Growth is a fundamental biological process in the dynamics of fish populations and is the basic parameter underlying characteristics such as stock biomass and size frequencies. Investigators of inter-annual variability in fish growth often use hard body part analysis, such as variability in otolith increment widths as a proxy for somatic growth. This study presents inter-annual variability of otolith growth in blue grenadier Macruronus novaezelandiae off the west coast of Tasmania from 1991 to 2011. Capture size at age data highlighted that M. novaezelandiae females grow larger than males with mean size at age statistically diverging by 3 years of age and remaining separated thereafter. In contrast, statistical differences in mean otolith increment widths at age between sexes were detected at earlier ages but these differences were lost after the age of 7. Inter-annual variation in mean otolith increment widths for the first four increment zones (juvenile zones) all showed a similar trend with declining increment widths from 2006 to 2010. Inter-annual cohort sex ratios across year-of-birth also varied (χ2 = 366.11, df40, p << 0.0001) and displayed a similar trend to the first year otolith increment growth profiles of both male and females. Correlation of birth year sex ratio with mean otolith increment widths indicated a highly statistically significant negative correlation with first year growth declining in both genders with increasing numbers of male offspring (Male: r(19) = 0.71, p < 0.001; Female: r(19) = 0.66, p = 0.001).