Induced parental care in male convict cichlid fish.

Three parameters of parental care were recorded for pairs of cichlid fish (Cichlasoma nigrofasciatum) caring for their own young to determine the normal parental role of the male. Nonreproductive adult males were induced to exhibit parental behavior (e.g. herding, fin-digging, and defense of young) by daily presentation of free-swimming conspecific young. This process of sensitization to young appears to be species-specific in that males did not exhibit parental care toward alien (Hemichromis bimaculatus) young. Parental behavior in reproductive and nonreproductive males, as well as the implications and function of sensitization in these fish, is discussed.