Growth performance of Amur pike(Esox reicherti Dybowski) in the upper reaches of Wusuli River

The growth performance of Amur pike(Esox reicherti Dybowski) Wusuli River was studied on the base of 840 specimens collected from the upper reaches of boundary Wusuli River between China and Russia in 2003.The pike samples were almost younger than 6~+ years old in the upper reaches of Wusuli River,and the fish younger than 3~+ years old accounted for 74.52% of the captured population. Biostatistics analysis showed that the relationship between body length,L(cm),and body weight,W(g) may be expressed as W=0.0051L~(3.1023)(r=0.9762),indicating that it is characterized by isometric growth.The von Bertalantty equations for the fish were as follows: L_(t)= 120.17[1-e~(-0.1215(t+0.5983))], W_(t)=15139.22 [1-e~(-0.1215(t+0.5983))]~(3.1023),the growth rate curves are dL/dt=14.60e~(-0.1215(t+0.5983)), dW/dt=5518.2e~(-0.1215(t+0.5983))[1-e~(-0.1215(t+0.5983)]~(2.1123),and the acceleration trend can be characterized by d~2L/dt~2=-1.7740e~(-0.1215(t+0.5983)), d~2W/dt~2=5518.2e~(-0.1215(t+0.5983))[1-e~(-0.1215(t+0.5983))]~(1.1123)[3.1123e~(-0.1215(t+0.5983))-1].The growth inflection point of body weight was at t=8.7 years,corresponding to W=4531.7 g.The results indicated that some measures should be taken to protect the individuals aging of 4-8 from overfishing in the upper reaches of Wusuli River and protect the fish resources rationally.