Dugong

The dugong (Dugong dugon) is the only living member of the family Dugongidae and the sole strictly marine herbivorous mammal, spending its entire life in saltwater coastal habitats across the Indo-Pacific. It grazes almost exclusively on seagrass, preferring low-fiber, high-nitrogen species in shallow, warm-water meadows stretching from East Africa and the Red Sea through South and Southeast Asia to Australia and the western Pacific islands. Australia holds the largest remaining population, with the waters of Shark Bay, Queensland, and the Torres Strait supporting concentrations that are significant on a global scale.

Because dugongs consume seagrass in large quantities and disturb the sediment as they feed, they act as engineers of the meadows they depend on, promoting the growth of younger, more nutritious shoots and influencing the structure of the broader benthic community. The IUCN Red List classifies the species as Vulnerable, with populations declining across much of the range due to habitat loss from coastal development and water quality degradation, bycatch in gillnets and shark nets, boat strikes, and the accelerating destruction of seagrass beds linked to climate-driven marine heatwaves and cyclones. Dugongs reproduce slowly, with females typically giving birth to a single calf no more than once every three to seven years, meaning local populations recover poorly from even modest increases in adult mortality.