Dugong (Dugong dugon) are air-breathing marine mammals of global conservation significance, that can grow up to three metres, weigh up to 400kg and live for at least 70 years. Females reach sexual maturity at six years, and produce a calf only once every 2.5-5 years thereafter. Gestation period is 14 months, but calves suckle milk from their mothers for 18 months after birth. Dugongs’ main food source is seagrass, but they also eat invertebrates such as worms, sea squirts, and shellfish.