Delphine Chabanne

The Australian snubfin dolphin (Orcaella heinsohni, ‘snubfin dolphin’ hereafter) and Australian humpback dolphin (Sousa sahulensis, ‘humpback dolphin’ hereafter) are poorly understood species of dolphin whose global distribution is restricted to shallow coastal and estuarine waters of northern Australia and southern New Guinea.

Here, we investigate the population genetic structure and relative abundance of these two species at selected study sites in the Kimberley region of north-western Australia. Additionally, we investigate the application of passive acoustic monitoring (PAM) as an effective technique for monitoring these species in the remote waters of the Kimberley region, with potential applications across northern Australia.

An investigation into the deaths of six Indo-Pacific bottlenose dolphins (Tursiops aduncus) within the Swan Canning Riverpark between May-October 2009 found that a suite of factors likely contributed to the mortalities (Beazley 2010; Holyoake et al. 2010). This investigation, along with research undertaken for Swan Canning Research Innovation Program (SCRIP) Project: ―Toxicant exposure, population genetics, and trophic associations of bottlenose dolphins (Tursiops sp.) in the Swan River‖ (Holyoake et al. 2011), emphasised the vulnerability of the resident community to natural and anthropogenic stressors and the need to improve the scientific basis for the long-term conservation of dolphins within the estuary. To support this aim, the Swan River Trust and Murdoch University entered into a collaborative agreement Project to undertake further health and ecology investigations into dolphins in the Swan Canning Riverpark and to conclude analyses of existing data and samples. This report presents the major findings for this project.