It was believed that the historical spawning grounds of the anadromous Chinese Sturgeon (Acipenser sinensis) were located along an about 600 km long river section reaching from the lower reaches of the Jinshajiang River to the upper reaches of the Yangtze Rive.

As a result of the construction of the Gezhouba Hydroelectric Dam was built in 1981, the upstream spawning migration route was blocked by the Dam. Successful natural reproduction, however, has been observed in small areas below the dam since 1982. Some biologists held that there was a certain relationship between the spawning of Chinese sturgeon (CS) and the hydrology as well as the substrate types of the river bottom. In total, spawning runs of the CS were observed 37 times between 1983 and 2004. Five hydrological factors (water temperature, water level, flow discharge, silt content and current velocity) were monitored on a daily basis at the spawning ground between October and November for 22 years (1983 to 2004). The current velocity on the spawning ground at the river bottom was measured while CS were spawning during 4 years (1996 to 1999). The authors analyzed the relationship between five hydrological factors and the respective spawning runs. The results showed that mean current velocity during October and November and the resulting mean silt content in the sediment in November in the reach of spawning ground were significant differences (P<0001) from those immediately after the construction of the Gezhouba Dam. However, monthly mean water level, flow discharge and water temperature had no obvious effects on the bottom conditions. The 22-years of observations indicate that the daily mean values of all of the 5 hydrological factors fluctuated within a certain range while CS were spawning. It is concluded that the optimal values for the hydrological factors during the spawning run are 18.0 to 20.0℃ for temperature, 14100 m³/s discharge volume, a water level of 42.0 to 45.0m above sea level, and a silt content in the water of 0.2 to 03 kg/m³ while the current speed above the bottom to stimulate the fish to spawn should be between 1.0 to 1.7m/s. The optimal water temperature might provide an essential pre-condition for the other factors becoming a valid trigger for spawning. As water temperature arrive approaches the optimal values and most of the other parameters are at the brink to deviate from their optimal range values (water level, current velocity, silt content in the water), CS would begin to spawn. By 2009, when the Yangtze Three Gorges Project, which is located 45 km upstream the Gezhouba Dam, is completed and begins to operate normally, changes in the downstream water temperature are expected and these may have a negative effect on the gonad development and the stimulation of spawning of CS, however, the anticipated decline of silt content in the water may be considered as favourable for the performance of the spawning site.