• 한국수산과학회지
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• 제47권4호
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• pp.419-423
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• 2014

We consider changes in the fishing ground of the small yellow croaker Larimichthys polyactis and discuss their utility in predicting fishing conditions for this species. The fishing ground, which having been formed around Jeju Island since the 1970s, is dominated by the Yellow Sea Bottom Cold Water (YSBCW), and variation in its southward expansion from the Yellow Sea is the single most key environmental factor affecting the L. polyactis catch. When the YSBCW showed strong expansion and the fishing ground shifted to the west and southwest of Jeju Island, as occurred in the late 1980s, late 1990s, and early 2000s, the L. polyactis catch was low; conversely, when expansion was weak, as in the early 1990s and late 2000s, the L. polyactis catch was high. This relationship was statistically significant and should be useful in predicting fishing conditions for L. polyactis.

• 환경생물
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• 제38권4호
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• pp.507-517
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• 2020

본 연구에서는 외부형태적으로 매우 비슷한 참조기(Larimichthys polyactis) 와 부세(L. crocea)의 두 종 간 구분을 위해 계측형질 분석을 포함한 몇가지 기법들을 수행하였다. 총 48개의 계측형질 중 4개의 유의한 차이를 보이는 계측형질이 파악되었으며(p<0.05) classical dimension에서는 유의한 차이를 보이는 계측형질은 없었다(p>0.05). 오히려, 2가지의 truss dimension(Insertion of dorsal fin base origin of pectoral fin base와 Origin of anal fin base - origin of pectoral fin base)와 2가지의 head part dimension (Most anterior extension of the head - above of eye와 Above of eye posterior aspect of operculum)에서는 유의한 차이가 나타났다(p<0.05). 하지만, 이러한 4가지 계측형질 중 head part dimension의 Above of eye - posterior aspect of operculum의 계측형질을 제외한 나머지 3가지 계측형질들에서 부세가 참조기에 비해 더 큰 수치를 나타내었다(p<0.05). X-ray 분석 결과 curved vertebral column에서 부세는 45.1±2.34°로 참조기의 38.4±1.82°에 비해 8.4% 더 큰 수치를 나타내었다(p<0.05). 머리부위의 표피를 제거한 후의 유상돌기는 두 종에 모두 존재하여 일반적으로 참조기에서만 유상돌기가 존재한다고 알려진 바와는 달리, 유상돌기는 두 종을 구분하기 위한 형질로 볼 수 없었다. 본 연구 결과는 참조기와 부세에서 일부 외부 체형에 의해 명확히 구분 가능함을 시사한다.

• 한국수산과학회지
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• 제53권4호
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• pp.650-655
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• 2020

Chilsan-do Island, South Korea, has previously been identified as one of the biggest spawning sites of the small yellow croaker Larimichthys polyactis in the Yellow Sea. To determine whether Chilsan-do still serves as a spawning site for L. polyactis, three to five stations around Chilsan-do Island were surveyed for eggs from April to June (the main spawning season of L. polyactis) in 2019, using an RN80 net. For the first time, three L. polyactis eggs were identified at two stations, located just in front of Chilsan-do Island and between Chilsan-do and the coastline, only in May. The diameter of L. polyactis eggs (1.26-1.34 mm) was very similar to those of Collichthys niveatus (1.30-1.37 mm) and Setipinna tenuifilis (1.34-1.35 mm). During the survey period, the sea surface salinity remained constant (32.0-32.1 psu), but the sea surface temperature (SST) rapidly rose from 13.6-13.7℃ in April to 22.1℃ in May. Our findings suggest that L. polyactis still spawns near Chilsan-do Island today, but on a very small scale, and that changes in SST promote spawning of L. polyactis.

• 한국발생생물학회지:발생과생식
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• 제23권1호
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• pp.73-78
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• 2019

To clarify the cytogenetic features of the chicken grunt, Parapristipoma trilineatum, small yellow croaker, Larimichthys polyactis, and brown croaker, Miichthys miiuy, in Jeju, Korea, karyotype analysis was performed. The karyotype of chicken grunt and brown croaker consists of 24 pairs of telocentrics [2n=48, fundamental number (FN)=48], and small yellow croaker consists of 3 pairs of submetacentrics and 21 pairs of telocentrics (2n=48, FN=54). No evidence of polymorphism, including aneuploidy or sex-related heteromorphic chromosomes, was found in any specimens examined in this study.

• 한국어병학회지
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• 제35권1호
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• pp.135-140
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• 2022

In this study, we determined the cause of a disease outbreak in small yellow croaker(Larimichthys polyactis) in Jeju island. The major external signs in the dead fish were hemorrhage of the skin. Vibrio harveyi were isolated from a few fishes and viruses were not detected from the diseased fish. However, flukes were confirmed on the skin and we conducted molecular identification and phylogenetic analysis of the isolated parasites. The obtained 28S rRNA sequence of our specimen(Accession No. OM333244) showed the highest homology with Neobenedenia girellae, while the COI sequence of our specimen showed the highest homology with N. melleni. Further sequence analysis with other genes and morphological observation are necessary for accurate identification.

• 한국수산과학회지
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• 제42권5호
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• pp.518-522
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• 2009

The mesh selectivity of drift gill net for yellow croaker (Larimichthys polyactis) was examined in field experiments with six different net mesh size (40, 45, 50, 55, 60 and 65 mm) from April to December, 2008 in the northwestern coastal waters of Gageo-do, Korea. The total catch of 8,091 consisted of yellow croaker (n=7,574; 89.5% of total catch), common mackerel (n=162; 4.8%) and other species (n=355; 5.8%). The selectivity curve for the small size yellow croaker was fit by Kitahara's method to the polynomial equation S(R)=exp{($-0.552R^3$+$4.927R^2$-11.591R+9.320)-6.717}. The optimal mesh size for 50% retention for minimum landing size(191mm) of yellow croaker was estimated as 51.1 mm. This is very similar to the current drift net mesh size used in Gageo-do.

• 수산해양기술연구
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• 제49권4호
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• pp.440-448
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• 2013

Estimations on population ecological parameters of the small yellow croaker, Larimichthy polyactis in Korean waters, were calculated using catch data based on coastal and offshore drift gillnet fishery and biological data from 2010 to 2012. The population ecological parameters included survival rate, instantaneous coefficient of natural and fishing mortality and age/length at first capture. The survival rate (S) of the small yellow croaker was estimated to be 0.20 from catch curve method. The instantaneous coefficient of natural mortality (M) was estimated to be 0.46/year with Alverson and Carney method. The instantaneous coefficient of total mortality (Z) was 1.611/year, used to be transformed the survival rate and the instantaneous coefficient of fishing mortality (F) were 1.153/year. The length at first capture ($L_c$) was 19.1cm by Pauly method, and the age at first capture ($t_c$) was 1.303 years of the small yellow croaker by the coastal and offshore drift gillnet fishery.

• Animal cells and systems
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• 제14권1호
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• pp.45-51
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• 2010

Genetic variation was surveyed at the mitochondrial control region (766bp) to test for the presence of genetic stock structure in the small yellow croaker, Larimichthys polyactis from the Yellow and East China Seas. Individuals of the small yellow croaker could not be distinguished on the basis of its location, as demonstrated using the neighbor-joining (NJ) method, unweighted pair-group method, arithmetic average (UPGMA) and the minimum spanning network (MSN). Analysis of molecular variance revealed no significant differences among collections of the small yellow croaker taken from the four locations (two locations each in Korea and China). Neutrality tests and a mismatch distribution analysis indicated that this species has recently expanded. Our findings suggest either that the small yellow croaker has a high migration capability that enables it to overcome the effects of genetic drift, or that this species expanded relatively recently and has not yet had sufficient time to differentiate.

• 한국수산과학회지
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• 제56권2호
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• pp.228-242
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• 2023

We examined the osteological development of the cranium, visceral skeleton, pectoral girdle, vertebral column, fins, and pterygiophore of small yellow croaker Larimichthys polyactis cultured at the Jeju Fisheries Research Institute. At 5.89 mm NL (notochord length), the larvae already had ossified frontal and basioccipital bones, parasphenoids, and vomer in the cranium. All elements of the visceral skeleton except the metapterygoid were ossified at 5.89 mm NL. Preorbital bone was ossified at 8.11 mm SL (standard length), and suborbital bones were ossified at 12.90 mm SL. In the vertebral column, ossification proceeded from the first to last centrum. The urostyle ossified at 7.41 mm SL. The caudal skeleton ossified at 6.78 mm NL, along with three hypural bones. In the pectoral girdle, the cleithrum, supracleithrum, postcleithrum, and post-temporal bones ossified at 5.89 mm NL. Caudal fin ossification began at 6.19 mm SL and was complete at 7.16 mm SL. Dorsal and anal fin ossification began at 7.16 mm SL and was complete at 8.62 mm and 8.11 mm SL, respectively. Anal and dorsal pterygiophore bone ossification was complete at 9.86 mm and 11.54 mm SL, respectively, and that of the supraneural bones was complete at 9.60 mm SL.

• 수산해양기술연구
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• 제46권4호
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• pp.392-405
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• 2010

The population of small yellow croaker, Larimichthys polyactis, in the Yellow and East China Seas has decreased significantly since the mid 1970s. Several management measures have been introduced to conserve it, but population size remains low. To rebuild this population, it is now necessary to consider more effective management methods based on the stock assessment. To determine long-term population changes, fishery and biological data collected over 34 years (1969-2002) were analysed. Yearly fish length compositions were analysed for the time periods 1968 through 1970, 1978 through 1982, and 1993 through 2002; and catch data was available from 1969 to 2002. Annual population sizes were calculated based on length composition, the relationship between total length and body weight, and total landings. Analyses showed that since the 1970s, average size of harvested fish decreased; the proportion of less mature fish (smaller than the 50% maturity length, 19cm) in catches has increased and the estimated biomass has decreased significantly. Consequently, the main management recommendation is that juvenile fish need to be better protected to allow the rebuilding of resources to a more sustainable population level. This will require fish size limit, permissible mesh size, and closed area and season regulations.