A future for the dugong

The dugong (Dugong dugon) is the only herbivorous mammal that is strictly marine and is the only extant species in the Family Dugongidac. The other members of the order Sirenia, the three species of manatee, all use fresh water to varying degrees (Reynolds and Odell 1991). The only other recent Sirenian, Steller's sea cow, Hydrodamalis gigas, was hunted to extinction within 27 years of its discovery in the eighteenth century (Stejneger 1887). All extant members of Order Sirenia (induding the dugong) are listed as vulnerable to extinction (Hilton-Taylor 2000). All populations of the dugong are also listed on Appendix 1 of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Prospects for the survival of the dugong are the best among the Sirenia, because each manatee species has a more localised distribution than that of the dugong (Reynolds and Odell 1991). In addition, the estimates of dugong abundance in Australia which total to a mean of about 85000 individuals (Marsh et al. 1999) are much greater than have been recorded or suggested for any species of manatee.