The breeding period of Sumatran rhinoceroses is not well-documented. Rhinoceroses, in general, do not have rigid breeding periods, and breeding can potentially occur throughout the year. Factors such as environmental conditions and female reproductive cycles may influence increased breeding activity. Sumatran rhinoceroses have a lengthy gestation period of about 15 to 16 months, and females typically have a period of infertility after giving birth before becoming receptive to breeding again. However, due to their critically endangered status, specific details about the breeding season of Sumatran rhinoceroses remain limited, emphasizing the importance of conservation efforts and further research.