• Korean Journal of Ichthyology
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• v.18 no.2
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• pp.119-128
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• 2006

Fish assemblages associated with eelgrass beds and unvegetated area were compared based on specimens collected every month in Jindong Bay. The common fish species were Hexagrammos otakii, Acanthopagrus schlegeli, Lateolabrax japonicus, Pholis nebulosa, P. fangi, Leiognathus nuchalis, Repomucenus valenciennei, and Acanthogobius flavimanus. H. otakii, A. schlegeli, P. nebulosa and L. japonicus were higher abundance in an eelgrass bed than unvegetated area, whereas P. fangi, R. valenciennei and A. flavimanus were higher in unvegetated area. Sillago japonicus, Hippocampus japonica, Takifugu niphobles, Pseudoblennius percoides, Sebastes inermis, Syngnathus schlegeli, Sebastes schlegeli were found in an eelgrass bed, but not in unvegetated area. Most of fish species were primarily small fish species or juveniles of fish species in an eelgrass bed, while larger fish species were found in unvegetated area. The eelgrass bed in Jindong Bay seem to play a nursery role for fishes. Seasonal variations in both species composition and abundance were large in two habitats; higher number of species and individuals occurred May 2002, and April 2002 to July 2002, while biomass was the highest in April 2002 and July 2002. Fish numbers as well as biomass were lowest in January 2002. Species richness, number of individuals and biomass of fishes in an eelgrass bed were significantly higher than those of in unvegetated area. These result suggest that differences in fish species richness and abundances are primarily related to habitat structure. Different habitat preferences were evidenced for the juveniles and adult of several fish species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.805-809
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• 2015

The species composition of bycatch species in the coastal waters of Yeosu were determined by monthly sample collection using a gape net with wings in 2014. Of a total of 32 fishes collected, the dominant species were Ammodytes personatus, Conger myriaster leptocephali, Sebastes inermis, Trichiurus lepturus, Thryssa kammalensis, Leiognathus nuchalis, Syngnathus schlegeli, Thryssa adelae and Hexagrammos otakii. These 9species accounted for 95.2% of the total number of individuals collected. Most of the fish caught were juveniles and small fishes. Based on the results of multidemensional scaling (MDS) analysis, the bycatch fishes were divided into five group.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.5
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• pp.659-666
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• 2014

Our aim was to compare the community structure of fish in the coast of Wando Island between 2001 and 2013. Using a gape net with wings, we collected 61 taxa, wherein the most dominant species was Engraulis japonicus. The sea temperature in the middle layer of the survey station in 2001 (after June) was obviously higher than that in 2013, which was < $20^{\circ}C$. Except for Thryssa kammalensis in 2013, the log transformed individuals of seven dominant species, selected using a SIMPER (similarity-percentages procedure) analysis, decreased. Decreases in the individuals of Gobiidae spp., the warm-water species Trichiurus japonicus and Conger myriaster, and the migratory species Syngnathus schlegeli, Setipinna taty and Sardinella zunasi, which arrive in the southern coastal waters of Korea during summer-autumn, could be due to decreasing sea temperature in 2013. Thus, fish species diversity, estimated from rarefaction and k-dominance curves, declined in the coastal waters of Wando Island from 2001 to 2013, resulting in a significant difference in fish community structure.

• Journal of the korean society of oceanography
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• v.32 no.4
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• pp.202-207
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• 1997

Species composition and abundance of fish larvae were studied from May 1988 through August 1989 in the Han River Estuary and adjacent Kyunggi Bay, Korea. Of 23 taxa identified, Coilia nasus, llisha elongata, and Cyprinidae spp. were dominated. Maximum density (3,5771/1,000m)$^3$ occurred in August 1988 and minimum (3/1,m$^3$) in February 1989. O1igo- ormesohaline species dominated during ebb tides while polyhaline species during flood tides. Correspondence analysis revealed that three distinctive species groups; oligohaline species, Coilia nasus, Ilisha elongata and Cyprinidae spp., which dominated at both channels of Kwanghwa Island (stations 1, 2), mesohaline species, Sardinella zunasi and Gobiidae spp., at the mouth of Yeomha Channel (station 3), and polyhaline species, Engraulis japonicus and Syngnathus schlegeli, in the middle of Kyunggi Bay (station 4). Coilia nasus was the most abundant species and reported first time in the study area. Given the species composition and density of fish larvae, the Han River Estuary is considered to be a major spawning and nursery ground for brackish water species such as Coilia nasus, Ilisha elongata and some Cyprinidae spp.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.3
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• pp.145-154
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• 2009

Seasonal variation in species composition and abundance of shallow water fish from the Hakampo and Yeonpo beaches in Taean in the western coast of Korea were determined by the analysis of monthly samples collected by a beach seine from January to December, 2007. A total of 30 species, 964 individuals and 10,564.1 g of fish were collected from the Hakampo beach, and a total of 46 species, 4,447 individuals and 28,622.4 g of fish from the Yeonpo beach. The juveniles of coastal fish such as Chelon haematochelius, Paralichthys olivaceus, Repomucenus lunatus, Sebastes schlegelii and Takifugu niphobles were predominated in abundance. And the juveniles of pelagic migrants such as Konosirus punctatus, Sardinella zunasi and Engraulis japonicus were abundantly collected between summer and autumn. The fish collected were mainly composed of small-sized species and juveniles. C. haematochelius and migrant fish were young of the year, and commercially important fish such as S. schlegeli, P. olivaceus, Pleuronectes yokohamae and Hexagrammos otakii were 1 to 2 years old juveniles. It is considered that they use the shallow water as a nursery ground until they move out to the deeper water. The number of species and abundance were lower in the fine sand Hakamp beach than in the muddy sand Yeonpo beach where some Zostera marina were also found. In Yeonpo beach the adult of Gymnogobius mororanus preferred to live in the muddy shallow water and Syngnathus schlegeli living in the sea grass were also abundantly collected in spring in addition to resident fish and pelagic migrants in warm months. The resident species were more abundance in the Taean beach than in the beach located in the southern part of the west coast of Korea where the juveniles of pelagic migrants were more abundant.

• Korean Journal of Ichthyology
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• v.22 no.3
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• pp.179-185
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• 2010

This is a study of the fish assemblages in eelgrass beds of Geoje Bay on Geoje Island, Korea. Samples were collected by surf net monthly from June 2006 to May 2007. A total 26 species, 1,825 individuals, and 4,483.1 g of fishes were collected. The dominant species were Acentrogobius pflaumii, Aulichthys japonicus, Gymnogobius heptacanthus, Rudarius ercodes, Chaenogobius annularis, Gymnogobius urotaenia, Syngnathus schlegeli, Pterogobius elapoides, Zoarchias glaber, Takifugu niphobles, Zoarchia suchidai. These species accounted for 90.6% of the total number of individuals and 76.2% of the biomass of the fishes collected. The fish assemblages in the eelgrass beds showed clear seasonal changes; the number of fish species and individuals increased in March and were highest in September, whereas the biomass attained its highest level in May and subsequently decreased. Meanwhile the species diversity indices showed their highest value in December.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.234-243
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• 2006

A total 34 fish species, 1,110 individuals, and 5,107.3 g of fishes were collected by a surf net in the eelgrass bed in Jisepo Bay of Geoje Island, Korea. Samples were monthly collected from March 2005 to February 2006. The dominant fish species were Rudarius ercodes, Ditrema temminckii, Syngnathus schlegeli, Petroscirtes breviceps, which accounted for 73.5% of total number of individuals and 63.6% of biomass of fish collected. The number of species and biomass were low from March 2005 to July 2005, and high from August 2005 to October 2005. Species diversity indices ranged from 0.836 to 2.016, and showed the highest value in December 2005.

• Korean Journal of Ichthyology
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• v.19 no.4
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• pp.318-323
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• 2007

The feeding habits of Pacific cod (Gadus macrocephalus) were studied based on the examination of stomach contents of 192 specimens collected from November, 2005 to January, 2006 in the coastal waters off Gadeok-do, Korea. The size of Pacific cod ranged from 35 to 82 cm in standard length (SL). Pacific cod mainly consumed shrimps such as Eualus spathulirostris, Crogon hakodatei and C. affinis and fishes. Its diet also included small quantities of cephalopods, amphipods, hermit crabs and crabs. Individuals between 35 cm and 45 cm SL mainly consumed shrimps. The portion of shrimps decreased with increasing fish size, and this decrease was paralleled with increased consumption of fishes and cephalopods. In this study we found Syngnathus schlegeli in the stomach contents of many Pacific cod specimens. S. schlegeli is a typical seagrass fish species which inhabits in seagrass beds, This fact means that Pacific cods stay in the seagrass beds during spawning period. Therefore migration of Pacific cod to coastal waters off Gadeok-do during spawning period seems to be a survival strategy for its larvae and small juveniles to stay in seagrass beds which provide with abundant foods and shelters to many commercial fish species.

• Korean Journal of Ichthyology
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• v.30 no.1
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• pp.55-64
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• 2018

Fish assemblages in a sandy shore and an eelgrass bed were compared based on monthly samples in the southern coastal water of Korea. Samples were collected by a beam trawl in the sandy shore and a surf net in the eelgrass from March to February 2012. The common fish species were Syngnathus schlegeli, Pseudoblennius cottoides, Pholis nebulosa, Favonigobius gymnauchen, Gymnogobius heptacanthus, Pseudopleuronectes yokohamae, Takifugu niphobles. Among them S. schlegeli, Urocampus nanus, P. cottoides, P. nebulosa, T. niphobles were high abundance in the eelgrass bed than in the sandy shore, whereas Acanthogobius flavimanus, Acentrogobius pflaumi, F. gymnauchen, G. heptacanthus, P. yokohamae were high in the sandy shore. Aulichthys japonicus, Hippocampus coronatus, Sebastes inermis, Lateolabrax japonicus, Siganus fuscescens were found in the eelgrass bed, and Thryssa hamiltoni, Mugil cephalus, Inimicus japonicus, Platycephalus indicus, Hexagrammos otakii, Furcina ishikawae, Liparis tanakae, Repomucenus curvicornis, and Eutaeniichthys gilli were observed in the sandy shore. Species composition and abundance varied seasonally in two habitats; The number of species and abundance was high in August and September, while biomass was the highest in April and September. Fish numbers as well as biomass were lowest in February. Number of individuals and biomass of fish in the eelgrass bed were significantly higher than those of in the sandy shore. Some fish preferred to live in the eelgrass were collected in the sandy shore, while fish preferred to live in the sandy shore were rarely collected in the eelgrass.

• Korean Journal of Ichthyology
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• v.9 no.1
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• pp.48-60
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• 1997

The species composition and seasonal variations of fish community in the Zostera marina belt at the coastal water off Hamduck, northern part of Cheju Island, were analyzed based on day and night samples collected by a small beam trawl from May 1993 to May 1994. The dominant species among the 58 fish species in 35 family were tubesnout, Aulichthys japonicus, gobie, Pterogobius zonoleucus, filefish, Rudarius ercodes, pipefish, Syngnathus schlegeli and sea catfish, Plotosus lineatus. These species comprised 86.1% in the number of individuals and 62% in biomass. The number of individuals and biomass were high between October and December, and low between January and April. About 90% of fishes were noncommercial and small-sized fishes, less than 14cm in total length. The larvae and juvenile fishes were collected in the study area throughout the year. The recruitments of dominant species were related to the seasonal variations of Z. marina utilized as a shelter or feeding ground. A japonicus, P. zonoleucus, Zoarchias glaber and Hexagrammos agrammus recruited between January and June, and R. ercodes, S. schlegeli, P. lineatus and Petroscirtes breviceps between July and December.