• Journal of Ecology and Environment
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• 제43권3호
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• pp.282-288
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• 2019

We investigated the changes in the population size and inter-specific space usage for breeding in mixed breeding sites of the great cormorant (Phalacrocorax carbo), grey heron (Ardea cinerea), great egret (Ardea alba modesta) and intermediate egret (Egretta intermedia) in Gammul-myeon, Goesan-gun, Chungcheongbuk-do, South Korea, in 2016-2017. These species bred in two adjacent habitats (site A and site B). The number of breeding pairs of all species and the size of the breeding area at site B increased in 2017. In 2017, great cormorants at site B occupied the breeding sites previously occupied by the other species in 2016, while the grey heron and great egret occupied the sites around the great cormorant breeding site. The heights of nest trees and nests of great cormorant and grey heron did not differ temporally, but these heights in site B were significantly higher than those in site A for great cormorants. For great egrets, these greatly decreased in site B in 2017. Thus, the great cormorant either moved to favourable nest sites for breeding success or selected nest sites used by the herons in the previous year. Further studies of these two possibilities are necessary.

• Journal of Crop Science and Biotechnology
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• 제11권3호
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• pp.193-198
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• 2008

To develop a natural re-seeding technology, the optimum soil incorporation time of Chinese milk vetch(CMV) plant residues, seed persistence in soil, biomass production and subsequent rice yield were determined from 2005 to 2007 in rice with CMV green manure in southern Korea. Generally, insufficient seedling stand was regenerated with CMV incorporation to the soil at 20 and 25 days after flowering(DAF), while high regeneration of greater than 400 seedlings per $m^2$ was observed at 35 and 40 DAF. High re-seeding stand of CMV incorporated at 35 DAF or later was related with high seed viability and heavy seed weight. Appreciable number of CMV seeds remained 4 month after burial in soil and a good number of CMV seedlings regenerated from this seed bank at rice harvest time in the fall. Based on the relationships among re-seeding number of CMV plants, seed weight and seed viability, CMV plants should be incorporated into the soil 35 DAF(May 30) or later when CMV seeds were sufficiently matured. The natural re-seeding stand for the 3-year trials was stable ranging from 437 to 700 plants per $m^2$ and the biomass production was sufficient to supply nitrogen for rice growth. The use of re-seeding CMV plant can produce similar rice yield like that of rice without CMV green manure.

• 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.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제2권4호
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• pp.279-284
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• 2021

The dung beetle, Gymnopleurus mopsus (Coleoptera: Scarabaeidae), is one of endangered species in South Korea. It was last recorded in 1971. To restore this species, we introduced G. mopsus populations from eastern and southern regions of Mongolia in July 2019 and August 2019, respectively. One of the main tasks for the restoration of endangered insects is to develop breeding techniques to eventually incorporate these insects into the restoration system. In a series of laboratory experiments, we investigated effects of short-term hibernation periods on life-history traits of G. mopsus. Adult G. mopsus that had hibernated for 30, 60, and 90 days had lower survival rates than adults that had hibernated for 120 days. We also compared developmental time of these four experimental groups and found a significant difference in the egg - phase. However, the duration of hibernation did not affect the fecundity, brood-ball size, or body size of F1 adults. Follow-up studies are currently being conducted to further investigate the effect of a short-term hibernation period on population growth of G. mopsus under laboratory conditions.

• Journal of Ecology and Environment
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• 제29권1호
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• pp.69-74
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• 2006

The captive breeding biology of the Oriental white stork (Ciconia boyciana) was studied over 3 breeding periods. Both the male and female participated in nest building, but the male started to build the nest earlier and spent much time. Time used to build the nest was steadily increased to the egg laying. The copulations were observed $30{\pm}10.53$ (n=3) times in a breeding period. Both male and female incubated their eggs but the female spent more time than the male did. The chicks were hatched $32{\pm}1.29$ (n=6) days after egg laying. Not only the male but also the female took part in the rearing chicks. The male spent more time than the female as chicks grew. The results of this study are useful to assess the ecological soundness of the breeding pair and facilitate the breeding environment in captive breeding of the Oriental white stork.

• 한국환경생태학회지
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• 제22권3호
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• pp.332-337
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• 2008

본 연구는 남산과 광릉의 침엽수림을 대상으로 번식기 조류 군집의 특성을 파악하기 위해 2006년 4월부터 8월까지의 기간 동안 실시되었다. 두 지역에서 각각 10ha 크기의 고정조사구를 설치하고 세력권 도식법을 이용해서 번식기 조류군집의 특성을 조사하였다. 남산과 광릉의 침엽수림 지역에 생육하고 있는 수목의 흉고직경 분포와 엽층의 수직적 구조는 큰 차이가 있는 것으로 나타났다. 두 지역의 번식기 조류 군집 조사 결과, 번식 종수 및 번식 쌍수, 번식 밀도, 종 다양도 지수 등이 모두 광릉 지역에서 높았다. 번식기 조류 군집의 길드 구조에서도 두 지역 간에 차이가 있는 것으로 나타났다. 조류 군집의 다양성 및 특성이 두 지역 간에 차이가 있는 것은 두 지역의 서식 환경과 밀접한 관련이 있을 것으로 판단된다. 남산과 같이 훼손된 생태계 내에서 조류 군집의 보호 및 관리를 위해서는 산림 환경 구조의 다양성을 확보 할 수 있도록 산림의 엽층 피도량을 증가시키고 또한 구조적, 기능적으로 다양한 구조의 환경으로 유도하는 것이 필요할 것으로 판단된다.

• 한국환경생태학회:학술대회논문집
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• 한국환경생태학회 2006년도 임시총회 및 학술논문발표회
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• pp.98-102
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• 2006

We studied the behavior of black vultures breeding in Erdenesant, Mongolia through time budget observation. We observed a pair of black vulture for 115 days from April 30 to August 22, 2005, of which 15 days were before hatching and 100 days of brood rearing. The egg hatched on May $14^{th}$. Incubation was done by both a male and female vultures, but the period covered by the male vulture(56.82%) was longer than that by the female one(34.62%). In the early days of brood rearing, time spent by the female vulture at the nest took 54.9 % and it was 19.27% for the male. In the middle of brood rearing period, just inaction and preening were noticed, as they watched their chicks for a long time without sheltering chick under the parent's body. Late brood rearing period was characterized by less chick care and adults mostly stayed in the nest only when to feed the chicks. During breeding time, both the male and the female vulture fed only the chicks and did not give food to each other. During rearing period, the male vulture fed the chick more often than female.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제3권3호
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• pp.129-138
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• 2022

Reintroduction programs have been promoted across the world to recover and rehabilitate endangered birds through ex situ captive breeding and releasing to the nature. The ultimate aims of these reintroduction programs are recovery of sustainable populations in natural habitats. To ensure the success of the reintroduction programs, it is necessary to examine the followings in order to increase the success rate of releasing along with the development of captive breeding techniques: 1) Adequate habitat provision, 2) adaptability of captive-bred individuals, 3) survivability of released individuals, and 4) social interest and will. Before releasing captive-bred individuals, it should be reviewed whether there are habitats in which the limiting factor is removed, and assessed their long-term safety. The quantity and quality of the released individuals must be considered to increase the chances for mate selection, maintain genetic diversity, and acquire the ability to adapt to the wild. The release method must be decided in consideration of characteristics of the target habitats and individuals, and rational means such as careful observation, evaluation, and feedback must be provided throughout the release process. For the long-term success of recovery projects, social awareness, sustainable support, and related experts are needed. Satisfying these criteria can help to increase the success rates of reintroduction programs. For the bird reintroduction program in the future, the feasibility of the methods and procedures must be closely reviewed before starting.

• 한국환경생태학회지
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• 제27권6호
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• pp.666-675
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• 2013

이 연구는 2009년 3월에서 2012년 7월까지 한라산에 설치한 인공둥지에서 번식하는 박새류(Titmouse)의 고도변화에 따른 번식생태학적 특징을 밝히기 위하여 이루어졌다. 박새류의 최초산란일은 고도가 높아짐에 따라 늦어지는 양상을 보였고, 고도상승에 따른 기온감소가 최초산란일에 영향을 미치는 것으로 나타났다(p<0.05). 결과를 종합해보면, 번식기(4~6월)의 평균기온과 산란일 간에는 유의한 상관을 보이지는 않았다(p>0.05). 인공둥지 이용률은 지역과 연도별 차이는 없었으나 박새(Parus major)와 곤줄박이(Parus varius) 두 종간에는 차이가 있는 것으로 나타났다. 한배산란수는 종간에 차이가 있었으나(p<0.05) 고도와 연도별 차이는 없었다(p>0.05). 부화성공률, 이소성공률, 번식성공률은 각각 2011년 67.3%, 99.5%, 67.0%이었고, 2012년에는 71.3%, 96.8%, 69.0%로 이소성공률은 높았고, 부화성공률과 번식성공률은 비슷하게 나타났다. 고도 차이에 따른 기온의 변화가 번식시기에 영향을 미치는 것은 확인되었으나 다른 번식생태학적 특성과의 상관관계는 확인할 수 없었다. 따라서 고도에 따른 기온변화가 박새류의 번식에 미치는 영향을 보다 명확하게 밝히기 위해서는 미기후요인과 먹이원 등의 조사를 통한 장기적인 연구가 필요할 것이라 판단된다.

• Ecology and Resilient Infrastructure
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• 제7권4호
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• pp.388-395
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• 2020

외래생물은 경제 목적으로 수입되었으나, 최근에는 애완용으로 수입되는 사례가 증가하고 있다. 애완동물로 선호도가 높아진 리버쿠터와 중국줄무늬목거북은 2014년부터 사육개체수가 서서히 증가하다가 2017년에 180개체, 2019년에는 281개체를 기록하여 최대로 증가하였다. 그러나 수명이 긴 거북의 특성과 사육여건의 변화로 자연으로 버려진 개체가 발견되었다. 방출된 개체의 생태계위해성 평가를 통해 생물다양성법에 의해 생태계교란 생물로 지정되었다. 따라서 해당 거북 사육자가 계속 사육을 원할 경우 '생태계교란 생물 사육유예 허가 신청서'를 제출하여야 한다. 본 연구는 2020년 3월부터 9월까지 6개월간 접수된 신청서의 정보 (사육 시설의 적합성, 거북 개체수, 사육기간, 획득 방법, 사육자 지역 분포 현황 등)를 분석하고, 사육상태를 검토 결과를 제시하였다. 신청서는 총 614건이 접수되었으며, 사육자의 58%만이 적합한 사육상태를 조성한 것으로 평가되었기 때문에 사육자를 대상으로 동물복지 실현을 위해 적절한 사육 정보 제공과 생태계교란 예방을 위한 유기방지 교육이 필요한 것으로 사료된다. 또한, 신청서 내의 누락된 항목이 다수 발견된 점과 단발적인 신청에 따른 허가 방식으로 인한 문제 발생에 대비하여 대응방안을 만들고 지속적인 모니터링이 필요할 것으로 판단된다.