Sousa tueszii is polygynous, as a single male mates with multiple females. Calving has been reported from December to February, but may extend into other months. The exact age of sexual maturity is unknown, but most individuals reproduce between the ages of 4 and 8. The closely related Sousa chinensis breeds year round, although calves are typically born during the summer. In other dolphin species, such as Tursiops truncatus (bottlenose dolphins), mating season occurs from March through April, and calves are born between February and May. Gestation lasts for approximately 12 months and young remain close to their mother until they are about 4 or 5 years old. In Tursiops truncatus, most individuals reach sexual maturity between 5 and 12 years of age for females, and between 9 and 13 years of age for males.
Mating System: polygynous
Little information exists regarding the reproductive behavior of Sousa tueszii. Calving has been reported from December to February, but may extend into other months. The exact age of sexual maturity is unknown, but most individuals reproduce between the ages of 4 and 8. Sousa tueszii has an average of one offspring per cycle, which weighs between 9 and 11 kg. Weaning has been reported in individuals as young as 24 months but usually is completed by 48 months. In the closely related Sousa chinensis, males often court females by somersaulting, chasing them in circles, and waving their flippers. In other dolphin species, such as Tursiops truncatus, males aggressively engage females during mating season and use a social hierarchy system based on size to determine which individuals mate.
Breeding interval: Sousa tueszii breeds once yearly.
Breeding season: Sousa tueszii breeds during April or May.
Average number of offspring: 1.
Average gestation period: 12 months.
Range birth mass: 9 to 11 kg.
Range weaning age: 24 (low) months.
Average weaning age: 48 months.
Range time to independence: 4 to 5 years.
Range age at sexual or reproductive maturity (female): 4 to 7 years.
Range age at sexual or reproductive maturity (male): 4 to 7 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous
There is no information available regarding parental care in Sousa teuszii. In other dolphin species, such as Tursiops truncatus and the closely related Sousa chinensus, gestation lasts for approximately 12 months. In these species, calves become completely independent when they are approximately 4 to 5 years old. Until the calf reaches sexual maturity, it remains close to the mother.
Parental Investment: pre-hatching/birth (Provisioning: Female, Protecting: Female)
- 2010. "Sousa teuszii" (On-line). Accessed March 14, 2011 at http://www.cms.int/reports/small_cetaceans/data/S_teuszii/s_teuszii.htm.
- 2011. "The Shark Bay Dolphin Research Project" (On-line). Georgetown University Department of Biology. Accessed April 21, 2011 at http://biology.georgetown.edu/faculty/mann/research/.