Abstract: This study was performed to determine the spatial structure and bottom characteristics of the only remaining spawning area of Chinese sturgeon (Acipenser sinensis) located just downstream of the Gezhouba Dam. During the period 1996–2003, three methods were employed, including (i) the examination of the stomachs of opportunistic predatory fishes that feed on sturgeon eggs, (ii) tracking the mature sturgeons by ultrasonic tags and (iii) capturing eggs and yolk-sac larvae(ELS) at and near the river bottom by D-shaped bottom drift nets to monitor the spawning activities of A. sinensis. It was found that A. sinensis selected permanent locations to mate. There were two mating locations: an upstream mating area(UMA), in the tailrace of the Dajiang Hydroelectric Station and about 870 m far from the Gezhouba Dam (area, 0.1 km2), and a downstream mating area (DMA), about 2500 m from Gezhouba Dam (area, 0.3 km2). The DMA was the chief mating area and was used every year. The incubation area (for dispersal of fertilized eggs to incubate) was range from 870m to 7 km from the dam. Generally, the total length of the spawning area was 5–7 km length (area 2.0–2.7 km2) with the range slightly varied in different spawning activities. A relief map of the riverbed and a bottom hydroacoustic survey of the DMA found a deep depression and rocky substrate. These may be important characteristics of geomorphology for the spawning area of A. sinensis.


附件下載：H.Zhang, Q.W.Wei, B.E.Kyanrd, et al. Spatial structure and bottom characteristics of the only remaining spawning area of Chinese sturgeon in the Yangtze River.J.Appl.Ichthyol. 2011,27: 251-256. pdf