• Title/Summary/Keyword: Fish school

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Fish Composition and Trophic Guild Analysis as a Collection of Basic Data for Ecosystem Health Assessments in Yeongsan Lake

  • Choi, Ji-Woong;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.40 no.4
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    • pp.546-552
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    • 2007
  • The objectives of this study were to analyze fish compositions, based on trophic guilds and tolerance guilds and determine community characteristics structure at five sampling sites of Yeongsan Lake during July 2006-May 2007. Total number of species sampled was 30 species and the number was 1350. Cyprinidae (77%) and Centrarchidae (15.7%) dominated the community and then followed by Cobitidae(2.7%), Gobiidae(2.4%), Mugilidae (0.5%), and others (0.1%). The relative abundance of tolerant and omnivore species at all sites was 63% and 77% of the total, respectively, suggesting an ecological degradations in the Lake. Exotics species such as large mouth bass (Micropterus salmoides), which is a top-carnivore in the water distributed at all sampling sites, implying that ecological disturbance was severe based on previous reference of US EPA (1991). Also, we found external anomalies such as external deformities, bleeding and tumors and not found migratory fish. Analysis of fish community structure showed that species diversity index and richness index was the highest in Site 1 and the dominance index was the highest in Site 2. In this study, high proportions of tolerant species and omnivore species, widespread exotic species, and frequent observations of abnormal fish. Such problems may be directly or indirectly associated with high nutrient enrichments and the reduced flow velocity by the dam construction. The ecosystem restoration by dam removal or removal of exotic top-carnivore fish may be one of the best strategies for better lak management.

Use of Geographical Parameters of Fish School in the Estimation of Fish School Abundance Using Scanning Sonar (스캐닝 소너에 의한 어군량 추정에 있어서 어군의 기하학적 파라메터의 이용)

  • Lee, Yoo-Won;Mukai, Tohru;Iida, Kohji;Shin, Hyeong-Il
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.38 no.3
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    • pp.197-201
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    • 2002
  • The object of this study was to find out the probability of the abundance estimation by geographical parameters of fish school during the acoustic survey using scanning sonar. The acoustic survey was carried out in Funka Bay, off southern Hokkaido, Japan in December 1998. The 180-degree scanning sonar and the echo sounder were used simultaneously. The relationship was examined between geographical parameters (fish school area and volume) measured by sonar and area back scattering coefficient by the echo sounder. The obtained result showed positive correlation. Therefore, the use of geographical parameters of fish school is a useful method in estimating fish school abundance in the acoustic survey using sonar.

DNA barcoding for fish species identification and diversity assessment in the Mae Tam reservoir, Thailand

  • Dutrudi Panprommin;Kanyanat Soontornprasit;Siriluck Tuncharoen;Santiwat Pithakpol;Korntip Kannika;Konlawad Wongta
    • Fisheries and Aquatic Sciences
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    • v.26 no.9
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    • pp.548-557
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    • 2023
  • The purposes of this research were to identify fish species using DNA barcodes or partial sequences of cytochrome b (Cytb) and to assess the diversity of fish in the Mae Tam reservoir, Phayao province, Thailand. Fish samples were collected 3 times, during the winter, summer, and rainy seasons, from 2 sampling sites using gillnets with 3 mesh sizes (30, 50, and 70 mm). A total of 34 representative samples were classified into 12 species, 7 families and 6 orders by morphological- and DNA barcoding-based identifications. However, one cichlid species, Cichlasoma trimaculatum, could only be identified using DNA barcoding. Family Cyprinidae had the greatest diversity, 50.00%. The diversity, richness and evenness indices ranged from 0.43-0.65, 0.64-1.46, and 0.27-0.40, respectively, indicating that fish diversity at both sampling sites was relatively low. A comparison of the catch per unit effort (CPUE) with 3 different mesh sizes found that the 50 mm mesh size was the best (474.80 ± 171.56 g/100 m2/night), followed by the 70 mm (417.41 ± 176.24 g/100 m2/night) and 30 mm mesh sizes (327.88 ± 115.60 g/100 m2/night). These results indicate that DNA barcoding is a powerful tool for species identification. Our data can be used for planning the sustainable management of fisheries resources in the Mae Tam reservoir.

Semiautomatic 3D Virtual Fish Modeling based on 2D Texture

  • Nakajima, Masayuki;Hagiwara, Hisaya;Kong, Wai-Ming;Takahashi, Hiroki
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1996.06b
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    • pp.18-21
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    • 1996
  • In the field of Virtual Reality, many studies have been reported. Especially, there are many studies on generating virtual creatures on computer systems. In this paper we propose an algorithm to automatically generate 3D fish models from 2D images which are printed in illustrated books, pictures or handwritings. At first, 2D fish images are captured by means of image scanner. Next, the fish image is separated from background and segmented to several parts such as body, anal fin, dorsal fin, ectoral fin and ventral fin using the proposed method“Active Balloon model”. After that, users choose front view model and top view model among six samples, respectively. 3D model is automatically generated from separated body, fins and the above two view models. The number of patches is decreased without any influence on the accuracy of the generated 3D model to reduce the time cost when texture mapping is applied. Finally, we can get any kinds of 3D fish models.

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Survey of Zoonotic Trematode Metacercariae in Fish from Water systems of Geum-gang (River) in Republic of Korea

  • Sohn, Woon-Mok;Na, Byoung-Kuk;Cho, Shin-Hyeong;Kim, Cheon-Hyeon;Hwang, Min-Ah;No, Kyeong-Woo;Kim, Jai-Dong
    • Parasites, Hosts and Diseases
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    • v.59 no.1
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    • pp.23-33
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    • 2021
  • The infection status of zoonotic trematode metacercariae (ZTM) was surveyed in freshwater fishes from the water systems of Geum-gang (River) in the Republic of Korea (Korea). A total of 1,161 freshwater fishes from 6 local sites of Geum-gang were examined with the artificial digestion method for 4 years (2012-2015). Clonorchis sinensis metacercariae were detected in 122 (37.2%) out of 328 fishes in the positive fish species from 4 surveyed areas, and their mean intensity was 43 per fish infected. Metagonimus spp. metacercariae were found in 432 (51.7%) out of 835 fishes in the positive fish species from all 6 surveyed areas, and their mean intensity was 30 per fish infected. Centrocestus armatus metacercariae were detected in 285 (75.0%) out of 380 fishes in the positive fish species from 6 surveyed areas, and their mean intensity was 2,100 per fish infected. Echinostoma spp. metacercariae were found in 56 (19.7%) out of 284 fishes in the positive fish species from 5 surveyed areas, and their mean intensity was 10 per fish infected. Clinostomum complanatum metacercariae were detected in 98 (57.3%) out of 171 fishes in the positive fish species from only 2 surveyed areas, and their mean intensity was 11 per fish infected. Conclusively, the endemicity of ZTM is not so high in fishes from water systems of Geum-gang in Korea although it is more or less different by fish species, surveyed areas and ZTM species.

Karyotype Analysis and Physical Mapping of rDNAs Using McFISH in Jeffersonia dubia Benth (깽깽이풀의 핵형분석과 McFISH를 이용한 rDNA의 물리지도 작성)

  • Kim, Soo-Young;Choi, Hae-Woon;Koo, Dal-Hoe;Kim, Chan-Soo;Bang, Jae-Wook
    • Korean Journal of Medicinal Crop Science
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    • v.13 no.1
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    • pp.48-51
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    • 2005
  • Karyotype analysis and chromosomal locailization of 45S and 5S rDNAs using McFISH (multi-color fluorescence in situ hybridization) were carried out in Jeffersonia dubia Benth., which is one of medicinal plants belonging to Berberidaceae. The somatic metaphase chromosome number was 2n=2x=12 and the size of chromosomes ranged $1.95{\sim}3.50\;{\mu}m$. The chromosome complement consisted of two pairs of metacentrics (chromosomes 1 and 3), two pairs of submetacentrics (chromosomes 2 and 4) and two pairs of subtelocentrics (chromosomes 5 and 6). In McFISH, one pair of 45S rDNA site was detected on the centromeric region of chromosome 2 and three pairs of 5S rDNA sites were detected on the short arm of chromosomes 4, 5 and 6, respectively.

Studies on the Behaviour of Fish Schools in the Main-Net of a Large Scale Set-Net Using a Scanning Sonar ( III ) - The Behaviour of Anchovy Engraulis Japonica Sonar-III (소나 관찰에 의한 대형정치망내 어군행동의 연구 ( III ) - 원통내 멸치어군의 행동과 원통의 기능)

  • Kim, Mung-Kwan;Inoue, Yoshihiro;Park, Jeong-Sik
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.32 no.3
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    • pp.217-222
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    • 1996
  • The moving behaviour of anchovy schools(There were small schools of sardine and round-herring in this anchovy schools} in the bag - net of a large scale set - net was investigated using a scanning sonar, in the Kishihata set - net fishing ground located in Nanao city Ishigawa prefecture, Japan from Dec. 1st to Dec. 4th, 1992. The results obtained are summarized as follows ; 1. Moving behaviour of fish schools between two bag - nets was more in the daytime than in the nighttime. 2. The rate of entering fish schools from the first bag -- net to the second bag - net were 78% when the fish school in the second bag -- net existed. The result suggest that fish school existence in the second bag - net affected the rate of entering fish schools from the first bag - net to the second- bag - net. However, the time of stay of fish school that entered the second bag -- net was very short when the fish school in the second bag - net existed densely. The result suggest that a high fish density in the second bag - net might enlarge the escape rate 3. The majority of fish schools moved to the center and off shore side of the bag - net when fish schools entered the bag - net.

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Zoonotic Trematode Metacercariae in Fish from Phnom Penh and Pursat, Cambodia

  • Chai, Jong-Yil;Sohn, Woon-Mok;Na, Byoung-Kuk;Yong, Tai-Soon;Eom, Keeseon S.;Yoon, Cheong-Ha;Hoang, Eui-Hyug;Jeoung, Hoo-Gn;Socheat, Duong
    • Parasites, Hosts and Diseases
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    • v.52 no.1
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    • pp.35-40
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    • 2014
  • A survey was performed to investigate the infection status of freshwater fish with zoonotic trematode metacercariae in Phnom Penh and Pursat Province, Cambodia. All collected fish with ice were transferred to our laboratory and examined using the artificial digestion method. In fish from Phnom Penh, 2 kinds of metacercariae (Opisthorchis viverrini and Haplorchis yokogawai) were detected. O. viverrini metacercariae were positive in 37 (50.0%) of 74 fish in 11 species (average no. metacercariae/fish, 18.6). H. yokogawai metacercariae were detected in 23 (57.5%) of 40 fish in 5 species (average no. metacercariae/fish, 21.0). In fish from Pursat Province, 5 kinds of metacercariae (O. viverrini, H. yokogawai, Haplorchis pumilio, Centrocestus formosanus, and Procerovum sp.) were detected; O. viverrini metacercariae (n=3) in 2 fish species (Henicorhynchus lineatus and Puntioplites falcifer), H. yokogawai metacercariae (n=51) in 1 species (P. falcifer), H. pumilio metacercariae (n=476) in 2 species (H. lineatus and Pristolepis fasciata), C. formosanus metacercariae (n=1) in 1 species (H. lineatus), and Procerovum sp. metacercariae (n=63) in 1 species (Anabas testudineus). From the above results, it has been confirmed that various freshwater fish play the role of a second intermediate host for zoonotic trematodes (O. viverrini, H. yokogawai, H. pumilio, C. formosanus, and Procerovum sp.) in Cambodia.

Tracheal and esophageal injury by fish bone

  • Kim, Jae-Bum;Park, Chang-Kwon
    • Korean Journal of Bronchoesophagology
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    • v.14 no.1
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    • pp.42-45
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    • 2008
  • Tracheal injury associated with esophageal injury due to fish bone is very rare. Also, treatment of mediastinitis due to esophageal perforation when it is diagnosed late remains controversial. We report the case that we have successfully experienced treatment of mediastinitis due to tracheal and esophageal injury by fish bone.

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A Convergence Study on Desired Frequency of Meat Side Dishes and Preference of Fish Side Dishes in School Meals of High School Girls in Coastal Cities (해안도시 여고생의 학교 급식 육찬의 희망횟수 및 어찬 기호도에 관한 융합연구)

  • Park, Pil-Sook;Jeon, Jin-Kyung;Kim, Gum-Ran;Park, Mi-Yeon
    • Journal of the Korea Convergence Society
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    • v.11 no.1
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    • pp.65-75
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    • 2020
  • This study is a convergence study of 596 high school girls in order to confirm the relationship between the desired number of meat side dishes and preference of fish side dishes in school meals. Data were analyzed by χ2-test, ANOVA-test, and Duncan's test using SPSS 22.0 program. The results of the study were as follows. The scores of the subjects for promoting palatability were highest in the items 'Easy to eat' and 'Without fishy'. The scores of 'Nutrition Education', 'Combined with Preferred Food', 'Without Fishy' and 'Add Preferred Flavor' tended to increase significantly as the desired frequency of meat side dishes increased from 'less than three times a month' to 'more than five times a week'. The findings of the study confirmed the relationship between the desired frequency of meat side dishes and preference of fish side dishes. Therefore, this study is expected to provide high school girls with a way to increase fish preference.