• Journal of Ecology and Environment
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• 제34권4호
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• pp.357-363
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• 2011

To examine factors affecting feeding efficiency of grey herons (Ardea cinerea), the foraging behavior was studied at a reservoir in Asan city, Chungcheongnam-do, South Korea during the breeding seasons (from April to July) of 2006 and 2007. Four factors (age of foraging birds, time of day, breeding stage, and microhabitat type) were analyzed. Adults were more efficient foragers than recently fledged juveniles, and they had a higher success rate than juveniles. About half of the adults caught large prey, whereas most juveniles caught only small prey. Adult grey herons had different feeding efficiency according to the breeding stage. Pecking and capture rates were high during the late period (fledging stage), and biomass intake rates were high during the early (incubating stage) and late periods. However, time of day had no significant effect on foraging activity of adult grey herons. Feeding activities of adult grey herons also showed significant variation among microhabitat types. Pecking and capture rates were higher in the submerged plants area, but capture success rate and biomass intake rate were not different according to microhabitat type.

• 환경영향평가
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• 제26권5호
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• pp.315-330
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• 2017

본 연구는 도서지역에 침입한 굴토끼(Oryctolagus cuniculus)의 서식양상과 섭식 영향을 밝혀 효과적인 관리에 필요한 기초자료를 제공하고자 수행되었다. 조사 대상지인 범섬과 까막섬은 도입식물의 식재, 답압, 경작활동 등 인위적 간섭에 의해 교란된 이차식생 유형이다. 범섬에 정착한 굴토끼는 벌채지를 중심으로 높은 흔적밀도를 보였고, 까막섬에 정착한 굴토끼는 낙엽활엽수림대를 중심으로 높은 흔적밀도를 나타내었다. 조사지역에서 확인된 굴토끼 섭식 가해 식물은 총 12과 17분류군으로 확인되었다. 범섬에서는 총 9과 11분류군의 섭식 가해 식물이 확인되었고, 먹이 가용 식물이 대부분 소실된 까막섬에서는 총 5과 6분류군의 섭식 가해 식물이 확인되었다. 범섬의 식생지수는 도서 전체 면적의 약 6.6% 감소하였고, 까막섬의 식생지수는 전체 도서지역에서 감소하였다. 까막섬은 Enhanced Vegetation Index가 -0.008unit/yr 이상 감소하는 지역이 전체의 5.2%였으며, -0.008~-0.006unit/yr으로 감소하는 지역은 전체의 13.32%로 확인되어 심각한 식생 교란과 생물다양성 손실이 예상되므로 도서생태계의 보전과 복원을 위한 즉각적인 관리가 필요하다.

• 환경생물
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• 제37권4호
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• pp.483-492
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• 2019

번식기 유부도 일대의 조수 경계부에서는 검은머리물떼새(Haematopus ostralegus osculans) 성체와 미성체가 한데 모여 복족류(서해비단고둥, Umbonium thomasi)와 이매패류를 섭식하는 것이 관찰된다. 본 연구는 성체와 미성체 간의 섭식 능력에 차이가 있는지 알아보고자 해당 먹이원을 섭식하는 개체들의 행동을 영상으로 녹화한 후 성체와 미성체로 구분하여 단위 시간당 걸음수, 먹이원 탐색시도횟수 및 탐색방법 구성비율, 섭식성공횟수, 조작시간, 머리 들어 올리기횟수를 비교하였다. 서해비단고둥을 섭식할 때 먹이원 탐색방법의 구성 비율, 이매패류를 섭식할 때 먹이원 탐색시도횟수와 머리 들어올리기횟수에서 유의한 차이를 나타냈으나, 단위 시간당 걸음수, 탐색시도횟수, 섭식성공횟수는 차이가 없었다. 결과적으로 번식기 유부도 일대에 서식하는 검은머리물떼새 미성체가 성체에 비해 비록 열세이고, 먹이원의 위치를 파악하는 능력이 부족하지만, 전반적인 섭식 능력은 성체와 유사한 수준임을 의미한다. 월동기간 동안 고도의 섭식 능력을 갖추어야 섭식이 가능한 이매패류를 지속적으로 섭식한 것에 기인한 것으로 판단된다.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제3권3호
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• pp.165-171
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• 2022

The Chinese crested tern (Thalasseus bersteini) is one of the most globally endangered species, listed as "Critically Endangered (CE)" on the IUCN Red List, with only approximately 30-49 individuals surviving in the wild. Chinese crested terns were discovered to breed in South Korea for the first time in 2016 while conducting a census on uninhabited islands. The Ministry of Environment has declared the breeding habitat of the Chinese crested terns as "Specified Island" to protect this CE species. However, brown rats (Rattus norvegicus) inhabiting the breeding grounds of the Chinese crested terns and Black-tailed gulls may potentially pose a threat to the breeding of these avian species. Therefore, we conducted a study on the feeding behavior of brown rats involving stable isotope analysis to determine their food sources. Fecal analysis showed that brown rats mainly fed on plants, whereas they scarcely fed on animals, such as insects. In addition, the stable isotope analysis showed that the δ¹³C values of brown rats, insects, and Indian goosegrasses were approximately -16 to -11‰, whereas the δ¹³C value of Chinese crested terns that obtained their food from the marine ecosystem was approximately -22 to -18‰. Hence, we conclude that the source of carbon for brown rats on this island is the terrestrial ecosystem. We ruled out the possibility of any direct prey-predator interaction between the brown rat and the Chinese crested tern or Black-tailed gull.

• Animal Systematics, Evolution and Diversity
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• 제29권2호
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• pp.99-114
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• 2013

Phylogeographic and feeding ecological studies of seven terrestrial mustelid species (Carnivora, Mustelidae), the Japanese marten Martes melampus, the sable Martes zibellina, the Japanese badger Meles anakuma, the ermine or the stoat Mustela erminea, the Japanese weasel Mustela itatsi, the least weasel Mustela nivalis, and the Siberian weasel Mustela sibirica, representing four biogeographic patterns in the Japanese archipelagos (Hokkaido, Honshu-Shikoku-Kyushu, Tsushima, and Hokkaido-Honshu), were reviewed in order to clarify causes for the faunal assemblage processes of those mustelid species in Japan. Here, three main constraints were extracted as important factors on the mustelid assemblage. First, fundamental evolutionary differences maintained by niche conservatism in each ecologically diversified lineage ("evolutionary constraint") would enable the species to co-occur without any major problem (coexistence among Martes, Meles, and Mustela species). Second, "ecological constraints" would force two closely related species to be allopatric by competitive exclusion (Mu. itatsi and Mu. sibirica) or to be sympatric by resource partitions (Mu. erminea and Mu. nivalis). Third and most importantly, "geological constraints" would allow specific species to be embraced by a particular geographic region, primarily deciding which species co-occurs. The allopatric distribution of two Martes species in Japan would have been established by the strong effect of the geological separation in Tsugaru Strait. Elucidating both phylogeny and ecology of co-existing species in a community assemblage is important to know which species possess distinct lineage and which ecological traits are adapted to local environments, fulfilling the requirement of the field of conservation biology that endemism and adaptation should both be considered. The Japanese archipelagos would, therefore, provide valuable insight into the conservation for small carnivoran species.

• Journal of Nutrition and Health
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• 제54권5호
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• pp.474-488
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• 2021

Purpose: Malnutrition in children with cerebral palsy (CP) is a significant factor affecting their adequate growth and development. This study aimed at conducting surveys and evaluating the dietary intake of children with CP according to their BMI classification and to thereby highlight the dietary factors affecting the nutritional status of these children. Methods: A total of 16 children were enrolled between the age of four and twelve. These subjects were further classified into three groups, namely underweight, normal and obese, with 6, 8, and 2 children in each group, respectively. The general characteristics, motor disturbances, body composition, feeding problems, eating habits, nutritional intake, dietary variety, and food frequency for children with CP were evaluated. Results: It was observed that motor disturbances tended to increase in underweight children with CP. A significant decrease (p < 0.05) in disturbances related to oral feeding was observed with an increase in obesity. The pattern of eating habits revealed that subjects in the underweight group consumed unbalanced meals, while those in the obese group tended to consume larger meals at a faster pace. The feeding disturbance data revealed that those in the underweight group could not prepare their meals while the obese group had the problem of overeating and consuming an unbalanced diet (p < 0.05). Conclusion: It is necessary for both children with CP, who have a high degree of disability, and their caregivers to take lessons on adequate nutrient intake to prevent malnutrition. Moreover, it is necessary for the caregivers and children with CP having a low degree of disability to take lessons on providing and consuming a balanced diet and to focus on the intake of sufficient calcium in order to prevent obesity.

• 생태와환경
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• 제40권2호
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• pp.337-345
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• 2007

2004년부터 2005년에 걸쳐 옥정호 육봉형 은어(Plecoglossus altivelis)의 성장에 따른 식성 및 섭식기관의 변화를 조사하였다. 호소에 서식하는 체장 $25{\sim}40$ mm의 후기자어는 요각류, 물벼룩류 및 윤충류를 주로 섭식하였고, 체장 $50{\sim}60$ mm의 치어는 파리목의 깔다구류, 요각류 및 물벼룩류를 주로 섭식하였다. 반면에 추령천에 소상한 $60{\sim}70$ mm의 치어는 동물성 먹이와 조류를 같이 섭식하였으며, 70mm 이상의 미성어는 Synedra, Cymbella, Navicula 및 Pinnularia와 같은 부착 조류를 주로 섭식하였다. 또한 성장 및 먹이생물과 관련하여 이(teeth)와 위 (stomach)의 형태도 바뀌었다.

• Journal of Ecology and Environment
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• 제29권2호
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• pp.165-169
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• 2006

As a Biodiversity Management Plan in S. Korea, barley fields are being prepared for the wintering migratory birds. However, the effectiveness of barley fields as a feeding habitat has not been evaluated. In 2003/04 wintering period, we installed exclosures in the barley fields to evaluate the waterfowl grazing effectiveness. Approximately 8,000 waterfowls used the Dongup Reservoir System and utilized the barley fields during the daytime. The white-fronted goose Anser albifrons occupied more than 90% of the all barley-feeding waterfowls. Waterfowls significantly impacted to the shoot density and biomass of barley. In the closed plot, barley shoot density gradually increased to $267{\pm}27/m^2$ in January, 2004. Shoot density in open plots (site 1) declined sharply from.15 December ($189{\pm}18/m^2$) to 5 January 2004 ($25{\pm}11/m^2$). However, barley shoot density in open plots (site 2) was stable in January 2004 because of human disturbances. The changes in barley biomass and shoot density showed similar trend in both open and closed plot. From the exclosure experiment, it was clear that barley fields were important feeding habitat for wintering waterfowls in this area. Further, human disturbances such as noise from traffic and other human activities (farming and hiking) had significant impact on waterfowls' grazing activity. Collectively, winter barley fields were effective for waterfowl feeding, but the location of barley fields should be carefully selected for the maximum utilization of the barley feeding.

• 생태와환경
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• 제47권4호
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• pp.282-291
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• 2014

본 연구에서는 두루미류의 개체군 및 서식밀도에 영향을 주는 요인 중 자연적 요인과 함께, 인간에 의한 직 간접적인 교란의 영향에 의한 서식분포모델을 도출하고자 하였다. 대상지역은 강원도 철원군의 민간인통제지역이며, 2009년부터 2014년까지 매년 1월의 두루미와 재두루미의 분포를 대상으로 하였다. 두루미류의 서식밀도는 거주지, 군사시설, 통행량이 빈번한 도로와 가까울수록 서식밀도가 감소하였고, 거리가 멀어질수록 서식밀도는 증가하였다. 통행량이 적은 도로, 잠자리와의 거리 및 비닐하우스의 밀도가 증가할수록 두루미류의 서식밀도는 감소하는 경향을 보였다. 또한, 두루미류의 서식밀도는 민간인통제지역 외부보다 내부의 밀도가 높게 나타났다. 전체 요인을 이용해 단계적 진입을 통한 회귀분석의 결과, 두루미는 $3.4{\times}$AV_FE (이용이 가능한 농경지의 면적 ha)+$1.27{\times}$N_RES (거주지와의 거리 km)-$0.54{\times}$CCZ_0 (민통선 내:0-외:1)+$0.4{\times}$N_HTR (통행량이 많은 도로와의 거리)-1.40이었다. 재두루미는 $9.0{\times}$AV_FE-$5.47{\times}$N_LTR (통행량이 낮은 도로와의 거리 km)+$0.49{\times}$N_Lake (저수지와의 거리 km)+1.02이었다. 두루미와 재두루미 모두 공통적으로 이용 가능한 농경지의 면적이 중요하였고, 두루미에서는 거주지와의 거리 및 통행량이 많은 도로와의 거리가, 재두루미에서는 통행량이 낮은 도로와의 거리가 중요한 요인으로 나타났다. 두 가지 종 모두에서 모델에 의한 추정값과 실제 분포를 이용한 밀도 사이에 유의미한 상관관계가 나타났다.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제4권3호
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• pp.104-114
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• 2023

In this study, the distribution, bait preference, hosts, symbionts, habitat status, and cytochrome c oxidase subunit-I sequences of the ant Linepithema humile were analyzed. This species habitat comprised approximately 1.5 km along stone crevices, flower gardens, roadsides, and container yards in the vicinity of Busan station, Korea. Feeding activity of this species was confirmed in 9 species of 7 families of plants. Which was approximately 14% of total flora (63 species of 37 families) in the studied area. Particularly, it was observed that Dendranthema indicum and Camellia japonica were the most frequently visited. Further, we verified that they interacted with four species of aphids. We identified 22 species of ants (17 genera, 4 subfamilies) inhabiting the Busan station area, including L. humile, Tetramorium tsushimae, Nylanderia flavipes and the alien species Paratrechina longicornis. In areas where L. humile was the dominant species, the habitat of local native ants was reduced by approximately 30%. Bait preference was ranked in the following order: jelly, water with glucose (25%), and yogurt, with the highest preference for baits containing sugar and protein. The 630-bp cytochrome c oxidase subunit-I sequences of the local L. humile populations were 99% identical to those of L. humile in the National Center for Biotechnology Information database, and the Argentine ants that invaded Korea had a sequence identical to that of other invasive populations from China, Japan, and New Zealand. As L. humile rapidly increases due to domestic adaptation, continuous monitoring and control strategy for eradication are needed to protect domestic biodiversity.