Distribution and movement of Chinese sturgeon, Acipenser sinensis, on the spawning ground located below the Gezhouba Dam during spawning seasons

Abstract

Sonic tracking of 40 adult pre-spawning Chinese sturgeons (35 females, 5 males) was done during 8 spawning seasons (1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004). Fish spent most of the time close to the dam (within 7 km). A yearly mean of 64% of the tracking locations of pre-spawners were in the small area of 1.08 km distance below the dam (cell I-B of the tracking grid system). These movements indicate fish continue to attempt to move farther upstream to pass the dam. Adults did not visit areas without major water spills or flow, i.e., the boat canal (the Sanjiang River), the spill gates, and 1# ship lock. Adults were not tracked in the fast current tail waters of the Erjiang power plant and rarely in the Yichang port, although their occurrence ranged from 4 km to 10 km downstream of the dam while also occuring in the channel. Pre-spawning Chinese sturgeon use the Yichang reach in a non-random manner while seeking certain habitats and avoiding others. Adults arrived on the "spawning ground" one day before spawning. Adults move quickly about the spawning ground. After spawning, females quickly moved downstream, whereas males remained for 12-21 days. During a spawning season, females moved less than males.

Applying instream flow incremental method for the spawning habitat protection of Chinese sturgeon (Acipenser sinensis)

“…One of the results for daily flow and daily SHA time series in 2004 is shown in Figure 9. From the results, we find that when the flow decreases from October to November, while the SHA increases by a large amount, which essentially agrees with the investigation that the Chinese sturgeon would mostly spawn during the receding flow period in November (Yang et al, 2006). The annual SHA from 1996 to 2006 in spawning period (Figure 10) can be compared to the surveyed amount of spawned eggs in a normalization form.…”

“…However, after the damming of the Yangtze River by the GD in YiChang (YC) on January 1981, their spawning areas were limited to a 30 km reach below the Dam (Hu et al, 1992) with only two favourable sites remaining, upstream and downstream spawn sites (Figure 1b). In this study, a 7 km segment below the GD was surveyed, which essentially covers the two present spawning sites of Chinese sturgeon (Yang et al, 2006).…”

Species identification of Chinese sturgeon using acoustic descriptors and ascertaining their spatial distribution in the spawning ground of Gezhouba Dam

“…The existing studies had used ultrasonic telemetry to track individual Chinese sturgeon movements and locate the spawning area of Chinese sturgeon [3,32] , but such methodology cannot reveal their spatial distribution. In the present study, we revealed the fish distribution after the precise signals of Chinese sturgeon were obtained.…”

River Temperature Variations and Potential Effects on Fish in a Typical Yangtze River Reach: Implications for Management

“…The temperature regimes at the Yichang Hydrological Monitoring Station were taken as the temperature reference points in the flow regimes that FMCC and Chinese sturgeon were exposed to. However, the fishes may have been some distance from the monitoring station (Yang et al, 2006;, and, therefore, the temperature regime the fishes were actually exposed to may have differed somewhat from that measured at the station. The potential effect of very small differences has been ignored in this study because the water temperatures in that particular reach of the Yangtze main stem are usually very stable.…”