• Korean Journal of Ichthyology
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• v.23 no.1
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• pp.30-36
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• 2011

Age and growth of shotted halibut Eopsetta grigorjewi were estimated using right sagittal otoliths of 389 fish specimens from February 2004 to January 2005 in the East China Sea. Examination of outer margins of the otolith showed that the opaque zone was formed once a year and annual rings were formed from December to March. The age of specimens examined ranged from 3 to 5 years. Shotted halibut begin spawning in February and show a peak in March. Length and weight relationships showed no significant difference between females and males (P>0.05), and can be expressed as TW=$0.5091{\times}10^{-2}TL^{3,222}(r^2=0.92)$. Estimated von Bertalanffy growth curve was $L_t=46.58(1-e^{-0.14(1+1.32)})$.

• Korean Journal of Ichthyology
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• v.29 no.1
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• pp.69-74
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• 2017

Age and growth of Brown croaker Miichthys miiuy were estimated using right sagittal otoliths of 327 fish specimens from August 2015 to July 2016 in Korea. Annual rings in otoliths were formed from March to June once a year. The oldest specimens were 11 yr in female and 9 yr in male. Brown croaker began spawning in September and showed a peak in October. Total length and body weight relationships showed no significant difference between females and males (P>0.05), and can be expressed as $BW=1.15{\times}10^{-5}{\times}TL^{2928}$ ($R^2=0.98$). Estimated von Bertalanffy growth curve was $L_t=182.4(1-e^{-0.067(t+1.754)})$ ($R^2=0.96$).

• 한국해양학회지
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• v.17 no.2
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• pp.83-94
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• 1982

Specimens of eels, collected in the lagoons of Arcachon Bay from April 1977 to October 1978, were analysed for age and growty. The structure of the otolith was described based on examination of the decalccified surface using an scanning electron microscope, and was compared with obcervations made under an optical microscope. The otolith of Arcachon eels show a narrow summer growth stop in addition to a growth stop formed in winter. The narrow summer growtu in length of sedentsry eels was well represented removal of the large memgers by the migration to the sea decreases the growth ratio of sedentary eels as the fish grows older. This size selective migrationin part contributes to satisfy Von Bertalanffy's assumption. Length distribution of the exceptionally large eels in relation to age was analysed ty comparing them with "normal" sedentary eesl and with silver migsating, and it is suggested that thew exceptionally large eesl consist of the anmals which probably the [apacity for growth wen alredy young.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.556-565
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• 2018

The age and growth of butter clams Saxidomus purpuratus were estimated using transmitted light on the shells of 364 samples from January 2017 to December 2017 in Jinhae Bay. Based on monthly variation in the marginal index (MI) of the shell, it is assumed that rings are formed once a year during the period from July to August in this species. The relationship between shell length (SL; mm) and shell height (SH; mm) was expressed by the equation SH=0.8053SL-2.9636 ($R^2=0.94$) and between SL and shell width (SW; mm) by the equation SW=0.5648SL-3.7105 ($R^2=0.90$). The relationship between SL and total weight (TW; g) was expressed by the following equation: $TW=0.00009SL^{3.2141}$ ($R^2=0.96$). von Bertalanffy's growth parameters were estimated using the regression wizard in the SigmaPlot computer program (Systat Software, Inc., v. 10.0). The maximum shell length ($SL_{\infty}$) was 126.16 mm, growth rate was 0.2030/year, theoretical age at shell length 0 ($t_0$) was -0.52 years, and asymptotic total weight ($TW_{\infty}$) was 509.17 g. Growth curves for SL and TW fitted to the von Bertalanffy's equation were expressed as follows: $SL_t=126.16(1-e^{-0.2030(t+0.52)})$, $TW_t=509.17(1-e^{-0.2030(t+0.52)})^{3.2141}$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.550-555
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• 1999

The growth and spawning time of juvenile Ammodytes personatus were analyzed based on the daily growth increment in otolith reading of the sample caught in the coastal waters of Shinsudo, Sacheon from March 20 to May 1, 1988. Daily growth increment in otolith was formed once a day. The estimated spawning time ranged from November, 1987 to March, 1988. The von Bertalanffy growth model and the Gompertz growth model were expressed as, $TL=87.80(1-e^{-0.0074(t+10.79)})$ and $TL=72.59 e^{-1.8417\;e-0.0152t}$ respectively, where TL is total length in mm, t is age in day.

• Korean Journal of Environment and Ecology
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• v.25 no.3
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• pp.318-326
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• 2011

The population ecological characteristics of the Crucian carp, Carassius auratus, were determined in order to estimate stock of the mid-upper system of the Seomjin River. The fish ranged in size from 95 to 288mm total length. The age was determined by counting the scale annulus. The scales displayed clear annulus that were used to estimate the age. The oldest fish observed in this study was 5 years old. Age-2 fishes were the most numerous in the sample(n=38), followed in frequency be age-3(n=22). Marginal index analysis validated the formation of a single annulus per year. The relationship between body length and body weight was BW = $0.0038BL^{3.73}$($R^2$=0.96) (p<0.01). The relationship between the scale radius and body length was BL = 2.362R+2.76($R^2$=0.89). The von Bertalanffy growth parameters estimated from a non-linear regression method were $L_{\infty}$=33.2 cm, $W_{\infty}$=1,798.4 g, $K=0.20year^{-1}$ and $t_0$=-0.51year. Therefore, Growth in length of the fish was expressed by the von Bertalanffy's growth equation as $L_t=33.23$($1-e^{-0.20(t+0.51)}$)($R^2$=0.98). The annual survival rate was estimated to be 0.427year$^{-1}$. The instantaneous coefficient of natural mortality of estimated from the Zhang and Megrey method was $0.784year^{-1}$, and instantaneous coefficient of fishing mortality was calculated $0.067year^{-1}$. From the estimates of survival rate, the instantaneous coefficient of total mortality was estimated to be $0.851year^{-1}$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.567-577
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• 1996

This study is to estimate population ecological parameters, including growth parameters, survival rates, instantaneous coefficients of natural and fishing mortalities, and age at first capture, as well as growth rates at age of the hairtail, Trichiurus lepturus Linne in Korean waters. For describing the growth of the hairtail, three growth models were fitted, and the von Bertalanffy growth model was adopted for the purpose of the further stock assessment work. The von Bertalanffy growth parameters estimated from a nonlinear regression using EXCEL Solver were $L_\infty=46.01cm$, K=0.3868, and $t_0=-0.3220$. Annual survival rate (S) of the hairtail was estimated to be 0.277 (variance=0.00035) and the instantaneous coefficient of natural mortality (M) was estimated to be 0.441/year. Instantaneous coefficient of fishing mortality (F) for the recent years was calculated as 0.843/year, implying an impact from fishing about two times greater than that of natural mortality. The age at first capture $(t_c)$ was estimated to be 0.787 years, which is much younger age than $50\%$ mature age. Finally, the growth rates at age were estimated.

• Korean Journal of Environment and Ecology
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• v.20 no.4
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• pp.391-399
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• 2006

The population dynamics of Zacco koreanus in the upstream and downstream of Hoengseong Lake, Korea were investigated from April to October 2005. As the result of a comparison of variations regarding the time of I koreanus populations, it was confirmed that downstream was a place to remain compared to upstream Also the b value, assessed by Length-weight relationship in upstream and downstream, were $3.21{\sim}3.35,\;and\;2.94{\sim}3.37$, respectively indicating the fish in downstream had better than upstream. Additionaly condition factor(K) of each population in upstream and downstream were $0.0292{\sim}0.0693\;and\;-0.0165{\sim}0.0499$, respectively, K value in upstream lower than downstream. On the other hand, the maximum-growth value$(L_{\infty})$ calculated by von Bertalanffy's growth model in upstream and downstream were 279.7mm and 303.9mm, respectively, indicating that the potential-growth ability of population in downstream was higher than population in upstream. Therefore, Z. koreanus population in upstream became worse based on matters of age structure, Length-weight relationship, and von Bertalanffy's growth model. These results are considered to show the change of the physical environment by the constructing of Hoengseong Dam.

• The Korean Journal of Malacology
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• v.27 no.1
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• pp.1-7
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• 2011

Age and growth of the short-necked, Ruditapes philippinarum were collected from Goheung coast in Korea. Relative growth equations among SL, SH, SW and TW of Ruditapes philippinarum were ranged from 0.8059 to 0.8859. The ring radius were estimated from a von Bertalanffy method with the values of $SL_{1.58}=12.51{\pm}2.55\;mm$, $SL_{2.58}=20.27{\pm}3.08\;mm$, $SL_{3.58}=26.90{\pm}2.49\;mm$, $SL_{4.58}=31.35{\pm}3.62\;mm$, $SL_{5.58}=35.45{\pm}3.54\;mm$, $SL_{6.58}=38.78{\pm}4.04\;mm$. Back calculated total weight at the formation of annual ring on the shell of Ruditapes philippinarum with the values $TW_{1.58}$=0.35 g, $TW_{2.58}$ = 4.62 g, $TW_{3.58}$ = 5.84 g, $TW_{4.58}$ = 6.71 g, $TW_{5.58}$ = 7.50 g, $TW_{6.58}$ = 8.14 g. Growth curves for shell height and total weight fitted to the von Bertalanffy equation were expressed as: $SL_t= 51.01(1-e^{-0.1738(t+1.07)})$ $TW_t = 11.65(1-e^{-0.1738(t+1.07)})^{2.9519}$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.1
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• pp.51-56
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• 2004

Age and growth of three-lined tonguefish (Cynoglossus abbreviatus) were studied using samples from the waters off Yosu, Korea, from June to December, 2001. Sagittal otoliths had relatively clear annuli. Each annulus was formed once a year in April. The peak of the gonadosomatic index occurred also in April. The oldest fish observed in this study was 5 years old for females and 4 years old for males. The relationship between the otolith radius (R) and total length (L) was as follows: L=14.921R-2.5318 for females and L=13.527R-0.5584 for males. The relationship between total length and body weight (W) was as follows: $W=0.0008L^{3.54}$ for females and $W=0.0029L^{3.14}$ for males. The growth in length of the fish was expressed by the von Bertalanffy's growth equation as: $$L_t=44.54(1-e^{-0.16(t+2.69)})\;for\;females\;and\;L_t=41.52(1-e^{-0.15(t+3.34)})\;for\;males$$.