Removal of egg-tending males in a monogamous goby, Amblygobius phalaena, was performed on coral reefs of Okinawa, Japan. All five removal experiments led to shifts of parental care to the paired females, and two of the females continued egg care until just before the eggs hatched. Evolution of the shift of parental care to a non-caregiving parent in this species may be facilitated by the spatial closeness between mates after spawning and no necessity of special structures and organs for guarding care.