Humpback dolphins (genus Sousa), obligatory inshore delphinids, are frequently exposed to adverse effects of many human activities. In Hong Kong, one of the world's most urbanised coastal regions, ~ 50% of the dolphins suffer from at least one type of epidermal lesions, likely related to anthropogenically degraded habitat. Furthermore, one in every ten dolphins has physical injuries indicative of vessel collisions, propeller cuts and fishing-gear entanglements. As top predators with long lifespan, dolphins are good "barometers" of marine environment and their compromised health conditions are symptomatic of increasingly degraded ecological conditions of coastal seas, especially in rapidly developing regions of fast-growing economies.
Keywords: Anthropogenic pressure; Ecological health indicators; Hong Kong–Pearl River Estuary; Indo-Pacific humpback dolphin Sousa chinensis; Physical injuries; Skin lesions.