the indo-pacific humpback dolphins were first discovered along the west coast of taiwan in 2002. based on a survey done in 2002 and 2003, they are often found in waters <5m deep, and no evidence shows that they appear in water deeper than 15m. a study in 2008 found that the population of humpback dolphins, which occupies a linear range of about 500 km^2 along the central west coast of taiwan, is genetically distinct from all populations living in other areas. and this population is called eastern taiwan strait (ets) population.