 to 150 m integrated chlorophyll a concentrations.