Length-weight relationships of six fish species from the Zengqu River and the Ouqu River, southwest China

Abstract

This study provides the first report of length-weight relationships (LWRs) for six endemic fish species collected from the Zengqu River and the Ouqu River, two of the tributaries to the upper reaches of the Jinsha River, southwest China. Samples were obtained in May 2013 and September 2013 using various types of fishing gear. A total of 413 specimens belonging to six fish species were analyzed; their LWRs were W = 0.0069L 3.086 (r 2 = 0.987) for Schizothorax wangchiachii (Fang, 1936), W = 0.0076L 3.029 (r 2 = 0.980) for Schizothorax dolichonema (Herzenstein, 1889), W = 0.0029L 3.315 (r 2 = 0.961) for Schizopygopsis malacanthus (Herzenstein, 1891), W = 0.0082L 2.970 (r 2 = 0.950) for Ptychobarbus kaznakovi (Nikolsky, 1903), W = 0.0017L 3.464 (r 2 = 0.957) for Triplophysa stolioczkae (Steindachner, 1866), and W = 0.0037L 3.190 (r 2 = 0.956) for Triplophysa orientalis (Herzenstein, 1888). Prior to this study, the LWRs for S. dolichonema, P. kaznakovi and T. orientalis were unknown. In addition, new maximum sizes for four of the species are provided.

Length-weight relationships of four fish species from the Yellow River, China

“…For a comparison of b values calculated in our study with 95% confidence limits of Bayesian estimation reported in FishBase (Froese & Pauly, ), the fish species were divided into two groups: (a) one specie with b values within the Bayesian's confidence intervals ( T. siluroides ); (b) three species with both values of the intervals ( S. anteroventris , S. lissolabiatus and T. markehenensis ). Differences in the LWR can be attributed to several factors: a number of factors such as environmental (seasonal variation, habitat type, geographic region) and biological (population, gonadal maturity, sex, growth phase, diet, degree of stomach fullness, health and general fish condition) (Xia, Chen, & Xiong, ; Zhang, Wang, & Liu, ; Zhu, Yang, Liu, & Li, ); however, these factors were not considered in the present study. In addition, the narrow sample size and/or the length range of T. markehenensis possibly affected the b values in the study.…”

“…For a comparison of b values calculated in our study with 95% confidence limits of Bayesian estimation reported in FishBase (Froese & Pauly, 2017), the fish species were : coefficient of correlation. Xiong, 2016;Zhang, Wang, & Liu, 2017;Zhu, Yang, Liu, & Li, 2015); however, these factors were not considered in the present study.…”

Length-weight relationships of three small fish species caught in the Yarlung Zangbo River basin, China

“…The b value (2.986) in G. maculatum estimated by the present study is lower than b values (female = 3.142, male = 3.147) of G. maculatum from the Nianchu, Lhasa and Nyang Rivers (Li & Xie, ). Differences in the LWR can be attributed to several factors such as area, gonad maturity, diet, stomach fullness, health, age, fishing time (seasonal and annual fluctuations; Zhu, Yang, Liu, & Li, ). Among them, one more important reason attributed to the LTR estimates vary is methodology effects (net selectivity).…”

Length-weight relationships for four species in the Dogxung Zangbo River, a main tributary of the Yarlung TsangpoRiver, Tibet, China

“…These rivers have highly endemic fishes, which is not well investigated. Length‐weight relationships (LWRs) are important in field studies that are limited by resources and time (Xiong et al., ; Zhu, Yang, Liu, & Li, ), essential to estimate growth rates, length and age structures, and other components of fish population dynamics (Kolher, Casey, & Turner, ), and useful for monitoring the state of health of a population (Cone, ). The aim of this study was to analyse length‐weight relations for the species living in the Dogxung Zangbo River and the upper reaches of the Yarlung Tsangpo River.…”