FEMALE AGGRESSION AND MALE PEACE-KEEPING IN A CICHLID FISH HAREM - CONFLICT BETWEEN AND WITHIN THE SEXES IN LAMPROLOGUS-OCELLATUS

Conflicts of interest within and between the sexes are important proce sses leading to variability in mating systems. The behavioral interact ions mediating conflict are little documented. We studied pairs and ha rems of the snail-shell inhabiting cichlid fish Lamprologus ocellatus in the laboratory. Due to their larger size, males controlled the reso urce that limited breeding: snail shells. Males were able to choose am ong females ready to spawn. Females were only accepted if they produce d a clutch within a few days of settling. When several females attempt ed to settle simultaneously the larger female settled first. Females w ere least aggressive when guarding eggs. Secondary females were more l ikely to settle when the primary female was guarding eggs. In establis hed harems females continued to be aggressive against each other. The male intervened in about 80% of female aggressive interactions. Male i ntervention activity correlated with the frequency of aggression among the females in his harem. The male usually attacked the aggressor and chased her back to her own snail shell. When a male was removed from his harem, aggression between females increased immediately and usuall y the secondary female was expelled by the primary female within a few days. Time to harem break-up was shorter the more mobile the primary females' young were and did not correlate with the size difference bet ween harem females. Male L. ocellatus interfere actively in female con flict and keep the harem together against female interests. Female con flict presumably relates to the cost of sharing male parental investme nt and to the potential of predation by another female's large juvenil es on a female's own small juveniles.