• Korean Journal of Ichthyology
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• v.29 no.1
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• pp.80-86
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• 2017

We examined monthly variations in community structure of larval fish assemblage in the coastal waters of south-central Korea in spring and summer, 2016. A total of 31 taxa of larvae were collected during the study period. Engraulis japonicus larvae were predominated in spring than summer. The larvae of Cynoglossus abbreviates, a spring spawners, were exclusively collected in spring, while those of Nibea albiflora, a summer spawners, were exclusively caught in summer. Due to those seasonal differences in abundance of the dominant species, larval fish community was divided into two main seasonal groups (i.e. April~May and June~August). In addition, summer group was divided into two significant subgroups (June~July and August). During August, the larvae of E. japonicus and N. albiflora sharply decreased in abundance due to abnormally high sea water temperature that was raised up to $28^{\circ}C$, with the temperature being out of range of their optimum spawning temperature.

• 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.

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.294-304
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• 2023

Seasonal variations in the community structure of larval fish assemblage in the coastal waters off Gadeok-do were investigated in May, August and November of 2019, and February in 2020. During the study period, a total of 85 larvae species belonging to 45 families were collected. The dominant species were Engraulis japonica, Gobiidae sp., Clupea pallasii, Decapterus maruadsi, and Callionymidae sp.. These five species accounted for 84.1% of the total number of larvae during the survey period. E. japonica, Gobiidae sp., D. maruadsi, and Callionymidae sp. were the dominant species in the summer, while C. pallasii was the dominant species in the winter. The Species Diversity Index was highest in the summer and lower in the fall and winter months, with the lowest values in the spring. As a result of cluster analysis using the number of individual larval fish showed that they are divided into four seasonal groups. In particular, due to seasonal changes in water temperature, an appropriate growth environment was formed in the summer, and an appropriate hatching water temperature for winter spawning fish species was formed in winter, reflecting the seasonal characteristics of the larval fish community.

• Korean Journal of Ichthyology
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• v.36 no.2
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• pp.156-163
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• 2024

This study investigated the temporal patterns of species composition and abundance of larval fish assemblages through seasonal samplings in the coastal waters off Uljin, East Sea from April 2022 to February 2023. A total of 27 taxa of larval fishes were collected in the study area. The dominant fish larvae were Pseudopleuronectes herzensteini, Sebastes inermis, Ammodytes japonicus, Pseudopleuronectes yokohamae, Rudarius ercodes and Parablennius yatabei constituting 86.6% of total larval fish abundance. The number of species, abundance, and diversity index fluctuated according to season, showing the highest species number and abundance in April (spring) and diversity in July (summer). Larval fish assemblages were divided into three seasonal groups, including spring, summer and winter groups based on relative abundance of each fish larvae. Among abundant fish larvae, P. herzensteini predominated during spring, while P. yatabei and R. ercodes were abundant during summer. S. inermis, A. japonicus and P. yokohamae constituted the most abundant larval fish group during winter. These temporal changes in larval fish assemblages were attributed to seasonal changes in surface water temperature. The results from this study may elucidate our understanding of larval fish diversity and contribute to evaluating the nursery function of coastal habitats in the East Sea.

• Korean Journal of Ichthyology
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• v.27 no.2
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• pp.104-115
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• 2015

The species composition of larval fish assemblages in the Nakdong River estuary, Korea, was determined using monthly samples collected between September 2010 and August 2011 at two stations. A total of forty three larval species were collected during the study. Among forty three taxa of fish larvae, summer gobies, Clupea pallasii, Engraulis japonicus, spring gobies, Konosirus punctatus, winter gobies, Sardinops melanostictus, Coilia nasus were dominant taxa, and these eight taxa accounted for 95.0% in the total number of individuals. Species composition and abundance varied greatly spatio-temprally showing the peak abundances of fish larvae in August 2011, and a few fish larvae were occurred in November 2010. Cluster analysis based on the number of individuals of fish larvae showed that 21 month-station sampling units were classified into five groups at the similarity level of 50%, and the results of ANOSIM and SIMPER analysis revealed significant differences in community structure among five groups.

• Korean Journal of Environmental Biology
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• v.36 no.2
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• pp.140-149
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• 2018

Seasonal variations in the community structure of larval fish assemblage in Jinhae Bay were investigated in February, May, August and November of 2015, and in the same months in 2016. During the study period, a total of 28 larvae species belonging to 24 families were collected. The dominant species were Clupea pallasii, Liparis tanakae, Callionymidae sp., Sillago japonica, Ernogrammus hexagrammus and Engraulis japonica. These six species accounted for 77.6% of the total number of larvae during the survey period. The larvae of C. pallasii and L. tanakae were exclusively caught in February 2015 and 2016, while those of Apogon lineatus and Sillago japonica were exclusively caught in August 2015 and 2016. Overall, species diversity of the fish larvae was highest in February and August, although it was relatively low in May. The results of the non-metric multidimensional scaling (nMDS) analysis using the number of individual larval fish showed that they are divided into four seasonal groups. Our results showed that the community of larval fish in Jinhae Bay was affected by seasonal changes in temperature and the emergence of spawning fish species. Additionally, we suggest that the high abundance of larval fish came from around Jam-do and the northern part of Chilcheon-do; these locations are the main spawning grounds of Jinhae Bay.

• Korean Journal of Ichthyology
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• v.23 no.1
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• pp.37-45
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• 2011

Seasonal variation in species composition and abundance of fish larvae assemblages in the south-western Jinhae Bay were investigated monthly in 2009. During the study period, 49 larvae species belonging to 24 families were collected. The dominant species were Clupea pallasii, Hexagrammos otakii, Konosirus punctatus, Engraulis japonicus, Parablennius yatabei, and Omobranchus elegansei. These six species accounted for 92.7% of the total number of individuals collected. The number of species, number of individuals, and species diversity indices fluctuated with the seasons. The peak number of species and individuals occurred in July and January, respectively. Principal component analysis(PCA) and correlation analysis showed that variation in monthly water temperature could act as an indicator of seasonal variation in community structure and abundance of the dominant species; in particular, those of C. pallasii, H. otakii, E. japonicus and P. yatabei corresponded with the water temperature.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.6
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• pp.759-766
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• 2017

In order to identify the species composition and distribution pattern of larval fish assemblages in the southern coastal waters of Korea, monthly samples were taken using an RN80 net which was towed horizontally in three different regions (Yeosu, Namhae and Tongyoung) between May to September 2016. A total of fifty taxa were collected during the study. Among these, Engraulis japonicus, which accounted for 56.8 % of the total population, was the most dominant species, followed by Sillago japonicus, Parablennius yatabei, Gobiidae Type A, Parablennidae sp., and Omobranchus elegans as dominant taxa, that accounted for 87.5% of the total number of individuals. ANOSIM results revealed that regional groups were not separated, but seasonal groups were clearly divided with statistical significance, and these differences were caused mainly by water temperature variations identified by canonical analysis.

• Korean Journal of Ichthyology
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• v.7 no.2
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• pp.177-186
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• 1995

To study the fish larval community in the coastal waters off Shinsudo, Samchonpo, samples were collected with long bag net at 2 stations from October 1986 to September 1987. Forty-four species in 29 families were collected during the period of investigation. Engraulis japonicus, Enedrias nebulosus, Ammodytes personatus and Astriconger myriaster predominated in fish assemblage. These four fish species accounted for approximately 96.79% in number and 73.94% in biomass. Number of species, number of individuals and biomass were high during the spring, but low in summer. A peak of diversity(H') for number was found in April 1987, and that for biomass was in October 1986. Four showing dominant species had their own seasonal abundance patterns, a peak of abundance between the species at 2 months intervals.