• Korean Journal of Environment and Ecology
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• v.15 no.3
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• pp.224-229
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• 2001

The vascular plants in Chilsan islet were summarized as 84 taxi; 37 families, 74 genus, 71 species, 13 varieties. Evidence from the species distribution such as Cudrania tricuspidata and Mallotus japonicus, this islet belongs to the Southern province in phytogeographical point of view. The dominant species in the studied areas are in the follows; Both Carex boottiana and Artemisia carpillaris are in the Islet I, Carex boottiana for the Island II, Both Carex boottiuna and Mallotus japonicus fur the Island III. Clerodendron trichotomum for the Island IV. Both Miscanthus sinensis and Imperate cylindrie var. koenigii for the Island Ⅵ, respectively.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2001.04a
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• pp.129-132
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• 2001

• Korean Journal of Environment and Ecology
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• v.34 no.2
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• pp.99-105
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• 2020

Migratory birds use a variety of breeding and wintering sites, and it is particularly important to understand more information on breeding and feeding sites for the conservation and management of endangered species. Black-faced spoonbills (Platalea minor) are an international endangered species distributed in East Asia. The majority of black-faced spoonbills breed on uninhabited islets off the west coast of the Korean Peninsula during the breeding season, and they are distributed in East Asia such as Taiwan, Hong Kong, southern China, Japan, and Jeju island during the winter season. In this study, we used a wild animal location tracking system to analyze and compare home ranges of three black-faced spoonbills spending the post-fledging stage in Gujido islet in Incheon and Chilsando islet in Yeonggwang each in 2015. The tree black-faced spoonbills in Guji islet showed a home range in coastal areas in Hwanghaenam-do and Gangneung-gun. The home range size (mean±SD) was estimated to be 425.49±116.95 ㎢ using 100% MCP, 43.61±18.51 ㎢ using KDE 95%, and 7.46±3.68 ㎢using KDE 50%. The tree black-faced spoonbills in Chilsando islet showed a home range in the Baeksu tidal flat and the Buan Saemangeum area with a size of 99.38±55.29 ㎢ using 100% MCP, 19.87±6.05 ㎢ using KDE 95%, and 1.16±0.53 ㎢ using KDE 50%. The figured indicated that the tree black-faced spoonbills breeding in Gujido islet had a wider home range than those breeding in Chilsando islet. During the post-fledging stage, the home ranges of black-faced spoonbills were mostly breeding in mudflats. Therefore, it is necessary to minimize human intervention, such as the construction of roads and structures and the human access, to protect the habitats during the period.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.703-709
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• 2015

A breeding pair of the Black-faced Spoonbill Platalea minor was firstly recorded on Chilsando Islands, Younggwang, Jeollanamdo Province in 1991. Since the mid 2000s, breeding population on the breeding sites has gradually increased. This study was conducted to identify breeding status and nest site characteristics of the species from May to August, 2013 on Chilsando Islands. We recorded number of nests, length and width of the nest base, slope around the nests, nest materials, distances from the nearest nest, presence of nest cover and nesting area. In 2013 breeding season, 25 of 49 nests produced at least one successful fledging. A total of 55 youngs were successfully fledged and number of fledging per nest was 2.20 individuals. Nesting area was $77.8m^2$ and $93.4m^2$ for Sansando and Yuksando Islet, respectively. Soil and soil mixed with tree root were preferred for substrate of nest base over rock and Brassica napus was dominantly selected as nest materials by Black-faced Spoonbills. Nest characteristics of 22 nests in Sasando and Yuksando Islet varied $49.59{\pm}6.53cm$(mean${\pm}$SD) for length of nest base, $41.00{\pm}5.82cm$ for width of nest base, $20.85{\pm}9.96^{\circ}$ for slope above the nest, $34.09{\pm}17.75^{\circ}$ for slope below the nest and $130.82{\pm}84.17cm$ for distances from the nearest nest. Fifteen pairs (68.2%) occupied where nest cover existed. Nest cover were located in front of the nest for 5 pairs, back of the nest for 9 pairs and both front and back of the nest for 1 pair.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.4
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• pp.650-655
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• 2020

Chilsan-do Island, South Korea, has previously been identified as one of the biggest spawning sites of the small yellow croaker Larimichthys polyactis in the Yellow Sea. To determine whether Chilsan-do still serves as a spawning site for L. polyactis, three to five stations around Chilsan-do Island were surveyed for eggs from April to June (the main spawning season of L. polyactis) in 2019, using an RN80 net. For the first time, three L. polyactis eggs were identified at two stations, located just in front of Chilsan-do Island and between Chilsan-do and the coastline, only in May. The diameter of L. polyactis eggs (1.26-1.34 mm) was very similar to those of Collichthys niveatus (1.30-1.37 mm) and Setipinna tenuifilis (1.34-1.35 mm). During the survey period, the sea surface salinity remained constant (32.0-32.1 psu), but the sea surface temperature (SST) rapidly rose from 13.6-13.7℃ in April to 22.1℃ in May. Our findings suggest that L. polyactis still spawns near Chilsan-do Island today, but on a very small scale, and that changes in SST promote spawning of L. polyactis.

• Korean Journal of Environment and Ecology
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• v.35 no.2
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• pp.98-105
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• 2021

Understanding the migration patterns and habitats of juvenile birds during the post-fledging stage is very important for conservation and management of individuals. The Chinese Egret is an internationally protected species. During the wintering season, they inhabit South-East Asia, such as the Philippines, Malaysia, and Taiwan, and breed in China, Russia, and uninhabited islands on the west coast of Korea. IIn this study, we attached a GPS telemetry tracking device to six juvenile Chinese Egrets breeding on Chilsan Archipelago in 2018 and 2019 to identify habitats by analyzing the home range during the post-fledging stage in the summer season. The individual CE1801 moved north and then returned to the Yeonggwang Baeksu tidal flat area, and CE1802 and CE1803 migrated north and inhabited Taean-gun. In 2019, CE1901 showed a similar pattern to CE1801, and CE1902 migrated southward to the Wando-gun area, while CE1903 moved south to the Sinan-gun area then returned to the Yeonggwang Baeksu tidal flat area, showing KDE 50%. The study results confirmed that the Chinese Egret moved broadly around the flat tidal area on the west coast to find a stable habitat during the post-fledging stage. Efforts to protect the habitat, such as limiting the development of this area and restricting human access, are necessary.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.614-617
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• 2000

To get the maximum diffusion boundary of thermal effluent of Youngkwang Nuclear Power Plant, paths of TGPS Buoy and temperatures of surface water are obtained to 4 times at spring tide during 1 year. According to the paths of TGPS Buoy, the flumes of thermal effluent are moved about 12km from outlet to SW or WSW direction. After 3∼4 times of tidal period the waters are reached to Chilsan Island because the ebb flow is more predominant than the flood flow in this area. At the spring and fall season, a sudden drop of surface water temperature is detected around 5km radius from the outlet. At the summer season, it is measured about 10km. On the other hand the flumes are continuously cooled down by the atmosphere condition at winter season.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.2
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• pp.115-122
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• 2012

Frequency distribution of carapace width, relative growth, sex ratio and fecundity of blue crab Portunus trituberculatus in Younggwang adjacent water were investigated. A total number of individuals collected for this study were 658(Males : 305 and females : 353). Water temperature and salinity of the study areas varied from 5.9 to $27.3^{\circ}C$ and 28.1 to 31.6 psu, respectively. The carapace length-width and carapace width-weight relationship was calculated and the equations obtained are; For males; CL = 1.3652CW + 22.495($R^2$=0.741), $TW=0.0068CW^{2.4001}$($R^2$=0.749), For females; CL = 1.3073 CW + 25.684($R^2$=0.791), $TW=0.0061CW^{2.4231}$($R^2$=0.801). The sex ratios(Males : females) for blue crab were 0.86 : 1. The value of correlations coefficient between total weight and fecundity of the blue crabs was higher that of between carapace width and fecundity.

• Korean Journal of Ichthyology
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• v.36 no.1
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• pp.94-100
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• 2024

During ichthyoplankton survey in the southwestern sea of Korea, we collected six individuals of noodlefish larvae and juveniles between April and May 2023. They were identified as Neosalanx anderssoni by mitochondrial DNA cytochrome c oxidase subunit I or 16S ribosomal RNA sequences, and their external morphological traits were described for the first time. All six individuals have a slender and elongated body. When preflexion and flexion larval stages (10.24 mm notochord length, NL and 15.47 mm total length, TL, respectively), oval-shaped black melanophores were distributed in a row along the ventral side of the gut. However, when postflexion larval and juvenile stages (23.58~25.90 mm TL, and 29.20~31.26 mm TL, respectively), melanophores on the ventral side of the gut were disappeared, and dark spot-shaped melanophores appeared along the dorsal side of the gut in a single row. Also, from the postflexion larval stage (23.58 mm TL), two large black spots began to appear symmetrically on the caudal fin. Our results suggest that N. anderssoni may use coastal area as spawning and/or nursery ground unlike previous study (Kim and Park, 2002).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.2
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• pp.134-148
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• 2021

During the ichthyoplankton survey around the Chilsan Island (previously known as the biggest spawning ground of the Sciaenidae) in the southwestern sea of Korea from April to June in 2019 using ring nets, we collected a total of 12 individuals belonging to the family Sciaenidae. Using molecular methods, we identified five sciaenid species (Collichthys lucidus, Collichthys niveatus, Johnius grypotus, Nibea albiflora, and Pennahia argentata), and described and compared them on the basis of the preflexion larval stage. C. lucidus was well distinguished by the presence of occipital crests at preflexion stage. Although there were no occipital crests, preflexion larva of C. niveatus was distinguished by the absence of melanophore except for the upper part of the abdominal cavity. J. grypotus and N. albiflora were very similar morphologically, but were distinguished by myomere height (15.22-15.53% in J. grypotus vs. 11.66-12.78% in N. albiflora) in the percentage of notochord length, and eye diameter (32.58-33.37% in J. grypotus vs. 40.32-42.53% in N. albiflora) in the percentage of head length between specimens of similar size (J. grypotus: 3.22-3.23 mm, N. albiflora: 3.04-3.13 mm). P. argentata were distinguished by distribution of ventral caudal melanophore (one row of small spot in P. argentata vs. irregular patches on the central part of caudal in J. grypotus and N. albiflora). Comparative morphological studies using more diverse species must be conducted for more comprehensive understanding of the morphogenesis of Sciaenidae.