The July 2003 report says since January 2000, only 32 sightings of this once abundant sea mammal were recorded. Of these, only eight were of live animals at sea. The rest, 75 per cent, were dead having been entrapped and entangled in gillnets. "It is clear that dugongs are now critically endangered in Tanzania, and without immediate concerted conservation effort, they will almost certainly become nationally extinct in the near future," the report warns.
Dugongs, also called sea cows, are herbivorous mammals that live in shallow sheltered waters. They are descendants of terrestrial swamp browsers that lived about 55 million years ago. Their closest living relative is the elephant. Dugongs grow to 3.5m in length and to 400kg in adulthood, and live to about 70 years.

Dugongs were historically a prized source of protein and oil, which was used for cooking, waterproofing boats, and occassionally for treating a variety of ailments along the eastern Africa coast. They are believed to be the most endangered large mammal in Africa, with growing concern that they are faced with extinction in eastern Africa.
Tanzania's dugong population is estimated to be less than 100 individuals, a level so low that scientists doubt they can recover. In the 1960s, herds of 20 to 30 dugongs were frequently sighted along the Tanzanian coast, gillnet fishermen reporting capturing up to five dugongs in any given day. The situation has since changed dramatically. From the year 2000, eight to ten dugongs are captured every year in Tanzania.