Convict Cichlid - Reproduction

Reproduction

The species can reach sexual maturity as young as 16 weeks, though sexual maturity more commonly occurs at 6 months. Sexually mature convicts form monogamous pairs and spawn in small caves or crevices. In the wild, the fish excavate caves by moving earth from underneath large stones. Females lay the eggs on the upper or side surfaces of the cave to which they adhere.

Like most cichlids, convicts brood (exhibit parental care of) both eggs and free-swimming fry. The eggs hatch approximately 72 hours after fertilization, and during that time the parents expel intruders and potential egg predators from around the nest. They also fan the eggs, moving water with their fins over the clutch to bring oxygen to the eggs. They fan the eggs both day and night; at night they use their sense of smell to recognize the presence of the eggs in the dark, and they keep their pelvic fins in contact with the eggs to remain at the right distance for fanning. At night the parents also recognize each other via their sense of smell, and they sniff out and react to the presence of potential predators in or near the nest.

After hatching, a further 72 hours is required for the larvae to absorb their yolk sacs and develop their fins prior to becoming free-swimming fry. While in this free swimming stage, fry forage during daylight in a dense school and return to the cave or crevice for the night. Like other cichlids, the parents also retrieve their young just before dark, sucking up three or four fry at a time into their mouth, swimming back to the nest, and spitting the young into it. The parents do this in anticipation of night arrival, using an internal time sense to know that night is approaching, as shown by laboratory experiments in which convict cichlids continued to retrieve even before nights that were not preceded by any signal such as dim light. During the night, the fry bunch up at the bottom of the cave or nest, where the parents fan them.

Both parents remain involved in guarding the fry from brood predators and engage in behaviors to assist feeding such as moving leaves or fin digging (digging up the substrate with their fins). Brood care of eggs, larvae and free-swimming juveniles in the wild can last 4–6 weeks, and occurs only once per season for the majority of females. In contrast, females in aquariums are known to breed many times per year with short intervals of 12–13 days between broods, as long as suitable rocks or similar surfaces are available for them to lay their eggs on. In captivity, breeding pairs of convict cichlids have been demonstrated to adopt similarly aged fry from other parents. In other cichlids it has been suggested this behavior may reduce predation on the fry belonging to the adoptive parents, through a dilution effect.