The Indo-Pacific humpback dolphin has a typically streamlined body and a long slender beak (5). Populations differ in both shape and colour, with those in the west of the range possessing a 'double-step' dorsal fin with a fatty hump upon which the dorsal fin sits (6). Although usually dark grey on their back and lighter underneath, white and pink variations are also known; the most famous of these are the 'pink dolphins' of Hong Kong bay (2). The humpback dolphin has an unusual diving posture, first lifting its beak out of the water and arching its back, and then pausing before dipping below the surface or flipping its tail to dive (2). Given the wide morphological differences, there is some disagreement as to whether the Indo-Pacific humpback dolphin does in fact represent four different species: Sousa plumbea, Sousa lentiginosa, Sousa chinensis and Sousaborneensis respectively (5).