• Title/Summary/Keyword: Feeding ecology

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Interactions between Insect Species Feeding on Rumex obtusifolius: the Effect of Philaenus spumarius Feeding on the Ecology of Gastrophysa viridula

  • Kwon, Oh-Seok;Nam, Sang-Ho
    • The Korean Journal of Ecology
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    • v.23 no.2
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    • pp.175-180
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    • 2000
  • In order to study the insect-insect interaction of the insect community associated with Rumex obtusifolius. this experiment was designed in such a way that the feeding of one insect could indirectly affect the subsequent insect species through the changes in host plant (plant mediated insect-insect interaction ). Philaenus spumarius and Gastrophysa viridula were selected for the experiment. To investigate the effect of P. spumarius feeding on the ecology of G. viridula, first, statistical analyses were carried out. As results. no significant difference between Control and Experimental was found in the development patterns (Repeated Measures ANOVA, F=0.744, p=0.667) and survivorships (F=0.373. p=0.990). As the results from this experiment show, there was no effect on the ecology of G. viridula due to the previous feeding by P. spumarius on R. obtusifolius leaves.

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Feeding Ecology of the Blackthroat Seaperch Doederleinia berycoides in the Southern Seas of Korea (한국 남해 연안에 분포하는 눈볼대(Doederleinia berycoides)의 섭이생태)

  • Choi, Jung Hwa;Choi, Seung Hee;Lee, Dong Woo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.47 no.6
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    • pp.895-900
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    • 2014
  • The feeding ecology of Doederleinia berycoides from the southern sea of Korea was examined. Specimens were caught monthly from January 2007 to June 2008. The size of the specimens ranged from 6.8 to 39.8cm in total length (TL). The primary prey items of D. berycoides included fishes and shrimps. In autumn, feeding mainly crustacea and fishes feeding mainly in winter. The individuals of smallest size class (less than 15 cm TL) fed mainly on crustacea. The proportion of crustacea decreased as body size increased, whereas the consumption of fishes increased. Fishes accounted for almost (86%) stomach contents of larger individuals (more than 35 cm TL).

Nutrition Knowledge of and Attitudes toward Breast-Feeding and Food Habits in Relation to the Expected Infant Feeding Method among Male and Female College Students (남녀 대학생의 예상 수유방법에 따른 모유영양에 관한 지식과 태도 및 식습관의 비교)

  • Hyun, Wha-Jin;Lee, Jo-Yun
    • Korean Journal of Human Ecology
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    • v.5 no.2
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    • pp.161-171
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    • 1996
  • In order to provide the basic data on an education program for successful breast-feeding, the nutrition knowledge of and attitudes toward breast-feeding and the factors associated with infant feeding decision among male and female college students were investigated. The majority of students had correct knowledge of the maternal-infant bonding through breast-feeding and knew more about baby-centered benefits than about mother-centered benefits of breast-feeding. Students' attitudes toward breast-feeding were not so positive as expected, and male students had more positive attitudes toward breast-feeding than female students had. 54.8% of students answered to practice breast-feeding longer than 3 months. Nutrition knowledge scores and attitude scores were significantly higher in the breast-feeding decision group than in the formula-feeding decision group. The students residing in a rural community decided breast-feeding significantly more than the students residing in an urban community. It was concluded that nutrition knowledge about the breast-feeding played a significant role in deciding infant feeding method. In order to increase breast-feeding decision rates among college students, the education program may need to focus on understanding of correct nutrition knowledge about the benefits of breast-feeding. Also it would be important to have male students participated in education program.

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Feeding ecology of three tonguefishes, genus Cynoglossus (Cynoglossidae) in the Seto Inland Sea, Japan

  • Baeck, Gun-Wook;Park, Joo-Myun;Hashimoto, Hiroaki
    • Animal cells and systems
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    • v.15 no.4
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    • pp.325-336
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    • 2011
  • Feeding ecology was compared among the three tonguefishes Cynoglossus abbreviatus, C. joyneri and C. robustus, collected from Seto Inland Sea, Japan, from June 2000 to May 2001. They are benthivores, consuming mainly gammarid amphipods, shrimps, crabs, gastropods, bivalves and ophiuroids. C. abbreviatus consumed greater proportions of ophiuroids whereas C. joyneri and C. robustus ate more amphipods and shrimps. While C. abbreviatus consumed mostly ophiuroids in all size classes, the diets of C. joyneri and C. robustus showed ontogenetic changes in feeding habits; smaller individuals of C. joyneri and C. robustus consumed gammarid amphipods, whereas larger C. joyneri ate shrimps and gastropods, and larger C. robustus fed mainly on gastropods, crabs, bivalves and polychaetes. Cluster analysis based on diet similarities emphasized that the three Cynoglossus species could be categorized on a size-related basis into three feeding groups: smaller C. joyneri and C. rubustus (<25 cm TL) could be classified as group A, and the larger of them (>25 cm TL) as group B, whereas C. abbreviatus was categorized as group C. This means that some degree of resource partitioning can occur among the three Cynoglossus species. The seasonal changes in the diets were also significant for the three Cynoglossus species.

Research on the Size, Formation and Tendency to Evade the Road of the Feeding Flocks of Crane Species - Centering on the Effect of Road vs. Traffic Condition - (두루미류의 취식무리 크기 및 구성과 도로에 대한 회피 - 도로의 영향 vs 통행에 의한 영향? -)

  • Yoo, Seung-Hwa;Lee, Ki-Sup;Kim, In-Kyu;Kang, Tae-Han;Lee, Han-Soo
    • Korean Journal of Environment and Ecology
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    • v.23 no.1
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    • pp.41-49
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    • 2009
  • This research conducted a survey on the feeding crane's size, formation and distribution distance subsequent to road pattern and feeding flock's size during the wintering season eight times at the Cheolwon basin in Korea from December 2005 until February 2006. The survey results are as follows: First, the feeding flocks of the Red-crowned and White-naped Crane were found to mainly consist of two to four individuals. Mono-specific feeding flocks were more identified than hetero-specific feeding flocks in both Red-crowned and White-naped Cranes. There existed a significant difference in the ratio by size between the feeding Red-crowned and White-naped Cranes. The crane's average distribution distance from the paved road was much farther than from the unpaved road, paved farm road and unpaved farm road. In case of the white-naped crane, there was a difference in its distance length from between the road and farm road and there existed a significant difference only in the paved road in the distance length by road pattern between these two bird species[Red-crowned and White-naped Crane]. Such a result indicates that crane species don't prefer the road with frequent vehicular traffic to the road with low vehicular traffic. 5 or more individuals of feeding flocks of the Red-crowned Crane were located at a farther distance length from the paved road comparing to less than 5 individuals of the whole feeding flocks and less than 5 individual feeding flocks. 5 or more individuals of feeding flocks of the White-naped Crane were located at a farther distance length from the paved road, paved farm road and unpaved farm road than less than 5 individuals of feeding flocks of the White-naped Crane; however, there existed no difference in distance length subsequent to their group size. Conclusively, it was found out that the flocks with a larger size were more greatly affected by interrupting factors. Considering such results, there seems to be a more relation to the fact that larger size feeding flocks of crane species have a higher efficiency in the lookout for their surroundings.

Comparisons of Feeding Ecology of Euphausia pacifica from Korean Waters Using Lipid Composition (한국 근해의 난바다곤쟁이 Euphausia pacifica의 지방 조성에 의한 섭식 생태 비교)

  • Kim, Hye-Seon;Ju, Se-Jong;Ko, Ah-Ra
    • Ocean and Polar Research
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    • v.32 no.2
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    • pp.165-175
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    • 2010
  • Dietary lipid biomarkers (fatty acids, fatty alcohols, and sterols) in adult specimens were analyzed to compare and understand the feeding ecology of the euphausiid, Euphausia pacifica, from three geographically and environmentally diverse Korean waters (Yellow Sea, East China Sea, and East Sea). Total lipid content of E. pacifica from Korean waters was about 10% dry weight (DW) with a dominance of phospholipids (>46.9% of total lipid content), which are known as membrane components. A saturated fatty acid, C16:0, a monounsaturated fatty acid, C18:1(n-9), and two polyunsaturated fatty acids, C20:5(n-3) and 22:6(n-3), were most abundant (>60% of total fatty acids) in the fatty acid composition. Some of the fatty acids showed slight differences among regions although no significant compositional changes of fatty acids were detected between these regions. Phytol, originating from the side chain of chlorophyll and indicative of active feeding on phytoplankton, was detected all samples. Trace amounts of various fatty alcohols were also detected in E. pacifica. Specifically, krill from the Yellow Sea showed relatively high amounts of longchain monounsaturated fatty alcohols (i.e. 20:1 and 22:1), generally found in herbivorous copepods. Three different kinds of sterols were detected in E. pacifica. The most dominant of these sterols was cholest-5-en-$3{\beta}$-ol (cholesterol). The lipid compositions and ratios of fatty acid trophic markers are indicative of herbivory in E. pacifica from the Yellow Sea and East Sea (mainly feeding on dinoflagellates and diatoms, respectively). The lipid compositions and ratios of fatty acid trophic markers are indicative of carnivory or omnivory in E. pacifica from the East China Sea, mainly feeding on microzooplankton such as protozoa. In conclusion, lipid biomarkers provide useful information about krill feeding type. However, further analyses and experiments (i.e. gut content analysis, in situ grazing experiment, etc.) are needed to better understand the feeding ecology of E. pacifica in various marine environments.

Feeding Ecology of the White-spotted Conger Eel(Conger myriaster) in the Southern Sea of Korea (한국 남해 연안에 분포하는 붕장어(Conger myriaster)의 섭이생태)

  • Choi, Jung-Hwa;Choi, Sung-Hee;Kim, Jong-Bin;Park, Jeong-Ho;Oh, Chul-Woong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.4
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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.

Feeding Ecology of Black Rockfish, Sebastes inermis (볼락, Sebastes inermis 의 섭식상태)

  • KIM Chong-Kwan;KANG Yong-Joo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.5
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    • pp.637-641
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    • 1999
  • This study was carried out to understand feeding ecology of black rockfish, Sebastes inermis in the coastal waters off Shinsudo, Sachon. The specimens were collected by angling, gill net, small danish seine, and long-bag net from February 1984 to May 1985. The fish consisted of 5 age groups from 0 to 4. Feeding activity was more intensive in the early morning and late afternoon in spring and summer, but the fish showed intermittent feeding activities in autumn and winter. Although the food items of the fish changed slightly by seasons and with growth of the fish, main food items were cope pods, gammarids, caprellids, carideans, polychaetes, and brachyurans. Of these food items, cope pods were major preys for the fish of age group 0, and gammarids over age group 1. Evenness and diversity of the food items increased as the fish grew. In consideration of feeding organs, digestive organs and stomach contents of the fish, S. inermis seemed to be not only carnivore but also visual feeder consuming mainly small crustaceans.

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