Study On The Growth And Spatial Distribution Of Pacific Saury (Cololabis Saira) Based On Otolith Information

It is one of the main pelagic fishing species,as one of the important fishery resources of China in the northwest Pacific Ocean.At present,there are few researches on the age,growth,otolith microstructure and other contents,and there is no analysis on the characteristics in different Spaces,which is helpful for China to understand the age structure,spatial characteristics and life history characteristics of saury.According to the July to November 2015 fishing saury samples,for the group composition of northwest Pacific saury,otolith measurement data and the growth of the spatial analysis,to explore of biological characteristics under different space,the otolith grinding microstructure and researched,It will lay a foundation for the future research on the life history of saury.The main conclusions of this study are as follows:(1)Besides?are distributed in male body length,body weight frequency single type,the rest are in double types or kinds of distribution,the sea area is saury habitat groups mixed phenomenon of saury.?and?,?and?the relationship between body length and weight exists significant difference(P<0.05);?,?,??the relationship between body length and weight power parameter b:3.1,2.8,3.27 and 3.09,respectively.(2)the average number of otolith incubation rounds was 4.98±0.136,and the average diameter of otolith incubation core was 60.8±0.899um.There are seven types of marking wheels in the core area,dark area and transparent area of the otolith grinding pieces of saury,and there are irregular otolith structure(sub-core,dense body of otolith core,etc.)and sub-solar wheel grain structure.The width of otolith wheel grain generally shows a downward trend,In the same time and population,the trend of the width of the wheel of the fish was correlated locally.(3)there was no significant difference in the measurement parameters of left and right otolith of saury(P>0.05).?,?and?between male and female individual otolith measurement parameters have no significant difference(p>0.05),?area otolith weight(M)between male and female(p<0.05),otolith circumference(Pe)(p<0.05),rostrum length(OC)(p<0.05)and the otolith length(ab)(p<0.05)significant differences.The body length of female saury was in a power function relation with OC and ab,while the body length of female and male saury was in an exponential function relation with M and Pe.The relationship between body length and OC and ab was exponential.(4)?,?,?and?area saury length and M,Ar,Pe,OF,OR,ab and bc there were significant correlation(P<0.01),and have been power function relationship.From September to November,OA gradually decreases,and the sea on the west side is less than on the east side of OA.(5)the age range of saury is 183?559d.Among them,there were 113 male samples,with a range of age ranging from 192 to 554d,with a maximum body length of 293mm and weight of 138g.The minimum age was 227mm and the weight was 75g.There were183 female samples,the range of age was 193?559d,the maximum length of 304mm and the weight was 130g.The minimum age length was 215mm and 62g in weight.(6)?,?,?and?area there is a difference of age structure.There were no significant differences in age and body length,age and body weight between males and females and between Marine areas(P>0.05).Based on linear,exponential,logarithm,power function,Gompertz,Logistic and Von Bertalanffy growth models,body length and body weight growth were suitable for Logistic growth model,and the maximum progressive body length(TC_?)was 300.83mm.The maximum progressive weight(TZ_?)was 137.03g.The growth equation is as follows:(?)The body length growth rate of saury decreased with the increase of age,and the average growth rate was 0.4mm/d.The growth rate of body weight increased with the growth of day age,with an average growth rate of 0.24 g/d.(7)there was no significant difference in the relationship between age and M between male and female(P>0.05).The relationship between age and M in?and?,?and?between the significant difference(P<0.05).?,?,??sea area and the relationship between age and M respectively suitable for logarithmic function,power function,logarithmic function and Logistic equation.The absolute growth rate of M increased with the growth of day age,and reached the maximum of 0.0029mg/d at day age of 230-272d,and the minimum of 0.0008mg/d at day age of 376-423d.The absolute average growth rate of M is 0.0018mg/d.(8)there was no significant between sex in age and Ar,Pe,ab and bc(P>0.05).Age with Ar,Pe and ab in?and?,?and?is significant(P<0.05),and age with bc significant of?and?(P<0.05).The relationship between daily age and Ar,Pe,ab and bc is logarithmic.Ar,Pe,ab and bc increase with age.The average absolute growth rates of Ar,Pe,ab and bc were 0.0031mm~2/d,0.0059mm/d,0.002mm/d and 0.0013mm/d,respectively.