• Title/Summary/Keyword: feeding habits

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Diet composition and feeding habits of Oreochromis niloticus (Linnaeus, 1758) in Lake Shala, Ethiopia

  • Wagaw, Solomon;Mengistou, Seyoum;Getahun, Abebe
    • Fisheries and Aquatic Sciences
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    • v.25 no.1
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    • pp.20-30
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    • 2022
  • The present study was carried out to investigate the food and feeding habits of Oreochromis niloticus in Lake Shala to manage this species in this high Soda Lake. Stomachs of 226 fish (65.9%) had different food items, while those of 117 fish (34.1%) were empty. Phytoplankton was the dominant food categories occurring in 90.3% of the stomachs estimated and contributed 75.5% of the total volume. Bacillariophyceae (Nitzschia, Anomoeoneis, Navicula and Melosira) were identified as the most desired phytoplankton item. The prey items of O. niloticus differed among size classes (ANOVA, p < 0.05). The main prey items were zooplankton by the smaller-size class, and phytoplankton in fish of the larger-size class. Seasonal variation in the diet composition was evident (t-test, p < 0.05) and zooplankton, chironomids, nematodes, fish scales and detritus were important during the wet season, while phytoplankton predominates during the dry season. This study concludes that O. niloticus had a phytoplanktivores feeding mainly on phytoplankton and their feeding habits influenced by season and fish size in Lake Shala.

Feeding Habits of Sebastes thompsoni in the Coastal Waters off Busan, Korea (부산 주변 해역에서 채집된 불볼락(Sebastes thompsoni)의 식성)

  • Huh, Sung-Hoi;Nam, Ki-Mun;Choo, Hyun-Gi;Baeck, Gun-Wook
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.1
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    • pp.32-38
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    • 2008
  • We studied the feeding habits of Sebastes thompsoni based on 421 specimens obtained in monthly collections between January and December 2005 in the coastal waters off Busan, Korea. S. thompsoni was a crustacean feeder, and consumed mainly shrimp and euphausiids. Its diet also included small quantities of amphipods, cephalopods, and fish. It showed distinct ontogenetic changes in feeding habits. Smaller individuals (14-17 cm standard length (SL)), mainly consumed euphausiids. The portion of these prey items decreased with increasing fish size, and larger individuals (>20 cm SL) consumed mainly shrimp such as Leptochela sydniensis.

Feeding habits of Acentrogobius pellidebilis in an eelgrass(Zostera marina) bed (해초지에서 서식하는 점줄망둑(Acentrogobius pellidebilis)의 먹이습성)

  • Kwak, Seok-Nam;Huh, Sung-Hoi;Kim, Ha-Won
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.46 no.4
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    • pp.358-367
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    • 2010
  • Feeding habits of Acentrogobius pellidebilis collected from in an eelgrass(Zostera marina) bed from January to December 2006 were studied. A. pellidebilis ranged form 1.6 to 6.9 cm in standard length were determined. A. pellidebilis was a carnivore which consumed mainly copepods, polychaetes, and amphipods. Its diets included small quantities of isopods, seaweeds, nematods, and gastropods. It showed ontogenetic changes in feeding habits. Smaller individuals (<2.0cm SL) fed mainly on copepods. While the consumption of copepods decreased with increasing fish size, the consumption of polychaetes and amphipods were increased. Dietary breadth index was varied with fish size.

Feeding Habits of Rudarius ercodes in a Zostera marina Bed

  • Kwak Seok Nam;Huh Sung-Hoi
    • Fisheries and Aquatic Sciences
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    • v.7 no.1
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    • pp.46-50
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    • 2004
  • Feeding habits of Rudarius ercodes collected from a Zostera marina bed in Jindong Bay, Korea were studied. R. ercodes was a omnivore which consumed mainly gammarid amphipods, polychaetes and eelgrass (z. marina). Its diets also included a small amount of copepods, urochordates and caprellid amphipods. R. ercodes showed ontogenetic changes in feeding habits. Small individuals less than 2cm SL fed mainly on copepods, however, gammarid amphipods and polychaetes were heavily selected with increasing fish size. The consumption of eelgrass by R. ercodes was $10-20\%$ all size classes. The dietary breadth of R. ercodes were varied with fish size

Feeding Habits of Pseudoblennius cottoides (가시망둑 (Pseudoblennius cottoides)의 식성)

  • HUH Sung-Hoi;KWAK Seok Nam
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.1
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    • pp.37-44
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    • 1998
  • Feeding habits of Pseudoblennius cottoides collected from the eelgrass bed in Kwangyang Bay from January 1994 to December 1994 were studied. Pseudoblennius cottoides was a carnivore which mainly consumed fishes, caridean shrimps, and amphipods. Its diets included small Quantities of tanaids, copepods, isopods, mysids, and polychaetes. It showed ontogenetic changes in feeding habits. Fishes were heavily selected as the body size of P. cottoides increases. Fishes and caridean shrimps were major prey organisms for all seasons.

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Feeding Habits of the Redbanded Searobin Lepidotrigla guentheri in the Coastal Waters off Gori, Korea (고리 주변해역에서 출현하는 꼬마달재 (Lepidotrigla guentheri)의 식성)

  • Baeck, Gun-Wook;Huh, Sung-Hoi;Choi, Hee-Chan;Park, Joo-Myun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.4
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    • pp.372-377
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    • 2011
  • The feeding habits of the redbanded searobin Lepidotrigla guentheri were studied using 186 specimens collected from September to November, 2006, in the coastal waters off Gori, Korea. The sizes of L. guentheri ranged from 7.1 to 16.7 cm total length(TL). L. guentheri is a bottom-feeding carnivore that consumes mainly shrimp, especially Leptochela sydniensis, amphipods, and crabs. Its diet also includes small quantities of stomatopods, mysids, cumaceans, euphausiids, polychaetes, and copepods. Our feeding-strategy graphical method reveled that L. guentheri is a specialized feeder, with a narrow niche width. L. guentheri mainly consumed shrimp of all size classes and did not show significant ontogenetic changes in feeding habits. Smaller individuals(7-11 cm TL) secondly consumed amphipods, with the portion of amphipods in the total diet decreasing as body size increased. Prey size increased significantly as the fish grew in size.

Feeding Habits of Hexagrammos otakii off the Yoesu Coast of Korea (여수 연안에서 서식하는 쥐노래미(Hexagrammos otakii)의 식성)

  • Jung, Jin Ho;Kim, Heeyong;Moon, Seong Yong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.5
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    • pp.705-713
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    • 2022
  • The feeding habits of Hexagrammos otakii were studied by analyzing the stomach contents of 508 specimens collected from July 2009 to December 2010 off the Yeosu coast of Korea. The total length of the H. otakii specimens ranged from 10.7 to 41.5 cm. H. otakii was found to be a bottom-feeding carnivore that mainly consumed brachyura, amphipoda, but also sonsumed cephalopoda, pisces, anomura, polychaeta, and gastropoda. It was shown through relative importance analysis that the benthic share was 58.1% for brachyura, 24.5% for amphipoda, 7.5% for caridea, and 7.3% for pisces. Brachyura was the main prey item for H. otakii, occupying 35% of the stomach contents. The proportion of brachyura and amphipoda decreased with the growth of H. otakii, and their decrease paralleled the increased consumption of pisces. The shift in feeding habits to larger prey organisms with increasing fish size seems to be one of survival strategies to maximize net energy gain.

Feeding Habits of Daggertooth Pike Conger Muraenesox cinereus in the Coastal Water off Goseong, Korea (경남 고성 주변해역에서 출현하는 갯장어(Muraenesox cinereus)의 식성)

  • An, Young-Su;Park, Joo-Myun;Kim, Hyeon-Ji;Baeck, Gun-Wook
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.45 no.1
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    • pp.76-81
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    • 2012
  • The feeding habits of daggertooth pike conger Muraenesox cinereus were studied using 380 specimens collected in the coastal waters off Goseong, Korea, from June to September, 2011. The M. cinereus ranged from 10.0-23.7 cm in anal length (AL). M. cinereus is a piscivore that consumes mainly fish. Engraulis japonicus was the preferred prey, but its diet also included small numbers of crabs, shrimps, cephalopods, and bivalves. The feeding strategy graphical method revealed that M. cinereus is a specialized feeder with a narrow niche width. All size classes of M. cinereus consumed fish and M. cinereus did not show significant ontogenetic changes in feeding habits. The diet overlap index between size classes was >0.96, indicating high diet similarities. The prey size increased significantly with M. cinereus size.

Feeding Habits of Juvenile Liparis tanakai in the Eelgrass, Zostera marina Bed in Kwangyang Bay (광양만 잘피밭에 서식하는 꼼치 (Liparis tanakai) 유어의 식성)

  • KWAK Seok Nam;HUH Sung-Hoi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.4
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    • pp.372-377
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    • 2003
  • Feeding habits of juvenile Liparis tanakai collected from the eelgrass bed in Kwangyang Bay were studied. L. tanakai (2.0-6.0 cm SL) was a carnivore which consumed mainly amphipods (caprellids and gammarids) and caridean shrimps. Its diets also included a large amount of copepods, polychaetes and small fishes. Three distinct ontogenetic feeding groups were noted: (1) the individuals of 2.0-2.5 cm SL preyed heavily on copepods, (2) individuals of 2.5-4.0 cm SL fed mainly on amphipods. (3) individuals over 4.0 cm SL preyed mainly on caridean shrimps and small fishes. The dietary breadth of each size class showed relatively low value, and this means that juvenile L. tanakai depends on only few kinds of food organisms.

Feeding Habit of Limanda yokohamae in the Eelgrass (Zostera marina) Bed in Kwangyang Bay (광양만 잘피밭에 서식하는 문치가자미 (Limanda yokohamae)의 식성)

  • KWAK Seok Nam;HUH Sung-Hoi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.5
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    • pp.522-527
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    • 2003
  • Feeding habits of Limanda yokohamae collected from the eelgrass bed in Kwangyang Bay were studied. L. yokohamae (1-16 cm SL) was a carnivore which consumed mainly polychaetes. Its diets included a significant quantity of amphipods (gammarids and caprellids) as well as small quantities of gastropods and ophiuroids. L. yokohamae showed ontogenetic changes in feeding habits. Small individuals less than 4 cm SL preyed mainly on amphipods. However, polychaetes were heavily selected with increasing fish size while the portion of the diet attributable to amphipods decreased sharply. Polychaetes were the major prey organisms for all seasons. Dietary breadth of each size class shows relatively low value, and this means that L. yokohamae depends on only few kinds of food organisms.