• Ocean and Polar Research
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• 제39권4호
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• pp.279-292
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• 2017

We determined the maturity and growth of the Marbled sole, Pseudopleuronectes yokohamae based on monthly sampling in the West Sea of Korea from February 2009 to December 2010. Determination of sex of P. yokohamae was by gonadal inspection, and age and growth were determined by analyzing the otolith. The biological minimum size of P. yokohamae female was 24.5 cm. The seasonal changes in the ratio of a translucent zone to an opaque zone revealed that the end of the translucent zone of the otolith were annuli formed in May once a year. We compared 8 type growth equations with several length-at-age data. By using the length-at-monthly age data of these, the calculated von Bertalanffy growth equations were $L_t=41.7(1-e^{-0.47(t+0.24)})$ for females and $L_t=32.7(1-e^{-0.75(t+0.01)})$ for males. We estimated that 24.5 cm was the total length of 2 year old P. yokohamae spawns in the cold water season from January to April, and grows to 8 years old for females and 6 years old for males in the West Sea of Korea.

• 한국수산과학회지
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• 제55권5호
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• pp.583-589
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• 2022

The feeding habits of the marbled flounder Pseudopleuronectes yokohamae were studied using 384 specimens (10.7-52.3 cm in total length) collected from the West Sea, Korea between January and December 2021. P. yokohamae ate mainly polychaeta and gastropoda, incuding teleostei, caridea, euphausiacea, amphipoda and brachyura. The mean number of preys per stomach (mN/ST) showed a statistically significant difference, and the mean weight of prey per stomach (mW/ST) increased as the total length increased. P. yokohamae ate mainly teleostei in spring and winter. P. yokohamae ate mainly euphausiacea in summer and mainly polychaeta in autumn.

• 한국수산과학회지
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• 제49권3호
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• pp.367-375
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• 2016

Marbled flounder Pseudopleuronectes yokohamae is a commercially important flatfish in the coastal waters of the East Sea off Pohang, Korea. Maturity and spawning dynamics of P. yokohamae were investigated based on samples collected by gill net and long line in the coastal waters off Pohang from January 2013 to December 2014. We analyzed monthly changes in maturity stage, gonadosomatic index (GSI), egg diameter, fecundity, and total length at 50% group maturity. We found that the spawning period was December to February, wherein fecundity ranged from 55,760 eggs at 20.40 cm total length (TL) to 1,559,007 eggs at 46.6 cm TL. The relationship between TL and fecundity (F) was F = 0.0017 TL^3.5604 (R² = 0.6984), and F increased with increasing TL. We estimated the TL at 50% group maturity as 27.4 cm for female and 23.5 cm for male P. yokohamae, respectively. The results from this research will aid in the development of policies on season and minimum catch length for sustainable production of P. yokohamae. We propose that it is necessary to conduct long-term ecological monitoring for this species because biological properties such as spawning ecology and growth performance are being affected by climate change.

• 한국수산과학회지
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• 제50권3호
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• pp.278-286
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• 2017

The age and growth of marbled flounder Pseudopleuronectes yokohamae in coastal waters of the East Sea of Korea off Pohang were determined, by evaluating monthly samples of commercial catches, caught by gill nets and longlines from February 2013 to January 2014. New annuli from annually in P. yokohamae otoliths, and the boundary between the opaque and translucent zones forms from March to May. The relationships between total length (TL) and total weight (TW) were $TW=0.009TL^{3.128}$ ($R^2=0.969$) for females and $TW=0.008TL^{3.150}$ ($R^2=0.964$) for males. The TLs at the time of annulus formation, back-calculated from the otolith-length relationship by reference to the von Bertalanffy growth curves, were $L_t=52.63$ ($1-{\exp}^{(-0.231(t+0.033))}$) for females and $L_t=36.22$ ($1-{\exp}^{(-0.400(t+0.117))}$) for males. Commencing at the age of 3 years, females grew faster than males (P<0.05).

• 한국해양학회지:바다
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• 제19권1호
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• pp.35-40
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• 2014

2011년 2월부터 5월까지 경남 남해군 연안에서 소형 Beam trawl에 채집된 문치가자미 치어 이석을 관찰 분석하여 부화시기와 초기성장을 추정하였다. 문치가자미 치어는 2011년 2월에서 5월까지 총 175개체가 채집되었며, 체장-체중 관계식은 $W=9.76^*10^{-8}L^{4.39}$ ($r^2=0.93$)를, 체장-이석경 관계식은 L=0.0795R+0.2249 ($r^2=0.92$)로 추정되었다. 체장 성장은 $L_t=135{\exp}\{-{\exp}[0.0103(t-116)]\}$ ($r^2=0.83$)로 Gompertz 성장식이 가장 유의하게 회귀되었다. 이석 일령으로부터 추정한 주 산란시기는 12월에서 1월인 것으로 추정되었다.

• 한국어류학회지
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• 제30권1호
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• pp.55-64
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• 2018

남해 삼동면 연안의 사질과 잘피밭의 어류군집을 비교하기 위해서 2011년 3월부터 2012년 2월까지 소형 beam trawl과 지인망을 이용하여 어류를 매월 채집하였다. 두 곳의 조사지점에서 공통으로 출현한 종은 총 19종이었다. 실고기, 풀해마, 가시망둑, 돌팍망둑, 감성돔, 베도라치, 문절망둑, 줄망둑, 날개망둑, 살망둑, 두줄망둑, 문치가자미, 복섬 등이 공통으로 출현하였고, 이 중 실고기, 풀해마, 가시망둑, 베도라치, 복섬은 잘피밭에서, 돌팍망둑, 감성돔, 문절망둑, 줄망둑, 날개망둑, 살망둑, 두줄망둑, 문치가자미는 사질연안에서 주로 출현하였다. 실비늘치와 해마, 볼락, 농어, 독가시치는 잘피밭에서만 출현하였고, 풀반지, 숭어, 쑤기미, 양태, 쥐노래미, 알롱횟대, 꼼치, 동갈양태, 댕기망둑은 사질에서만 출현하였다. 채집된 어류 대부분은 소형어나 유어로 남해 연안의 잘피밭과 사질연안이 이들 어류의 성육장의 역할을 하는 것으로 생각된다. 출현 종수는 2011년 8~9월에, 개체수는 2011년 8월이 가장 높았다. 생체량은 2011년 4월과 9월에 가장 높았다. 대체적으로 겨울철에는 출현 종수, 개체수 및 생체량이 모두 낮았다. 개체수 및 생체량은 사질연안에 비하여 모두 잘피밭에서 높았으며, 사질연안에서는 잘피밭을 선호하는 어류들이 다수 출현하였지만, 잘피밭에서는 사질연안을 선호하는 어종이 거의 출현하지 않았다.

• 한국수산과학회지
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• 제48권6호
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• pp.947-959
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• 2015

Variations in the species composition, biomass and size distribution of fisheries resources in the Uljin marine ranching area were investigated using trammel nets at two stations (artificial reef and natural rocky area) from 2009 to 2010. During the survey, a total of 74 species were sampled with a mean density of 132 ind./net and mean biomass of 21.56 kg/net. In the natural rocky area, a total of 45 species were sampled at a mean density of 202 ind./net and mean biomass of 28.81 kg/net, while in the artificial reef area, samples included a total of 56 species, with means of 62 ind./net and 14.30 kg/net. The dominant species, comprising over 3% of the total number of individuals, were Suberites ficus (30.8%), Ovalipes punctatus (19.2%), Paralichthys olivaceus (11.7%), Pleuronectes herzensteini (4.7%), Kareius bicoloratus (3.5%), Pseudopleuronectes yokohamae (3.5%) and Eopsetta grigorjewi (3.0%). The dominant species, in terms of biomass, comprising over 5% of the total biomass, were P. olivaceus (22.1%), S. ficus (18.7%), O. punctatus (7.2%), Hexagrammos otakii (6.6%), P. yokohamae (5.7%), K. bicoloratus and P. herzensteini (5.3%). A cluster analysis and non-metric multidimensional scaling (nMDS) analysis based on the Bray-Curtis similarity of fourth root transformed data for number of species and individuals, was divided into two groups: the artificial reef area (group A) and the natural rocky area (group B).

• 수산해양기술연구
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• 제55권4호
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• pp.335-348
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• 2019

We found ten species of larvae belonging to the family Pleuronectidae as a result of analysis on ichthyoplankton collected monthly from the East Sea, Yellow Sea, Korea Strait and East China Sea between February 2016 and May 2018 using bongo net. The ten species of pleuronectid larvae were divided into three groups in morphology. Group A had three or four bars on the lateral side of the tail: Glyptocephalus stelleri, G. kitaharae, Pseudopleuronectes yokohamae, and Hippoglossoides dubius. Group B had a row of melanophores along the dorsal and ventral side of tail: Cleisthenes pinetorum, Eopsetta grigorjewi, Dexistes rikuzenius, and Platichthys bicoloratus. Group C had dense melanophores which are covering trunk and tail entirely except caudal peduncle: Platichthys cornutus and Platichthys japonicus. The three groups did not associate with previous molecular phylogenetic studies except for the G. stelleri and G. kitaharae of the group A.