The world's second largest population of humpback dolphins in the waters of Zhanjiang deserves the highest conservation priority.

Chinese white dolphins (Sousa chinensis) inhabiting shallow coastal waters are vulnerable to impacts from human activities in the near shore waters. This study examined the population of Chinese white dolphins occurring off the coast of Zhanjiang in the northern South China Sea. A total of 492 Chinese white dolphins were identified, 176 of which were photographed on more than one occasion. The Zhanjiang Chinese white dolphin population is isolated from populations of conspecifics along the Guangdong coast. It is composed of approximately 1485 individuals (95% CI = 1371-1629; SE = 63.8), with estimates of mean representative range and core area of 168.51 and 44.26 km(2), respectively. The high site fidelity and long-term residence of Chinese white dolphins in the study area are well established. A review of all available data indicates that based on what is currently known, the Zhanjiang Chinese white dolphin population is the second largest of the species and genus in the world. However, the recent industrial boom along the Zhanjiang coast has increased concerns regarding the conservation of the Zhanjiang Chinese white dolphin population. We recommend the designation of a national nature reserve as a most urgent measure for protecting Chinese white dolphins in Zhanjiang waters.