Investigation of fish resources in fresh water and estuary of Dongguan City

Based on field investigation and sample collecting, we observed the fish resourcesin Dongguan from November 2005 to July 2009. Ninety-eight fish species were collected, belonging to 14 families 34 orders. Three orders and 43 species of Cyprinforms account for 43.88% of the total; Perciformes and Siluriformes account for 27.55% and 9.18% of the total, respectively. The estuary fishes of Culterinae, Leuciscinae, Siluridae and Bagridae mainly distribute in Dongjiang River; the current-favorite fishes of Homalopteridae, Cobitidae, Gobioninae and Labeoninae mainly distribute in the rivulets in the east and southeast of Dongguan; the blackish and fresh water fishes, including Lateolabrax japonicus, Coilia grayi, C.mystus and Clupanodon thrissa, mainly distribute from Pear River estuary to Shilong of Dongguan. Moreover, we find a decline in the fish resources in Dongguan, reflectingin the decrease in the number of valuable special fishes and in the size of fishes. Finally, we discuss the reasons for the resource recession and put forward the strategies for sustainable protection of fish in Dongguan.