Dugongs (Dugong dugon) are the sole extant species in the family Dugongidae in the aquatic mammalian order Sirenia. The species is widely distributed in tropical and sub-tropical Indian Ocean and western Pacific Ocean, occurring in coastal waters of 48 countries range-wide. Currently the IUCN Red List status is Vulnerable, however the true status throughout much of the range is unknown and many or most populations are thought to be threatened due to overexploitation. At least two regional populations are thought to be extinct, in Mauritius and Taiwan, China.
Most current information on dugongs in coastal waters of Madagascar is based on unpublished reports and anecdotal communications and their current population status is uncertain. They are known to occur throughout Madagascar but are believed to be heavily exploited; sightings of live animals are very rare.
Historically, there are reported sightings and captures from the north, northwest, central west, southwest and northeast regions, indicating important habitat in the Masoala Peninsula/Antongil Bay in the northeast, and Ampasindava in the extreme north; the Bay of St. Augustine in the southwest, and around Soalala and the Nosy Be region in the northwest were previously important areas but no longer, suggesting local extirpation in portions of their original range. Populations appeared to have declined rapidly since the 1980s, with generally sparse populations.
There are very few observations of live animals in any completed studies, however aerial surveys for marine megafauna recently documented several live sightings along the northwest coast between Mahajanga and Bay of Sahamalaza. WCS has accumulated evidence and reports on the distribution and status of dugongs along an extended length of the west coast of Madagascar, based upon socio-ecological interview surveys with local fishers. Dugongs were reported geographically widespread from the northwest to southwest, with the highest numbers among our sampled locations reported in the southwest locations of Bevato and Andavadoake, the mid-west location of the Barren Islands, and the northwest location of Nosy Mitsio (Ankarea MPA) and the Ampasindava peninsula (Ankivonjy MPA).
There is evidence for a decline in numbers of sightings and individuals captured in hunting and by-catch during the most recent decade (2000-2010), and shifts in the relative distribution of reports over time, suggesting that populations may be more impacted or near extirpated in some locations.