Growth zones in the otoliths and scales of Antarctic fish were investigated to determine during which period of the year they were formed. In otoliths, the opaque zones were formed during summer and autumn, and the hyaline zones during the winter, spring and early summer. In scales, the zone of widely spaced sclerites (circuli) was formed during summer and autumn, and the zone of closely spaced sclerites in winter. The hypothesis that an adjacent opaque and hyaline zone in otoliths, and an adjacent wide and closely spaced sclerite zone in scale, is an annulus, which represents one year of life, was supported by this study. It was concluded that counting such annuli is a valid technique to age Antarctic fish.