It is a slow-moving heavy herbivore with a nose shaped like a vacuum cleaner. It feeds exclusively on a variety of seagrasses primarily found in shallower inshore waters. A decade ago Australia was believed to have the largest, most stable dugong populations left in the world. This situation is rapidly changing. Elsewhere in the world scientists believe the dugong is doomed.
Gill netting is believed to be the single greatest threat.
Nets targeting fish species such as mackerel are set in dugong habitat and the dugong, which have poor vision, become entangled and drown in the nets. Net fishers frequently dispose of the body by eviscerating the buoyant intestines and tying the dead dugong to the submerged roots of mangroves in an effort to prevent its floating to the surface and being discovered. This mortality is believed to be continuing at a rate between 6 and 10 percent, which is clearly unsustainable. In 1997 at least 23 dugong killed by nets washed up on beaches of north Queensland in a two month period. 11 dugong died during one month, September, in 1998.