• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.4
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• pp.404-409
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• 1999

The in situ target strengths of, maurolicus muelleri were measured by the split beam echo sounder system at the frequency of 38kHz.Target strengths were measured during the night time in order to obtain the pure separated echoes from the scattered individual. And also it was to establish reasonable threshold due to taking the signals like as the planktons and etc.Since Maurolicus muelleri is a typical micronektonic fish, they mainly consisted of deep scattering layers(DSLs), and had a vertical migration perrodically during daytime and at night.We found that the Maurolicus muelleri occupied about 99% of total catch. Total length ranged from 4.5 to 5.7cm with a mean of 5.2cm and a standard deviation of 0.22cm.The target strengths of Maurolicus muelleir ranged from -60.4 to - 52.7dB and -59.2 to - 52.5 dB in the water layer of 10~30m and 30~50m depth, perspectively. Mean target strength was -57.1dB/fish and -28.5dB/kg. The target strength had the relation with the total length of the fish as, TS=20logL-71.4.

• Korean Journal of Ichthyology
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• v.10 no.2
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• pp.176-183
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• 1998

Spawning ecology and feeding habits of Maurolicus muelleri in the Korean waters were studied. M. muelleri spawned continuously throughout the year showing a peak in August. Major spawning ground of this species was the southeastern sea of Korea. The fecundity observed from the ovaries of M. muelleri showed a range of 5,072 to 32,117, and the average number of eggs per one spawning time was approximately 250. M. muelleri was a zooplanktivore which fed mainly on copepods. Its diets also included various crustaceans such as amphipods, euphausiids, shrimps and mysids.

• Korean Journal of Ichthyology
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• v.11 no.1
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• pp.62-71
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• 1999

The seasonal distribution of Maurolicus muelleri eggs and larvae were determined using samples collected from the Korea Strait and the southern part of the East Sea in May and November, 1992, August, 1993, and January, 1994. The eggs were most abundant in summer and the larvae in spring, while, their abundance was low in winter. The eggs were mainly found from in all season around sea of the front area of latitude $35{\sim}36^{\circ}N$ and the West Channel of the Korea Strait found the middle or bottom water lower than $15^{\circ}C$. The seasonal distribution of the eggs in the western Korea Strait varied according to the structure of the bottom cold water of the Korea Strait. The M. muelleri larvae in different stage were most abundant in the front area of latitude $35{\sim}36^{\circ}N$. The spawning and hatching area of the M. muelleri was considered to be the front area located in the shelf break, and some eggs can be transported into the Korea Strait by westward cold bottom current in summer. The Korea Strait would be the southern margin of the distribution of Maurolicus muelleri eggs and larvae of the East Sea.

• Ocean and Polar Research
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• v.24 no.4
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• pp.443-448
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• 2002

A study on the ichthyoplankton assemblage was conducted around Dokdo in the East Sea in September 1999 and May 2000. Sixteen species of fish larvae including eggs were collected during the surveys. Anchovy (Engraulis japonicus) eggs and larvae were comprised of 2.0% and 94.5% of total samples in number, respectively. Muller's pearlside (Maurolicus muelleri) eggs and larvae were comprised of 95.0% and 3.2%, respectively. The other species mostly composed of warm water species were less than 2% of total samples in number. The number of species and abundance of the fish lawae and eggs were higher in September than in May. Although there were limited data on the ichthyoplankton around Dokdo in summer and winter, this study area seems to be used for the spawning or nursery ground of fishes.

• Korean Journal of Ichthyology
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• v.3 no.1
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• pp.11-23
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• 1991

To study the distribution of inhthyoplankton in the adjacent water of Wolsong, samples were collected using Bongo net from the surface water in November of 1989, and February, May and July of 1990. Fish eggs were divided into Engrualis japonicus, Callionymidae, Maurolicus muelleri, Konosirus punctatus, and others. The dominant species of fish eggs were Maurolicus muelleri and Callionymidae accounting for 60.1% and 13.7% of the total egg abundance, respectively. Total of 21 taxa of fish larvae occurred. The predominant species was Engraulis japonicas accounting for 61.2% of the total lavae, and bollowed by Callionymidae(11.9%). Other major species were Maurolicus muelleri, Gobiidae sp., Ammodytes personatus, Sebastes inermis, S. Pachycephalus, Scartella cristata, and Sebastiscus marmoratus. These 9 taxa constituted 96.5% of the total larvae collected. In this area, where upwelling occasionally occurs the distribution of fish eggs and larvae appeared to be affected by the transport of the surface water during the upwelling period.

• Korean Journal of Ichthyology
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• v.7 no.1
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• pp.64-70
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• 1995

Vertical distribution of eggs and larvae of Maurolicus muelleri were studied in the south-eastern waters of Korea during 1985 and 1986. Samples were collected vertically at three different layers, 0~30 m, 30~50m and 50~100m. The densities of egg and larva were high in August. Eggs and zooplankton were abundant around the thermocline in the temperature range of $10{\sim}15^{\circ}C$ at the layers of 50 m depth in 1985, and 30~100m depth in 1986. Eggs in the cleavage stage were abundant at the layer of 50~100m depth, while those of processing embryonic body formation were tended to concentrate at the layer of 30~50m depth. The vertical distribution of each developmental stage differed according to sampling time. They were distributed uniformly at water column from 30 m to 100m depth in the midnight, but concentrated at the layer from 30 m to 50 m from dawn to sunset. Before and after midnight, eggs in the cleavage stage were most abundant. It was assumed that M. muelleri spawned at the layer of 50~100m depth around the midnight, and the eggs ascended to the layer of 30~50m depth with development.

• 한국해양학회지
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• v.15 no.2
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• pp.79-88
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• 1980

Diaphus suborbitalis는 일본 준하만에 있어서 중 심층성 어류 micronekton의 주요종이다. 본연구에서는 본종의 생태규명의 일환으로서 지리분포와 일주수직이동의 양식을 밝혔다. 시료는 1971년 5월부터 1977년 4월까지 동경대학 해양연구소 연구선 담청환과 저인망어선에서 채집했다. 채집에는 6ft.의 IKMT, 구경 160cm의 대형플랑크톤네트(ORI), 구경 56cm의 MTD플랑크톤네트와 저인망을 사용했다. 1971년 5∼6월의 만내전역에 걸친 조사에 의하면, 본종은 연안성이 강하여 만의 안쪽부분으로부터 만서부에 있어서의 200∼500m 등심선에 따른 해역에 분포의 중심을 갖고, 만중앙부와 만남동부 및 만입구에서는 출현량이 적다. 이것은 본종이 Sergestes lucens, Diaphus watasei, Maurolicus muelleri등과 함께 만내에서 대륙붕사면 주변해역에 분포의 중심을 갖는 생물군집의 일원임을 나타내고 있다. 어군탐지기와 Net채집에 의한 시료에 의하면, 본종의 층간의 서식층은 수심 200∼400m 전후의 대륙붕사면의 근저층이다. 일몰시부터 음파산란층(DSL)을 형성하는 다른 생물과 함께 상승하기 시작하여, 야간은 수심 50m 전후층을 중심으로 분포한 후 새벽녘에 하강을 개시하여 다시 층간의 서식층으로 이동한다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.295-302
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• 1999

To study the distribution of ichthyoplankton in the adjacent waters of Yousu, ichthyoplankton were sampled 4 times (September 1996, November 1996, February 1997 and May 1997). Four species of fish eggs and twenty-four species of fish larvae were identified. Among fish eggs, Engraulis japonicus eggs were the dominant species comprising $80.6\%$ of the total fish eggs collected, followed by Callionymidae spp. $1.6\%$, Konosirus punctatus and Maurolicus muelleri occupied below $1.0\%$ respectively, while $17.8\%$ were unidentified. Most larval fish species were found in September (17 species). In fish larvae, Callionymidae spp. was the dominant species occupying $25.7\%$ of total fish larvae collected and than followed by Gobiidae spp. $23.5\%$, Sillago japonica $17.2\%$ Engraulis japonicus $12.2\%$, Omobranchus elegans $9.9\%$ and the unidentified species were less than $2.0\%$. The larvae fish species collected in this study area were comprising the coastal sedentary species (Gobiidae, Callionymidae, Hexagrammos otakii and io on), and the warm water species (Auxis spp. and Coryphaena hipurus and Pomacentridae spp.) which were appearing by warm water current flowing near the costal area of Cheju Island.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.633-642
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• 1994

Distribution of ichthyoplankton in the adjacent waters to Kori were surveyed during the period from April, 1991 to January, 1992. The dominant fish eggs included the eggs of Engraulis japonica, Maurolicus muelleri, Callionymus spp. and others. The eggs of Engrualis japonica and Maurolicus muelleri were $79.52\%$ and $1.86\%$ of the total eggs abundance, respectively. A total of 15 taxa of fish larvae were found. The dominant species was Engraulis japonica accounting for $52.39\%$ of the total larvae and followed by Callionymidae fish($29.36\%$). Other major species were Stephanolepis cirrhifer($6.30\%$), Sebastes schlegeli($3.16\%$), Ammodytes personatus($1.33\%$) and Girella punctata($1.70\%$). These 6 taxa constituted $94.30\%$ of the total larvae collected. In this area, distributions of warm water had a great influence on larvae and juvenile distribution which usually is along the coast and the other places where there layer water movements since, upwelling in the open sea affects ichthyoplankton distribution.

• Korean Journal of Ichthyology
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• v.11 no.1
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• pp.72-85
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• 1999

A study on the larval fish assemblage around the front area was conducted in the Korea Strait in August, 1993. The front was found in the shelf break located in $35{\sim}36^{\circ}N$. A total of 125 species were found in the study area. Of these Engraulis japonicus was the most dominant species comprising 84.3% of the total fish larvae collected and followed by Maurolicus muelleri accounting for 7.7%. Gobiidae, Callionymidae and Pomacentridae showed higher frequency of occurrence. These five species can be divided into three groups. First group was comprised in the larval fish species such as E. japonicus and Callionymidae which were found in the whole study area. The second group was comprised of Gobiidae and Pomacentridae which were found in the warm area located in the southern part of the front area. The other species was M. muelleri found in the cold area located in the northern part of the front area including the front area. The assemblage, geological distribution and body length composition of the fish larvae in the Korea Strait would be mainly determined by the spawning ecology of the fishes, and the geological distribution and structure of the front which is formed in the ocean boundary between the Tsushima Current and the East Sea Cold Water.