Synopsis:  The Indo-Pacific humpback dolphin (Sousa chinensis) is listed as species under first-class of national protection in China and as Near Threaten in the IUCN Red List of Threatened Species. The population inhabiting the Pearl River Estuary (PRE) is thought to be the world’s largest. So far, however, the dolphin’s pattern of habitat use and the extent of human impacts on this population remain insufficiently known, especially for the dolphins in the western reaches of the PRE. In my study, I analysed data collected during regular boat-surveys conducted in the western PRE over a 5-year period.  I aimed at providing vital ecological information such as: (i) the pattern of distribution and habitat use of humpback dolphins in western PRE; (ii) the prevalence of skin disorders and physical traumas among humpback dolphins in waters of western PRE; and (iii) the pattern and likely causes of stranding across the PRE, including Hong Kong waters.  My findings provide valuable new information about this well-publicised yet still surprisingly little known dolphin population.