• Korean Journal of Ichthyology
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• v.24 no.2
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• pp.77-83
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• 2012

The feeding habits of the marbled flounder Pleuronectes yokohamae were studied using 395 specimens collected from January to December, 2010, in the coastal waters off Tongyeong, Korea. The size of P. yokohamae ranged from 10.5 to 38.8 cm in standard length (SL). P. yokohamae is a bottom-feeding carnivore that consumes mainly bivalves, amphipods and polychaetes. Its diet also includes small quantities nemertians, anthozoan, isopods, copepods, tanaidacean, shrimps, crabs and ophiuroids. Our feeding-strategy graphical method reveled that P. yokohamae was a generalized feeder, with a wide niche width. P. yokohamae mainly consumed bivalves, amphipods and polychaetes, and did not show significant ontogenetic changes in feeding habit without size over 22 cm. Prey size did not increase significantly as growing fish size.

• Korean Journal of Ichthyology
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• v.23 no.4
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• pp.300-304
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• 2011

The reproductive characteristics of Chaenogobius gulosus was examined using 333 specimens collected monthly between October 2008 and September 2009 in the coastal waters of Tongyoung, Korea. Specimens ranged from 2.0 to 12.6 cm in standard length (SL). The gonadosomatic index (GSI) of females was highest in February and decreased until April, with the spawning season lasting from December to April. The monthly ratio of female to male did not significantly differ (${\chi}^2$-test, p>0.05). The size at 50% maturity for females was 7.9 cm SL. Fecundity ranged from 1,112 to 6,059 eggs, with a mean of 3,011 eggs.

• Korean Journal of Ichthyology
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• v.22 no.1
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• pp.41-48
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• 2010

The feeding habits of Chaenogobius gulosus were studied based on an examination of the stomach contents of 333 specimens collected between October 2008 and September 2009 in the coastal waters of Tongyeong, Korea. The specimens ranged in standard length (SL) from 2.0 to 12.6 cm. C. gulosus is an omnivore and consumes mainly seaweeds (such as Ulva pertusas), crabs and gastropods. Its diet also included small quantities of bivalves, polychaetes, insects, shrimps, mysids and amphipods. Smaller individuals (<6 cm SL) consumed mainly gastropods. The proportion of these prey items decreased with increasing fish size, and this decrease paralleled the increased consumption of seaweeds. Seasonal changes in the diet of C. gulosus were significant. Seaweeds were consumed more during spring and summer compare with other seasons.

• Korean Journal of Ichthyology
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• v.22 no.3
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• pp.201-205
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• 2010

One specimen of a natural hybrid of an Oplegnathus (Oplegnathus fasciatus $\times$ Oplegnathus punctatus) was found in Tongyeong, Korea in August 2008. We, herein, describe its morphological and genetic characteristics and compare them with those of O. fasciatus and O. punctatus. In morphology, the hybrid showed many distinctive black rounded blotches on body sides and four faint vertical bars, being in those features similar to O. punctatus. Although the counts and measurements of the hybrid mostly overlapped between O. fasciatus and O. punctatus, the Oplegnathus hybrid resembled O. punctatus in the ratio of pelvic-fin length in standard length: Oplegnathus hybrid (26.7%) was closer to O. punctatus (26.4%) than to O. fasciatus (17.2~23.6%). In genetics, as a result of analysis of 510 base pair sequences of mitochondrial DNA 16S rRNA, the hybrid was closer to O. fasciatus (d=0.000~0.010) than to O. punctatus (d=0.020). Our results suggest that the natural hybridization represented by the subject specimen occurred between an O. fasciatus female and an O. punctatus male.

• Korean Journal of Ichthyology
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• v.25 no.3
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• pp.163-168
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• 2013

Two flatfish species were collected between January 2010 and August 2010 from fishing vessels operating with fishing, gill net and shrimp trawls along the coastal waters off Tongyeong, Korea in order to examine feeding habits. Kareius bicoloratus fed mainly on bivalves and fishes, whereas Clidoderma asperrimum fed mainly on ophiuroids. Our feeding strategy graphical method reveled that K. coloratus and C. asperrimum were specialist predator, with a narrow niche width.

• Korean Journal of Ichthyology
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• v.23 no.2
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• pp.128-134
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• 2011

The feeding habits of scorpion fish, Sebastiscus marmoratus, were studied using 324 specimens collected in the coastal waters of Tongyeong, from January to December, 2009. The size of the specimens ranged from 9.8 to 30.1 cm in standard length (SL). S. marmoratusis was a piscivore that consumed mainly teleosts such as Engraulis japonicus, Clupea pallasi and gobid fishes. Of the fish species Engraulis japonicus was the most preferred prey. Its diet also includes shrimps and crabs. Hermit crabs, polychaetes, bivalves and euphausia were minor preys. Smaller individuals (<13 cm SL) fed mainly on shrimps, crabs and fishes. The proportion of shrimps and crabs decreased as body size increased, whereas the consumption of fishes gradually increased. Fishes accounted for almost stomach contents of larger individuals (more than 19 cm SL). Seasonal changes in the S. marmoratusis diet were significant. Fishes was most common prey during summer, autumn and winter, whereas crabs and shrimps were mainly consumed during spring.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.4
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• pp.227-233
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• 2013

A total of 25 species, 3,880 individuals and 3,145.1 g of fishes were collected by a surf net from the eelgrass bed in Minyang. Most fishes collected in the eelgrass bed belong mainly to small fish species or juveniles. The dominant fish species were Gymnogobius heptacanthus, Rudarius ercodes, Pholis nebulosa, Chaenogobius gulosus, and Gymnogobius castaneus which accounted for 89.1% of total number of individuals collected. The number of individuals and biomass were higher from June to September when the water temperature was high. However, both the number of individuals and species showed the lowest from January and February. Highest species diversity index (H') was observed in April, 2012.

• Journal of The Geomorphological Association of Korea
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• v.20 no.4
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• pp.71-83
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• 2013

In this study, the ecological presevation zone on uninhabited islands was established based on the setting of geomorphological landscape. The 14 uninhabited islands, which are scattered around the Goseong-gun and Tongyeong-si region have been surveyed on field. As a result of study, uninhabited island of Goseong-gun and Tongyeong-si was classified the absolute preservation areas(I), preservation areas(II), quasi-preservation areas(III), and a available areas(IV). These results evaluated 5 islands of Anjang Island(Maan-do), Bam Island, Saetgaekkeut, Dae Island(Juk-do) and Ttandok Island to be absolute preservation areas(I), the 8 islands of Mana Island, Yuk Island, Nabi Island, Sochi Island, Yongdu-do, Daeho-do, Jam-do, and Hwa-do to be preservation areas(II), the 1 island of Goeam Island to be quasipreservation areas(III). Those islands selected as absolute preservation areas and preservation areas have especially outstanding geomorphological landscape resources, and are expected to be able for use as natural study fields or as outdoor laboratories.

• 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.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.3
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• pp.422-428
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• 2019

Fish killing dinoflagellate Cochlodinium polykrikoides has been separated into four genetically differentiated subpopulations globally based on large-subunit (LSU) ribosomal RNA gene, and two subpopulations have been found in the South Sea, Korea. In this study, distributions of the East Asia and Philippines ribotypes were surveyed in the South Sea for 3 years (2014~2016) using quantitative real-time PCR (qPCR). The East Asia ribotype was detected in all sampling stations of the South Sea (Tongyeong~Wando) by 40~100% positives for 2014~2016, whereas the Philippines ribotype was detected in some areas of Tongyeong~Goheung by 1~2% positives for only 2016 when the Tsushima Warm Current (TWC) was particularly strengthened. These results indicate that the East Asia ribotype is the dominant subpopulation in the South Sea, also some of C. polykrikoides swimming cells might be transported from offshore to the South Sea via TWC.