Dugong (Dugong dugon) feeding on seagrass. This aquatic mammal is found in groups throughout shallow waters of the South Pacific and Indian oceans. It is related to the manatee but is smaller, reaching a length of less than 3 metres. Also known as sea cows, dugongs are herbivores that graze on seagrasses. They can live for up to 70 years. Photographed in the Red Sea, off Egypt.