Species-specific variations in reproductive traits of three yellow catfish species (<i>Pelteobagrus</i> spp.) in relation to habitats in the Three Gorges Reservoir, China

<div><p>The reproductive biology of three yellow catfish congeners was studied in the Three Gorges Reservoir of the Yangtze River, China. We compared reproductive traits among the lentic, transitional, and lotic zones. A total of 4502 individuals of the three species was collected, and the sex ratio, size at 50% maturity, spawning season, fecundity, and egg size were determined. Results showed that populations inhabiting the lotic zone spawned earlier than those inhabiting the lentic zone. For the three species, fecundities were significantly higher for populations in the lotic zone than for those in the lentic and transitional zones (<i>P</i> < 0.05). <i>Pelteobagrus vachelli</i> (Richardson) and <i>P</i>. <i>fulvidraco</i> (Richardson) displayed an obvious trade-off between egg size and fecundity, whereas <i>P</i>. <i>nitidus</i> (Sauvage <i>et</i> Dabry) produced the largest eggs in the lotic zone. Sex ratios were significantly different among zones (<i>P</i> < 0.05, for each species), but the bias patterns were different. Sizes at 50% maturity of female <i>P</i>. <i>nitidus</i> and <i>P</i>. <i>vachelli</i> were the largest in the lotic zone and the smallest in the transitional zone, but was similar among zones for <i>P</i>. <i>fulvidraco</i>. Overall results suggest that the three yellow catfish species developed different reproductive traits among the three habitats in the TGR, whereas the variations reflected further interspecific differences. Our study indicates the importance of riverine habitats for the conservation of species of fish, even for species such as these eurytopic catfish inhabiting the upper reach of the Yangtze River. This study further suggests that species-specific responses should be considered when evaluating the influences of new hydropower projects, even for such closely related species of fish.</p></div

Relevant details of numbers (N) of the three yellow catfish species sampled and their mean total length (TL) (mm) and mean body weight (BW) (g) in the lotic, transitional, and lentic zones of the Three Gorges Reservoir.

<p>Relevant details of numbers (N) of the three yellow catfish species sampled and their mean total length (TL) (mm) and mean body weight (BW) (g) in the lotic, transitional, and lentic zones of the Three Gorges Reservoir.</p

Monthly changes in water temperatures (°C) (mean ± S.E.) and water levels (m) in the Three Gorges Reservoir.

<p>Data were collected from August 2014 to July 2015.</p

Map of study area along the Three Gorges Reservoir, upper reaches of the Yangtze River.

<p>Small solid rectangular shows the location of the Three Gorges Dam. Solid triangles represent the lentic (Zigui), transitional (Wanzhou), and lotic zones (Mudong) of the Three Gorges Reservoir.</p

Summary findings on reproductive traits of populations of the three yellow catfish species in the lotic, transitional, and lentic zones of the Three Gorges Reservoir.

<p>Summary findings on reproductive traits of populations of the three yellow catfish species in the lotic, transitional, and lentic zones of the Three Gorges Reservoir.</p

Monthly changes of gonado-somatic indexes (GSI) (mean ± S.E.) of females.

<p>Data were collected from August 2014 to October 2015.</p

Growth performance of different icefish populations in Lake Erhai.

<p>Month by month (6/2010-5/2011) comparisons by lake section of mean (A) total length (B) body weight, and (C) condition factors of icefish in Lake.Erhai. Data are presented as mean±1 SE.</p

Traditional fishery model and ecosystem-based fishery model in Yangtze lake.

<p>Traditional fishery model and ecosystem-based fishery model in Yangtze lake.</p

Water quality parameters of Wuhu Lake (China) before and after the start of bio-manipulation in 2008.

<p>Water quality parameters of Wuhu Lake (China) before and after the start of bio-manipulation in 2008.</p

Mean water parameters and standard error pre (2006–2007) and post bio-manipulation (2008–2011) of Lake Wuhu.

<p>Statistical test (t = t-test; MWW = Mann-Whitney-Wilcoxon test), significance (<i>P</i>) and degree of freedom (df) are included.</p><p>Mean water parameters and standard error pre (2006–2007) and post bio-manipulation (2008–2011) of Lake Wuhu.</p