• Journal of Aquaculture
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• v.21 no.4
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• pp.278-284
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• 2008

Artificially-produced juvenile black sea bream Acanthopagrus schlegeli (total length $8.3{\pm}1.0\;cm$, body weight $11.2{\pm}4.2\;g$) were released in eelgrass, Zostera marina bed and their initial food organism and changes of body compositions were investigated for one month after release. Predation rates in fish sampled on 1st and 3rd days were 79%, increased up to 100% on 7th and 10th days, and then decreased on 30th days as 75%. Major prey organisms was composed of mainly Amphipoda and Gastropoda. Ratio of Amphipoda and Gastropoda in stomach were highest in fish sampled on 15th and 1st days after release, respectively. Crustacea and Algae were maintained about 20% during a sampling period. Visceral weight index (VWI) offish sampled 20th and 30th after release were significantly higher than that of initial. Carcass crude protein and lipid contents of released fish were showed significantly decreasing; however carcass n-3 HUFA composition was showed increasing tendency with the passage of time after release. Eelgrass bed was supposed to be helpful for the released fish to adjust their feeding habits and biochemical metabolism to the natural environment within a short period after release.

• Korean Journal of Ichthyology
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• v.9 no.2
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• pp.202-220
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• 1997

A total of 57 species of fish species was collected by a trawl from the eelgrass bed in Kwangyang Bay. The dominant species were Pholis nebulosa, Syngnathus schlegeli, Leiognathus nuchalis, Pseudoblennius cottoides, Sebastes inermis, Favonigobius gymnauchen, which accounted for 69.9% of the total numbers of fish collected. Fish collected in the study area were primarily small fish species or early juveniles of large fish species. Only about 10% of fishes which were collected in the eelgrass bed exceeded 15cm in standard length. Seasonal variations in both species composition and abundance were major characteristics in the study area. The peak abundance occurred in spring, while the number of species was the highest in fall. However, both the number of species and abundance of fishes showed the lowest values in winter. High species diversity indices were observed in fall. Temperature, eelgrass standing crop and abundance of food organisms influenced seasonal changes of the fish community in the study area. More abundant and more diverse fishes were collected during nighttime than daytime.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.573-574
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• 2002

• Korean Journal of Ichthyology
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• v.9 no.2
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• pp.221-227
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• 1997

Feeding habits of Leiognathus nuchalis collected from the eelgrass bed in Kwangyang Bay from January 1994 to December 1994 were studied. Leiognathus nuchalis was a carnivore which mainly consumed copepods and crab larvae. Its diets included small quantities of polychaetes, amphipods, mysids, caridean shrimps. It showed ontogenetic changes in feeding habits. In an initial feeding stage, copepods were major food organisms. However, crab larvae and polychaetes were heavily selected with increasing fish size. Although copepods and crab larvae were major prey organisms for all seasons, the relative proportion of these two food items changed with season.

• ALGAE
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• v.22 no.2
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• pp.141-146
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• 2007

Seagrass bed is an important component in coastal and estuarine ecosystems, providing food and habitats to a wide variety of marine organisms. Recently, seagrass coverage has declined significantly due to anthropogenic impacts such as cultural eutrophication and reclamation, and thus efforts are under way to prevent further losses and restore disturbed seagrass habitats worldwide. Seagrass transplantation techniques for habitat restoration include vegetative and seed-based methods. Seagrass seeds can be collected easily, and sowing seeds is an economically effective method for large-scale restoration. However, large numbers of seed can be lost by seed predation and physical disturbance in the planting areas. In the present study, Zostera marina seeds were coated with loess to reduce seed loss by predation and sweeping away by the water currents, and germination rates of coated seeds and seedling growth were examined to assess the feasibility of the seed-coating method for large-scale restoration. Germination rate of the coated seeds with loess was significantly higher than that of the uncoated seeds. Additionally, seedling growths were not significantly different between the coated and the uncoated seeds. These results suggest that coating of eelgrass seeds with loess enhances success of seed germintion with no harmful effects on seedling growth. Therefore, the seed coating method using loess may be an effective and applicable seedbased transplanting technique for large-scale restoration.

• 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 Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.532-542
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• 1997

Seasonal variation of a shrimp community in the eelgrass (Zostera marina) bed in Kwangyang Bay, Korea was studied based on the monthly collected samples through a year of 1994. The shrimp community in the eelgrassbed was composed of 26 species of shrimps representing 6 families. The community was dominated by Heptacarpus pandaloides, Crangon affinis, Eualus leptognathus, Latreutes acicularis, Heptacarpus rectirostris, Heptacarpus geniculatus, and Latreutes laminirostris. Most of species were the small-sized species with carapace length smaller than 25 mm. The peak abundance occurred in the late winter and spring and low abundances in autumn. More than 10 species were collected every month except lull (8 species). Species diversity indices showed that the shrimp species were more diverse during the late summer, and lesser during the late autumn. Predominance of Crangon affinis in the late autumn caused such a low diversity. The shrimps in the study area could be grouped into three groups on the basis of their occurrence patterns: resident species, seasonal species, and temporary species. More abundant and more diverse shrimps were collected during nighttime than daytime.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.1
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• pp.9-16
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• 2013

The growth and production of Aulichthys japonicus (6.70~15.32 cm TL) were investigated in an eelgrass bed of Dongdae Bay, Korea throughout 2006. A total 888 A. japonicus were collected with a small beam trawl. Growth in fish total length was expressed by the von Bertalanffy's growth equation as: $L_t=24.8257(1-e^{-0.5583(t+0.4816)})$. The densities, biomass, daily, annual production, and P/B ratio were $0.01{\pm}0.009/m^{-2}$, $0.17{\pm}0.16g/m^2$, $0.00006{\pm}0.00006g$ AFDW/$m^2$/day, 0.02g AFDW/$m^2$/yr, and 0.12, respectively. Monthly variation in production of A. japonicus was large; the peak occurred at July, September and November 2006 (0.000182, 0.000127 and 0.000123 g AFDW/$m^2$/day), where as the lowest value was 0.000003g AFDW/$m^2$/day at April and May 2006. Monthly change in production of A. japonicus was positive correlated with number of individuals, biomass and growth rate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.105-109
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• 2002

Seasonal variations of species composition and density of caprellids was accomplished in eelgrass beds around Daedo Island, a south coast of Korea. Sampling was performed monthly using an epifaunal sampler at two stations from June 1996 to May 1997, Caprellids were comprised of 6 species belong to a family Caprellidae, Mean density was 402 ind./$m^2$. The numerically-dominant species were Caprella tsugarensis (216 ind./$m^2$) and C. kroeyeri (129 ind./$m^2$). High density was occurred in the early summer, and lows in autumn and winter. The density of caprellids was correlated with the biomass of the eelgrass. Predation pressure by fish was also correlated with the density of caprellids in spring.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.372-379
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• 1998

Feeding habits of Favonigobius gymnauchen collected from the eelgrass bed in Kwangyang Bay from January 1994 to December 1994 were studied. Favonigobius gymnauchen was a carnivore which consumed mainly gammarid amphipods, polychaetes, crabs and copepods. Its diets included minor Quantities of gastropods, tanaids and isopods. It showed ontogenetic changes in feeding habits. Small individuals (1$\~$2 cm) fed mainly on gammarid amphipods, polychaetes, and copepods. While the portion of the stomach contents attributable to polychaetes and crabs increased steadily with incensing fish size, consumption of copepods decreased progressively. Gammarid amphipods were the most selected prey item for all size classes. Although gammarid amphipods, polychaetes, crabs and copepods were major prey organisms for all seasons, the relative proportion of these food items changed with season. Consumption of copepods was relatively high in spring and fall and consumption of gammarid amphipods, polychaetes and crabs was relatively high in summer.