Growth and mortality of topmouth gudgeon Pseudorasbora parva and evaluation on resource utilization in Taihu Lake
LIU Kai，JING Li，CHEN Yong-jin，XU Dong-po
Scientific Observing and Experimental Station of Fishery Resources and Environment in the Lower Reaches of Yangtze River，Ministry of Agriculture，Freshwater Fisheries Research Center，Chinese Academy of Fishery Sciences，Wuxi 214081，China
Abstract: Based on a total of 1207 samples of topmouth gudgeon Pseudorasbora parva collected by shrimp pot from January to December in 2014，an investigation was conducted monthly in Taihu Lake to study the composition，growth and mortality of capture as well as the resources utilization.The standard body length of samples ranged from 27.03 mm to 107.36 mm with mean value of（60.03±13.29）mm while the body weight ranged from 0.4 g to 21.2 g with the mean value of（4.51±3.16）g.A power function was presented between the body length and body weight while the relationship exhibited as follows：W=2.1606×10-5L2.9537（R2=0.9323，n=1207）.The parameters of Von Bertalanffy growth equation were displayed as below：L∞=112.88 mm，K=0.46，t0=-0.51 a.The inflection point of body weight was about 1.84 years.Total mortality coefficient（Z）was 1.87 estimated by transformed body length catch curve method and natural mortality coefficient（M）was estimated about 1.07 with Pauly equation.Fishing mortality coefficient（F）was 0.80 and exploitation rate（E）was 0.43.The results showed that topmouth gudgeon confronting lower fishing pressure in Taihu Lake，stayed in a moderate utilization state which was related to non-targeted fishing and the enactment of forbidden fishing period in Taihu Lake，and the meanwhile，fishing pressure that carnivorous fishes faced in fishing period was beneficial to the proliferation of small-sized fish species as well.
2016, Vol. 31 
