Centropyge bicolor tend to be moderately aggressive, both to members of other species and members of their own species—even their own group. The male spends most of his time guarding his territory from predators, intruding members of other species, but mostly against another harem. This territory tends to be a maximum of 200m2 and encompasses the home ranges of all females within the group. Females are only aggressive towards lower-ranking members of their own group, in order to maintain their current rank.
