Age And Growth Of The North Pacific Albacore(Thunnus Alalunga)

Albacore(Thunnus alalunga)tuna is a kind of highly migratory species that mainly distributed in the Atlantic,Pacific and Indian Ocean.In the north Pacific albacore tuna general in the spring and early summer in the tropical and subtropical waters of the western and central Pacific Ocean spawning.In the infancy of albacore tuna,a certain number of albacore tuna migrate from the land of the north Pacific to the east the temperate waters of the Pacific Ocean.Sexually mature fish will be migrated to the west of the Pacific tropical and subtropical regions to spawn,the pattern will be recorded by young fish.In view of albacore tuna this migration characteristics,for its sustainable development are important basis and economic management.The author was measured 845 Albacore Tuna,and collected the vertebrae and fins samples,on the ultra-low temperature jets fishing vessel "Tianxiang" NO.16 from 2013 to 2014.Using the Ocean University of Shanghai Oceanic Fishery Resources Development Ministry of Education Key Laboratory of Age and Growth Laboratory equipment to analysis vertebrae and fins for age identification,and the effective samples were 209,239,respectively.The linear model,the power function and the exponential function are used to fit the relationship between the length of the fork and the radius of the vertebrae and the fins.Then,the optimal model is used to fit the AIC Akai information criterion.The growth equation of Albacore tuna was obtained by fitting the data.Then,the growth distance,growth rate and growth index were obtained based on the growth equation.The age and growth of the Albacore tuna were studied.The main results were as follows:(1)In this study,four different staining methods were used in the identification of the age.By comparing the effects of four different vertebral bone staining methods on age identification,we obtained 0.5% alizarin red method for Albacore tuna age(2% KOH in the preparation of 0.5% alizarin red stock solution),this staining method can be used for the future use of vertebrae to identify fish age to provide an important reference.(2)When using the fins for age identification,the cutting position of the fins will produce some errors in the identification of the age.In this study,10%,20% and 50% of the total length of the fins were used as the cutting position.In the past,many experts used the base width(C)of the fins as the reference length of the cutting position.However,this study found that this would produce some errors.This study finally found that from the beginning of the study.The full length of 20% of the marker segments is optimal for the cleavage site.This study suggests that the identification of the length of the North Pacific Albacore tuna fins should be taken from the beginning of the bone.The total length of the marker is 20%.(3)The length of the long-finned tuna fork in the North Pacific is 52 ~ 122 cm,the average fork length is 84.91 ± 5.38 cm,the superior fork length is 81 ~ 90 cm.The male fork length range is 66 ~ 122 cm,the average fork length is 85.09 ± 5.07 cm,and the superior fork length is 81 ~ 90 cm.The length of the male fork is 52 ~ 114 cm,the average length is 84.73 ± 5.69 cm,the length is 81 ~ 90 cm.Univariate variance test(ANOVA)showed that there was no significant difference in the composition and body weight of male and female(P> 0.05).(4)The relationship between the total length of the Albacore tuna,the female,the male fork length and the weight of the North Pacific is:Male and female mixed:W = 2.37×10-4* FL2.419699(R2=0.8693,n=845);Female: W = 2.01×10-4* FL2.455625(R2=0.9203,n=390);Male: W = 5.03×10-4* FL2.252336(R2=0.8186,n=455).(5)Age and growth models of the North Pacific Albacore tuna based on vertebral age identification are as follows:Male and female mixed:= 109.1802 * [1-0)-0.258783(+1.99128)];Female: = 110.3774 * [1-0)-0.273284*(+1.99614)];Male: = 107.3256 * [1-0)-0.243253*(+1.93524)].The results of ARSS showed that the growth rate of female and male North Pacific Albacore tuna was not significant(P> 0.05).The inflorescence age ttp of the Von Bertalanffy growth equation of Albacore tuna was 2.25.(6)The age and growth model of the North Pacific Albacore tuna based on the age of the fins are as follows:Female + male: = 112.231 * [1-0)-0.277132*(+1.43517)];Female: = 113.156 * [1-0)-0.286375*(+1.45825)];Male: = 111.332 * [1-0)-0.276842*(+1.42321)].The results of ARSS showed that the growth of female and male North Pacific Albacore tuna was not significant(P> 0.05).The inflorescence age ttp of the Von Bertalanffy growth equation of Albacore tuna was 2.53.(7)The results showed that there were significant differences between the two groups(P <0.05),and the results were compared with those of the vertebrae and fins.The average growth index of the first stage is 5.996 ± 1.149,and the average growth index of the second stage is 1~2,3 ~ 5,6 ~ 9,the average growth index of the first stage is 5.996 ± 1.149,the average growth index of the second stage Was 3.448 ± 0.866,and the average growth index for the third stage was 1.651 ± 0.539.At the age of 3,the growth of the inflection point may be Albacore tuna tends to mature,so the growth gradually slow,slow growth at the age of 6,may be Albacore tuna has been close to the limit body length,so the growth rate slow.The Indicating that the growth of northern Pacific Albacore tuna and the general fish is very similar.(8)the use of vertebrae and fins to identify Albacore tuna age have their own advantages and disadvantages,and can be complementary.Identification of older fish can be used when the combination of fins and vertebrae two methods,identification of young fish can be used when vertebral bone identification method,so you can more accurately get the true age of Albacore tuna.