No information was found on the mating systems of M. australis.
Miniopterus australis start to reproduce after 21 months of age. Copulation activity occurs during the winter months of June and July. Once mated, the females do not store the sperm; fertilization takes place right away in August. Although there is no delayed implantation, retarded embryonic development is experienced. The retarded development lasts from August to mid-September, when normal development resumes.
Miniopterus australis, like M. schreibersii, chooses specific sites for nurseries in which to rear young. These nurseries are used year after year, with both species often together in one site. Miniopterus australis gives birth in the summer month of December after a gestation period of about four months.
Although no reports were found for M. australis, newborn M. schreibersii weigh between 2 nd 3 g. Weaning of M. schreibersii occurs at about 2 months of age. Miniopterus australis is probably similar.
Breeding interval: These bats appear to breed annually.
Breeding season: Breeding occurs in June and July.
Range number of offspring: 1 to 1.
Range gestation period: 180 to 195 days.
Average age at sexual or reproductive maturity (female): 21 months.
Average age at sexual or reproductive maturity (male): 21 months.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous ; embryonic diapause
Miniopterus australis is considered a juvenile up to 9 months, a yearling between 9 and 21 months, and an adult after 21 months of age. Mothers tend to the young, nursing and grooming them, but sometimes find that the cave becomes too warm. To cool themselves off, the mothers will leave the young hanging alone in the cave amd exit to the cool outdoors. Male parental care has not been described in this species.
Parental Investment: no parental involvement; altricial ; pre-fertilization (Protecting); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Protecting: Female)