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Quinn JTII, Deriso RB (1999) Quantitative fish dynamics. Lagler KF (1972) Freshwater fishery biology. These data corroborate that a combination of natural and anthropogenic factors has caused a sharp decline in wild populations during recent years, calling for immediate design and implementation of conservation measures for this species.Įrdoğan O, Türkmen M, Yildirim A (2002) Studies on the age, growth and reproduction characteristics of the chub, Leuciscus cephalus orientalis, (Nordmann, 1840) in Karasu River, Turkey. Standard length and age of 86.5 % individuals were below 25 cm and 4 years, respectively, indicating that the exploitation is too intensive and that populations are undergoing miniaturization. Female gonad analysis suggests that rock carp is a batch spawner, which can spawn at least twice during the reproductive season, from April to August. The estimated length at 50 % sexual maturity for males is 24.2 cm (approximately aged 4) and 37.0 cm for females. The von Bertalanffy growth curves computed by the observed length-at-age data could be expressed as L t = 64.9(1 − e −0.101( t+0.217)). The results indicate that there are no significant differences between the length–weight relationships of females and males ( W = 0.015SL 3.155). In the present study, with the aim to give suggestions for better conservation, we investigated age, growth, and reproductive biology of the rock carp using samples collected between 20 from the Chishui River. Its populations have dramatically declined in the recent years due to human activities, such as overfishing and damming. Rock carp is an endemic fish in the upper Yangtze River basin.
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