• 한국수산과학회지
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• 제41권4호
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• pp.282-288
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• 2008

Feeding ecology of the white-spotted conger eel Conger myriaster in the Southern Sea of Korea was examined. Specimens were caught monthly from January 2004 to December 2006. Primary prey items of C. myriaster included fish, shrimp, and crabs. C. myriaster exhibited a nocturnal feeding strategy and preyed upon a wide range of pelagic fish groups(e.g., Engraulis japonicus, Glossanodon semifasciatus, and Maurolicus muelleri). This species was also an opportunistic feeder that exploited the available prey in each area(i.e., fish in the A area and shrimp in the B area). The composition of the diet of C. myriaster exhibited seasonal fluctuations that were related to food availability during each season. The observed ontogenetic shifts in diet were relatively clear, despite substantial overlap between the 10 cm and 20 cm groups of C. myriaster.

• 환경생물
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• 제17권4호
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• pp.401-405
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• 1999

북방산개구리의 산란특성 및 발생과정을 연구하기 위하여 1998년 2월 중순에서 3월말까지 경기도, 경상북도, 강원도를 중심으로 남한의 전지역을 대상으로 표본을 채집하였다. 북방산개구리의 산란시기는 2월말에서 3월말사이에 주로 이루어지며, 산란장소는 정수지와 유수지를 모두 선택하나 유수지에 산란하는 경우 알의 형태는 뭉쳐진 불규칙한 공 모양으로 돌이나 수초와 같은 기질에 부착하며, 정수지의 경우 타원형의 계란모양을 이루고 기질에 부착하지 않는다. 발생과정은 산란 후 일주일이 지나면 대부분 부화하고 71일이 경과하면 전 발생과정을 완료한다. 발생과정이 비교적 짧은 것은 먹이원이 풍부한 계절에 적극적인 포식활동을 위한 것으로 판단된다.

• 환경생물
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• 제21권4호
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• pp.342-351
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• 2003

The southern rough shrimp Trachysalambria curvirostris (Stimpson) was monthly sampled from the coastal area of Yeosu, Korea from June 2000 to May 2001 and its stomach contents were investigated. Mysids and amphipods were the most dominant prey, comprising >40% of the diet in both % occurrence and % abundance. In particular, mysids were most important food without regard to seasons, size classes, or sexes. The abundance and occurrence composition of food items showed a seasonal fluctuation: mysids and amphipods were the predominant prey items in spring (33.8%), summer (41.1%), autumn (43.9%), and winter (49.2%). For small-sized shrimps (＞25 mm CL), mysids and amphipods consist of more than 45% of its food in both % abundance and % occurrence. For large-sized shrimps (>25 mm CL), these were clearly dominant. The quantities and items of food did not differ in both genders, which mainly fed on mysids and amphipods. The trophic diversity and equality of diet varied with seasons and size classes. The diet diversity for smaller shrimps was highest in spring, while that for the larger shrimp lowest in winter. Also, the mandibular structure of Trachysalambria curvirostris indicates that the species is carnivorous.

• 한국어류학회지
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• 제13권4호
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• pp.230-236
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• 2001

강원도 홍천군 서면 반곡리에서 2000년 1월부터 12월까지 Gobiobotia brevibarva를 대상으로 식성을 조사 연구하였다. G. brevibarba의 주요 먹이 생물은 Ephemeroptera, Trichoptera 그리고 Diptera였으며 그 밖에 Plecoptera와 Coleoptera 등이 검출되었다. 성장함에 따라 먹이 조성에 있어 변화를 보이는데 작은 체장 (21~50 mm)에서는 Diptera, Ephemeroptera를 주로 먹었으나 성장하면서 다양한 먹이와 비교적 크기가 큰 Trichoptera로 먹이 전환이 일어났다. Ephemeroptera는 봄 과 여름 그리고 가을에 양의 선택성을 겨울에는 음의 선택성을 나타낸 반면 Diptera는 3월과 10월 그리고 11월에 양의 선택성을 나타내었다.

• 환경생물
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• 제24권1호
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• pp.29-37
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• 2006

강원도 홍천군 서석면 생곡리에서 2002년 4월부터 2003년 3월까지 하천의 상류수역에 서식하는 한국 특산종인 R. kumgangensis의 식성에 대하여 조사하였다. R. kumgangensis는 주로 Ephemeroptera, Diptera, Terrestrial insects와 Trichoptera를 섭식하는 식충성 어류로 밝혀졌다. 주요한 먹이생물은 깔다구류(Chironomus sp.)였다. 크기가 작은 개체군에서는 Diptera와 같은 작은 크기의 먹이를 섭식하고, 성장함에 따라 Ephemeroptera와 Terrestrial insects같은 크기가 큰 먹이로의 먹이 전환이 일어난다. 또한 계절의 변화에 따라 먹이항목의 상대적 비율이 변화한다.

• Journal of Ecology and Environment
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• 제48권3호
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• pp.214-221
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• 2024

Background: To identify and avoid predators, amphibians rely on chemical cues. Onychodactylus koreanus undergo two to three years of the larval stage in mountainous streams, where they encounter various predators. We aimed to identify the potential predators of O. koreanus larvae based on their antipredator responses to predator odors. Additionally, we examined whether the response was innate or can be strengthened by predator olfactory learning. Results: In Experiment 1, O. koreanus larvae exhibited a substantial antipredator response to Chinese minnow (Rhynchocypris oxycephalus) odor but not to Korean freshwater crayfish (Cambaroides similis) odor. In Experiment 2, O. koreanus larvae, who did not previously expose to R. oxycephalus odor, demonstrated a substantial antipredator response to it. Experiment 3 indicated that predator olfactory learning of R. oxycephalus did not enhance the antipredator response of the larvae. Conclusions: Rhynchocypris oxycephalus could prey on O. koreanus larvae, whose antipredator response to R. oxycephalus odor is innate and not enhanced by olfactory learning. Further investigation into the olfactory system of this species may provide insights into the life cycle of O. koreanus, uncovering hidden underground breeding sites and unknown breeding periods.

• Fisheries and Aquatic Sciences
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• 제10권4호
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• pp.179-185
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• 2007

Understanding dietary habits is one of the most important factors in studying food webs and other ecological processes. Here we designed universal primers to amplify portions of the 18S and 28S rDNA sequences to examine gut contents using PCR techniques. The gut contents of sailfin sandfish (Arctoscopus japonicus) and pacific squid (Todarodes pacificus) were examined. In total, 11 families of prey were identified with 18S and 28S rDNA using the universal primers. The DNA sequence data indicated that the primer sets successfully amplified a wide spectrum of species and represented gut contents in a relatively convenient way. We found that information in the NCBI database was not yet sufficient to discriminate the species we isolated. In addition, technology for the separation of heterogeneous PCR products and better resolution and quantification protocols would help increase data accuracy.

• Applied Microscopy
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• 제46권2호
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• pp.89-92
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• 2016

The bluegill Lepomis macrochirus is an invasive species, not native to Korea, introduced for aquaculture. This species is ranked as a new top predator due to its massive aquatic carnivorous and herbivorous nature by acute vision and the absence of a natural enemy. The visual cells of the retina of L. macrochirus are composed of short single cones and equal double cones and long and bulky rods by light and electron microscopes. In particular, the cones show a regular square mosaic arrangement. This pattern is widely considered as a strong predator. With regard to the visual system, this mosaic pattern may closely be related to a dynamic visual acuity to track and hunt prey.

• 한국물환경학회지
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• 제28권2호
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• pp.185-196
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• 2012

The fish community within the lake and 5 tributaries of Lake Chungju in spring and autumn, 2009 was surveyed. In this study, the total 128,506 individuals were collected belonging to 11 families 29 genera 34 species. The most dominant species was Squalidus japonicus coreanus that account for 91.6% of population and 49% of biomass of fish community. In the point of population, dominant species were small-sized species, which became the prey of big-sized predatory species. In the point of biomass, dominant species were predatory species which were large-sized. The most dominant species in lacustrine area was S. japonicus coreanus which accounted for 92.2% of total population and 49.1% of total biomass. The most dominant species of tributary streams was Tridentiger brevispinis which accounted for 66.4% of total population and 55.1% of total biomass. The site of C3 in lacustrine area and Dongdal-cheon in tributary streams collected the most number of species. Through ecological health evaluation of five tributary streams using 8 metric index of biological integrity (IBI) model, two streams (Dongdal-cheon, Kwang-cheon were evaluated as, "B", "good" condition, and Jangsung-cheon obtained grade C indicating "Fair" condition, Jecheon-cheon obtained grade D indicating "Poor" condition based on IBI model. Lepomis macrochirus which was designated as a domestic ecosystem-disturbing alien species with wide food niche have shown tendency to increase the number of individuals since 1991 indicating the adverse effect on not only fish community but also aquatic ecosystem food web of Lake Chungju.

• 한국습지학회지
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• 제13권1호
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• pp.139-148
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• 2011

거미의 웹 건축 행동은 먹이 사냥을 위한 투자 행동이며, 적극적인 포식 전략의 반영이다. 성공적인 포식전략 수립을 위해서 개체는 먹이 동물로부터 오는 감각 정보를 반영해야 할 것이다. 본 연구는 우리나라에 널리 분포하는 대표적 논거미인 긴호랑거미(Argiope bruennichi)의 건축 행동이 피식자인 왕귀뚜라미(Teleogryllus emma)에 의해 제공되는 감각 정보를 바탕으로 수정되는가를 알아보기 위해 수행되었다. 웹의 물리적 구조가 수정되는 양상을 보기 위해 감각 자극 전과 후에 건축된 웹의 구조를 정량적으로 측정하고 대조군과 비교 분석하였다. 먹이가 공급되지 않는 상황에서 웹 건축 행동을 보인 개체의 수는 대조군(자극 없음)과 실험군(자극 공급)에서 모두 감소하는 경향을 보였다. 대조군과 실험군에서 나타난 증감 양상이 뚜렷한 차이를 드러내 않았다. 왕귀뚜라미에 의한 자극 공급 1일째에 해당하는 날에 실험군 웹 건축 행동은 전일 대비 3.7% 감소한대 반해 대조군은 11.8% 감소하는 차이를 나타냈다. 흰띠줄 건축 행동 역시 전반적으로 감소하는 경향이 나타났다. 대조군에서 흰띠줄을 건축한 개체수가 자극 1일에 14.7% 감소한데 비해, 실험군에서는 7.4%로 두 배 가량 감소 경향이 낮게 나타났다. 본 실험 디자인에 의한 연구 결과는 개체가 감각 정보에 따라 웹의 높이와 넓이를 수정하지 않는 것으로 나타났다.