In their study, phylogenetic information obtained from a highly repetitive DNA (hrDNA) component characteristic of all cetaceans show that Orcaella share close relationships with the Delphinidae rather than the Monodontidae.
[10] One of their most common habitats are in the Mekong River of southern Laos, Ranging from the Khone Falls all the way to the Cambodian Border.
[11] Much of the data on the Irrawaddy dolphins of this region is collected by the Lao shore, where they are sighted daily during the dry season supposedly due to the importance of deep-water pools in the area.
[12] In the western Gulf of Carpentaria in Australia, an estimate of one thousand specimens were calculated, though this number may be incorrect due to the lack of visibility when looking into the water and the unpredictable movement patterns of the dolphins.
In spite of this, it is difficult to specifically designate a number for their population due to outstanding factors such as the large lack of data and human interference.
[19] In 2008, the IUCN Red List changed its assessment of the Irrawaddy dolphin (Orcaella brevirostris) from data deficient to vulnerable.
They include mortality from bycatch (specifically gillnets); habitat degradation caused by: dams, deforestation, and mining; contact with vessels; and capture for live aquarium display.
[20] Other potential threats include noise pollution in nearby cities and the possibility of mass pathogen induced mortalities.
After more conclusive data is collected, a reassessment of the species has the potential to be categorized as either vulnerable or endangered.
[21] Due to its occurrence in the close proximity to the Australian/New Guinean shore, the Australian snubfin dolphin is threatened by anthropogenic causes.
A significant number of Australian snubfin dolphins are killed by anti-shark nets used to protect bathers and inshore gill-nets embedded across creeks and rivers.
[21] Regulations have been set in order to mitigate bycatch, however net attendance rules and gear modifications are hardly enforced.