All blue gropers begin life as females. As they mature, they go through an initial phase, in which they may be male or female, before developing their adult colouring and reaching the terminal phase.

Typically you will only find one or two male blue gropers in an area, with a larger number of the female gropers in the same area. Should the dominant male blue groper die, the largest female will grow, change colour and sex, and become the dominant male.