• Journal of Wetlands Research
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• v.7 no.2
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• pp.105-120
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• 2005

This study was carried out at Reed Marsh of Sihwa Lake from July 2003 to June 2004. We observed total(sum of maximum population) 5,752 individuals of 70 species including 12 species of ducks, 10 species of egrets, 6 species of wagtails and buntings, 4 species of eagles. The most dominant species was Spotbill Duck(Anas poecilorhyncha - 3,518 individuals, 61.16%), and other species were Mallard(Anas platyrhynchos - 540 individuals, 9.39%), Great Reed-Warbler(Acrocephalus arundinaceus - 217 individuals, 3.77%). Reed Marsh of Sihwa Lake were observed many kinds of protected species such as Great Bittern(Botaurus stellaris), Mandarin Duck(Aix galericulata), Chinese Sparrow Hawk (Accipiter soloensis), Eurasian Sparrow Hawk(Accipiter nisus), Japanese Buzzard(Buteo buteo), Hen Harrier(Circus cyaneus), Eurasian Hobby(Falco subbuteo), and Common Kestrel(Falco tinnunculus). Since the Reed Marsh of Sihwa Lake arrived many individuals of waterbird, crop damage by the waterbird occurred in the surrounding rice fields. It was an area adjacent to the reed marsh of sihwa lake such as Yoopori and Samhwari Bibongmyoun, Yamokri Maesongmyoun Hwaseong City. Bird of crop damage was ducks openly. The most species was Spot-billed Duck. Crop damage types by the Spot-billed Duck were grazing, used the grain up or lower in quality with step on the rice. Crop damage size was about 560bags of rice during the one month on August 2002. In 2003, After carrying out the various crop damage reduction countermeasures, which measured crop damage size in 2002's crop damage area. It happened about 152bags of rice during the two months from on August to September 2003. Migration routes of Spot-billed Duck were that it was migrated from up the sihwa lake to reed marsh. It took a rest at reed marsh and migrated the surrounding rice fields for the feeding action. In 2002, it was migrated direct from up the sihwa lake to in surrounding rice fields. But as environment of reed marsh was improved better than 2002, it was migrated to reed marsh because of reducing the energy attrition rate. Crop damage reduction countermeasures are get on ears to use explosion machine, searchlight, start-gun and patrol at regular intervals. Which was an effect short term. Indirect method is to make a feeding area of substitution at up the sihwa lake and reed marsh of sihwa lake.

• Korean Journal of Environment and Ecology
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• v.31 no.2
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• pp.135-151
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• 2017

Waterbirds were surveyed once a week from Oct. 2015 to Apr. 2016 to study the conditions of temperature of staying waterbirds on Wonju-Stream. The population staying on Wonju-Stream was in inverse proportion to the temperature change; birds increased as the temperature went down, and showed the highest peak counts on the 16th(27-Jan) survey, which was the lowest in temperature. decreasing as the temperature rose. The total population of Wonju River water birds increased with increasing freezing rate in proportion to the freezing rate of nearby reservoirs and tributaries. To clarify the relation of the numbers of the birds to temperature fluctuation, the correlation of the first period of wintering (1st~16th) and that of the later period(17th~27th) as well as the whole period was surveyed, based on the 16th which was the lowest in temperature. While most wintering waterbirds showed a negative correlation to the temperature, Egretta garzetta, Phalacrocorax carbo, and Ardea cinerea were positive in temperature relativity. Anas poecilorhyncha was in the highest relation to temperature fluctuation showing (7D/H3A(r=-0.960, P<0.000000001)) at 1-16 correlation(Cor.), with the whole wintering waterbird species showing the maximum correlation at 4D/LA in the every correlation(1~27Cor.(r=-0.942, P<0.01), 1~16Cor.(r=-0.947, P<0.01), 16~27Cor.(r=-0.958, P<0.01)). Each waterbird showed the correlation to the temperature variation(AT, HT, LT) and th duration(1D~7D) depending on the species differently. Most species demonstrated a bigger correlation to the lowest temperature rather than to the highest temperature. During the first half period of the wintering with the temperature falling it showed a high correlation to the temperature at the duration of 4D~7D, While it was for D1~D3 during the next half period.

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.516-522
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• 2014

This study was conducted to investigate the impact of the anthropogenic factors affecting distribution of the Red-crowned Crane and White-naped Crane wintering in Cheorwon, Korea. Especially, it was investigated that the impact power and its range of the anthropogenic effect to the feeding flock density in cranes due to the paved road, residential area, military facilities and greenhouse density. The Red-crowned Crane and the White-naped Crane showed the similar preference and sensitivity against anthropogenic factors, because correlation of feeding flock density of the Red-crowned Crane and White-naped Crane was similar in the same site. The feeding flock density of the cranes near the residential area was lower than that of area far from the area, and tended to increase within 2.5 km distance. The increasing tendencies of feeding flock density from military facilities and high traffic volume road were similar, but the density in military facilities increased within 0.8 km, and the density from high traffic volume road increased within 2 km. This results suggested that military facilities and the road with high traffic volume made significant influence on foraging densities to the certain range. As the distance from the road with low traffic volume increased, feeding flock density tended to decrease. The area near the low traffic volume road had high feeding flock density because remaining rice grains were preserved by intermittent disturbances in that area. If the density of greenhouse is lower than $40/km^2$, feeding flock density in the low greenhouses density area was higher than high greenhouses density area. However, there was no difference in the feeding flock density if the density of the green houses is higher than $40/km^2$.

• Journal of Environmental Impact Assessment
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• v.24 no.4
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• pp.301-316
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• 2015

The endangered species, The Red-crowned Crane and the White-naped Crane are vulnerable species to the disturbance for human beings. We examined the importance of CCZ for the cranes by comparing the crane's density in some CCZ-released areas, which are cranes' wintering site in Cheorwon. We also assessed influence of disturbance such as construction and greenhouses on core habitats of cranes. Our study results suggested that the construction and reclamation in the CCZ shrunk core habitat area while increasing core area of far from the construction and reclamation area. The CCZ has been set since March, 2011 and the number of greenhouse has rapidly increased after 2012. As the number and size of greenhouse in the area where designation of CCZ was cancelled increased, foraging area of cranes diminished. Although the area where designation of CCZ was cancelled seemed to have more human disturbance than CCZ, the foraging density of cranes did not decline and even that of white-naped cranes increased. This could be the influence of artificial food supply at their roosting site. In conclusion, if the area of CCZ decline continuously in the future, density of cranes would decrease.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.73-87
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• 2004

This study was carried out on Sihwa reclaimed area from January to December in 2003. We observed total 169,351 individuals of 70 species(22 species of waders, 9 species of egrets and 5 species of gulls). Waterbird population was the largest in March(95,465 individuals) and was the smallest from April to June(less than 7,000 individuals). The most dominant species was Pintail(Anas acuta: 58,627 individuals, 34.6%) and other species were Mallards(Anas platyrhynchos: 24.5%), Common Pochards(Aythya ferina: 13.8%), Black-tailed Gulls(Larus crassirostris: 6.1%), Spotbill Ducks(Anas poecilorhyncha: 5.0%) and Greater Scaups(Aythya marila: 2.69%). Sihwa reclaimed area supported many kinds of protected species such as Chinese egrets(Egretta eulophotes), Black-faced Spoonbills(Platalea minor), Eurasian Spoonbills(Platalea leucorodia), Mute Swans(Cygnus olor), Whooper Swans(Cygnus cygnus), and Eurasian Oystercatchers(Haematopus ostralegus). They foraged at waterside of Sihwa lake and rested at reclaimed area. Particularly, Eurasian Oystercatchers bred in habitats with Salicornia herbacea and Suaeda japonica. Reclamation of mud flats and construction of roads, transmission towers and tide embankments disturbed waterbirds in breeding and foraging. We suggest that waterbirds are protected in different action plans according to their status such as breeding, passaging and wintering birds. Maintaining of waterside and swamps in Sihwa reclaimed area will be useful for breeding waterbirds. It is needed to make a protect zone for ecological connecting belt from Oeji isarea, Hyeong isarea, Eum isarea to upper channel on Sihwa lake.

• Journal of Wetlands Research
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• v.19 no.2
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• pp.223-229
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• 2017

This study analyzed the relationship between environmental factors and the temporal changes of the bird populations during the every January from 1999 to 2016 (18 years) in Donglim reservoir. 'Winter Waterbird Census of Korea' data by National Institute of Biological Resources were used for the bird population data, and principal component analysis and cluster analysis were used to analyze the changes of annual population. The average temperature of January and the average storage rate of the reservoir were used as environmental factors. According to the results of the study, the population changes in the study area can be explained by the increase and decrease of two water bird groups and a mountain bird group. The average temperature of the years when the population of water bird groups increased was more than $1.4^{\circ}C$ in comparison with the year when mountain birds increased. On the other hand, the influence of the water content was not clear. The visiting of Baikal Teal affected by temperature was a factor affecting the other group of water bird and a mountain bird group. The results of this study suggest that the temperature change affects the global spatial distribution of birds and the migration of large population species such as Baikal Teal affects species composition and populations of birds at local scale. Therefore, understanding of environmental changes at large scale and spatial distribution of species and flock contributes to understand the temporal variation of the bird population at regional or local scales.

• Korean Journal of Environment and Ecology
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• v.17 no.3
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• pp.295-303
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• 2003

The tidal flat area of south and west coast consists of 2.4% of total land area of Korea. About 83% of tidal flat is located at the west coast, and the remaining tidal flat is located at the south coast. This tidal flat is also divided for administrative regions which are Gyeonggi Province(35.1%), Chungnam Province(12.7%) Jeonbuk Province(4.7%), Jeonnam Province(44.0%) and Gyeongnam Province(3.5%). The tidal flat of west coast of Korea is one of the most important stopover site for shorebirds on the East Asia-Australia Flyway. The tidal flat is used for feeding and resting place by migratory shorebirds. Generally, waterbirds including migratory shorebirds are considered as key species to show the superiority of wetland. By the criteria of Lamsar Convention in the basis of waterbird, at least 14 coastal wetlands in Korea have to be internationally important wetlands. The factors to affect the distribution of shorebirds at the certain tidal flat are closely related with 1) the distribution of benthic invertebrates, potential prey of shorebirds 2) the availability of roosting site 3) the size of tidal flat 4) the intensity of human disturbance. In this paper, we summarized the regional status of tidal flat of Korea and its conservation methods related with migratory waterbirds.

• Korean Journal of Ecology and Environment
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• v.47 no.4
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• pp.282-291
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• 2014

This study was conducted to make distribution model of the Red-crowned Crane and the White-naped Crane according to the anthropogenic and natural factors affecting distribution of crane in Cheorwon, Korea. It was investigated that the impact power and its range of the indirect anthropogenic influence to feeding flock density in cranes from the road, residential area, military facilities, civilian control zone (CCZ), greenhouse and natural influence such as roosting site and available feeding area. Available feeding area is the most important factor for the crane's feeding site selection. The feeding flock density of the cranes near the residential area was lower than that of area far from the area, and tended to increase within 2.5 km distance. The increasing tendencies of feeding flock density from military facilities and high traffic volume road were similar, but the density in military facilities increased within 800 m, and the density from high traffic volume road increased within 2 km. These results suggested that residential area, military facilities and the road with high traffic volume had significant effect on foraging densities to the certain range. As the distance from the road with low traffic volume and roosting site increased, feeding flock density tended to decrease. The density of Red-crowned crane and White-naped crane inside the CCZ were respectively higher than those of outside the CCZ, especially for the Red-crowned crane. As a result, density of Red crowned cranes inside the CCZ was 5.2 times higher than that of outside, while that of white-naped cranes was 2.2 times bigger. If the density of greenhouse is lower than $40km^{-2}$, crane's feeding flock density in the low greenhouses density area was higher than that of high greenhouses density area. However, there was no difference in the feeding flock density if the density of the green houses is higher than $40km^{-2}$. The model for the Red-crowned Crane was related with available feeding area, distance from residential area, civilian control zone and distance from high traffic road. The model of the White-naped Crane was related with available feeding area, distance from roosting site and distance from lake. Finally, the estimated feeding flock density of cranes significantly correlated with density model according to the natural and anthropogenic factors.

• 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.

• Journal of Environmental Impact Assessment
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• v.29 no.1
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• pp.1-7
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• 2020

This study aims to evaluate the effect of artificial facilities constructed afterthe release of the civilian controlled zone (CCZ) in Cheorwon on the inhabitation of cranes. The study site was released from the CCZ in 2012, and several barns have been built since 2017. The average number of Red-crowned Cranes was 9.3±4.3 individuals (±Standard Deviation) in the period before the release of the CCZ from 2009 to 2012, and it decreased by ca. one third of Red-crowned Crane's average individuals were showing 3.5±0.5 individuals after release. The average number of White-naped Cranes also appeared to be decreased by ca. 90% from 63.3±24.6 to 6.0±6.0 individuals. This results suggest that the construction of greenhouses and barns after the releasing of the CCZ affected the decrease of the population of these two crane species. In the case of Red-crowned Crane, the core area tended to move away from the area where barns were built. However, the distribution range of Red-crowned Cranes did not change significantly we expected because the study area was not their favorite place since 2012 when the area was released from the CCZ. The density of the White-naped Crane was relatively high even in the area where greenhouses were built, but after 2017 when the barn was built intensively, core habitat of crane became shrink and fragmented. These results suggest that both Red-crowned Cranes and White-naped Cranes response sensitively against habitat change due to the construction of barns. Since the release of the CCZ, the construction of the greenhouse has been influenced on the distribution of cranes, but subsequently, the construction of the barn seems to have caused a bigger change in their core habitat because the passage of people to barns is more frequent than the greenhouses.