Reservoir impoundment changes original fluvial habitats into lentic environments. Fish species adapted to lentic habitats may take the advantage of such habitat changes and show typical life history traits might facil...Reservoir impoundment changes original fluvial habitats into lentic environments. Fish species adapted to lentic habitats may take the advantage of such habitat changes and show typical life history traits might facilitate the population increase. Siniperca kneri rarely occurred in fishery landing in the Three Gorges Reservoir (TGR) area before its impoundment in 2003, but it is now a dominant species. In this study, a total of 438 females of S . kneri were collected monthly during September 2012 through January 2014 using gill nets in the TGR. The age, growth, and reproductive biology were then investigated, and compared with other S . kneri populations. The standard length at age 1 was 149.9 mm in the TGR, which is larger than the three compared populations (i.e., Sandaohe Reservoir, Xinfengjiang Reservoir, and North River), but smaller than one (the Guishi Reservoir). The youngest mature female in the TGR was age 1, which is younger than that of the two compared populations (i.e., Xinfengjiang Reservoir and the North River). The relative fecundity in the TGR was 140 eggs/g, which is higher than that of the only available compared population (Xinfengjiang Reservoir, 96 eggs/g). Our results demonstrated that S . kneri in the TGR tended to have faster growth in the first year, a younger age at first maturation, and higher reproductive eff ort. We suggest that such opportunistic-tended life history traits might facilitate rapid increase of the population.展开更多
Most of the closely related fish species are similar in appearance,with slight differences.This study evaluated 35 morphological characteristic parameters and the number,shape,and spatial location of bones in the skul...Most of the closely related fish species are similar in appearance,with slight differences.This study evaluated 35 morphological characteristic parameters and the number,shape,and spatial location of bones in the skull and vertebrae of the mandarin fish Siniperca chuatsi and big-eye mandarin fish Siniperca kneri.We can understand their ecological adaptability,compare their morphological and skeletal differences,and elucidate the relationship between their phenotypic trait differences and skeletal characteristics.The results were as follows:1.The Student’s t-test results revealed significant differences between S.chuatsi and S.kneri in terms of head depth,head back length,snout length,interorbital distance,distance of the eyes from the oral fissure,and width between the posterior trunk and base of the caudal fin.Principal component and discriminant analysis showed that the main morphological differences between S.chuatsi and S.kneri were in the eye position,head hump and body shape.2.There was no significant difference in the number and shape of the skull and vertebrae between S.chuatsi and S.kneri,but they differed in spatial position.The terminus of the maxilla in S.chuatsi is located at the lower border of the postorbital bone,but at the anterior in S.kneri.The size of head hump is closely related to the spatial location of the splanchnocranium in S.chuatsi and S.kneri.The angles between the caudal vertebrae centrum and each of the following:the neural arch and spine;haemal arch and spine of S.chuatsi are larger than those of S.kneri.In conclusion,the morphological differences between S.chuatsi and S.kneri are closely related to the spatial position of skeleton.These phenotypic differences reflect the ecological adaptation of mandarin fish to different natural environments.展开更多
The growth and fecundity of Siniperca chuatsi and Siniperca kneri are investigated.The results show that Siniperca chuatsi grows faster than Siniperca kneri.There are curve regression relationships between the body we...The growth and fecundity of Siniperca chuatsi and Siniperca kneri are investigated.The results show that Siniperca chuatsi grows faster than Siniperca kneri.There are curve regression relationships between the body weight(m) and standard length(L) with relational expressions as follow: m=0 081 L 2.71 and m= 0 076 55 L 2.59. Siniperca chuatsi’s fecundity is bigger than that of Siniperca kneri. Siniperca chuatsi and Sniperca kneri attain maturity at two-winter-age and three-winter-age respectively.In addition,the growth equation,the growth speed and growth acceleration equation of body length and body weight are also studied.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.51209202,31570420)the Science and Technology Research Project of China Three Gorges Corporation(No.CT-12-08-01)the Hubei Key Laboratory of Three Gorges Project for Conservation of Fishes(No.0704101)
文摘Reservoir impoundment changes original fluvial habitats into lentic environments. Fish species adapted to lentic habitats may take the advantage of such habitat changes and show typical life history traits might facilitate the population increase. Siniperca kneri rarely occurred in fishery landing in the Three Gorges Reservoir (TGR) area before its impoundment in 2003, but it is now a dominant species. In this study, a total of 438 females of S . kneri were collected monthly during September 2012 through January 2014 using gill nets in the TGR. The age, growth, and reproductive biology were then investigated, and compared with other S . kneri populations. The standard length at age 1 was 149.9 mm in the TGR, which is larger than the three compared populations (i.e., Sandaohe Reservoir, Xinfengjiang Reservoir, and North River), but smaller than one (the Guishi Reservoir). The youngest mature female in the TGR was age 1, which is younger than that of the two compared populations (i.e., Xinfengjiang Reservoir and the North River). The relative fecundity in the TGR was 140 eggs/g, which is higher than that of the only available compared population (Xinfengjiang Reservoir, 96 eggs/g). Our results demonstrated that S . kneri in the TGR tended to have faster growth in the first year, a younger age at first maturation, and higher reproductive eff ort. We suggest that such opportunistic-tended life history traits might facilitate rapid increase of the population.
基金This study was supported by China Agriculture Research System(CARS-46).
文摘Most of the closely related fish species are similar in appearance,with slight differences.This study evaluated 35 morphological characteristic parameters and the number,shape,and spatial location of bones in the skull and vertebrae of the mandarin fish Siniperca chuatsi and big-eye mandarin fish Siniperca kneri.We can understand their ecological adaptability,compare their morphological and skeletal differences,and elucidate the relationship between their phenotypic trait differences and skeletal characteristics.The results were as follows:1.The Student’s t-test results revealed significant differences between S.chuatsi and S.kneri in terms of head depth,head back length,snout length,interorbital distance,distance of the eyes from the oral fissure,and width between the posterior trunk and base of the caudal fin.Principal component and discriminant analysis showed that the main morphological differences between S.chuatsi and S.kneri were in the eye position,head hump and body shape.2.There was no significant difference in the number and shape of the skull and vertebrae between S.chuatsi and S.kneri,but they differed in spatial position.The terminus of the maxilla in S.chuatsi is located at the lower border of the postorbital bone,but at the anterior in S.kneri.The size of head hump is closely related to the spatial location of the splanchnocranium in S.chuatsi and S.kneri.The angles between the caudal vertebrae centrum and each of the following:the neural arch and spine;haemal arch and spine of S.chuatsi are larger than those of S.kneri.In conclusion,the morphological differences between S.chuatsi and S.kneri are closely related to the spatial position of skeleton.These phenotypic differences reflect the ecological adaptation of mandarin fish to different natural environments.
文摘The growth and fecundity of Siniperca chuatsi and Siniperca kneri are investigated.The results show that Siniperca chuatsi grows faster than Siniperca kneri.There are curve regression relationships between the body weight(m) and standard length(L) with relational expressions as follow: m=0 081 L 2.71 and m= 0 076 55 L 2.59. Siniperca chuatsi’s fecundity is bigger than that of Siniperca kneri. Siniperca chuatsi and Sniperca kneri attain maturity at two-winter-age and three-winter-age respectively.In addition,the growth equation,the growth speed and growth acceleration equation of body length and body weight are also studied.
