• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.305-312
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• 2023

Diet composition and feeding strategy of the largehead hairtail, Trichiurus japonicas were studied using 375 specimens collected by purse seine, set net fisheries and lure fishing from February 2021 to January 2022 in the southern sea of Korea. The anal length (AL) of these specimens was from 3.4~49.0 cm. T. japonicus fed majorly on Fishes (especially Engraulis japonicus) based on ranking index (%RI=99.3). Fishes were the main prey items for all size classes. T. japonicas also showed size-related dietary shift from E. japonicus to T. japonicus, Larimichthys polyactis and Engraulidae. Fishes were the main prey items for all seasons. The main fish prey during spring and summer was E. japonicus, but in the autumn and winter, the E. japonicus portion decreased, and T. japonicus, L. polyactis, and Engraulidae portion increased. T. japonicus were specialized feeders with E. japonicus as their dominant prey.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.199-200
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• 2002

관상어 초기자어 사육은 rotifer 개발 전 단계의 달걀 노른자를 갈아서 먹이는 방법에서 벗어나지 못하고, 반죽사료를 제작하여 공급하는 방식을 취하고 있는 실정이다. 그렇지만, 해산 어류의 자치어는 rotifer의 먹이생물로서의 가치가 밝혀진 이후 종묘생산에 있어서 없어서는 안될 정도로 중요한 위치를 차지하고 있다. 이에 해수산 종묘생산에서는 다양한 연구가 수행되고 있는데, 그 분야로는 먹이공급횟수, rotifer 공급밀도, 배합사료의 이용, 일일 섭식량(Gatesoupe and Robin, 1992) 및 소화시간(복소, 1997)등이 있다. (중략)

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2001.12a
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• pp.86-86
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• 2001

• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.340-346
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• 2023

The diet composition of Engraulis japonicus were studied using 1,087 specimens collected by set net fisheries and boat seine fisheries in the coastal waters of Tongyeong, Korea. The size of the specimens ranged from 1.9 to 14.7 cm in fork length. E. japonicus was fed mainly on Copepods, which constituted 50.4% of IRI, followed by Euphausiids, which constituted 47.3% of IRI. Graphical analysis of the diet composition showed that E. japonicus was specialist predator. The result of analysis in ontogenetic changes significantly exhibited among size classes (<8.0 cm, 8.0~10.0 cm, 10.0~12.0 cm, ≥12.0 cm). The proportion of Euphausiids increased, as body size of E. japonicas increased whereas the consumption of Copepods decreased. In the Spring, Autumn and Winter, the diet was dominated by Copepods. In the Summer, the diet was dominated by Euphausiids.

• Korean Journal of Ichthyology
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• v.20 no.4
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• pp.279-284
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• 2008

The feeding ecology of endangered Cottus hangiongensis was studied in the Hosan stream from September 2006 to August 2007 by collecting them seasonally. The stomach contents of C. hangiongensis consisted mainly of aquatic insects and Nematoda, small fish, fish eggs, snails (Semisulcospira libertina), and small stones were also observed. The main aquatic insects in the order of relative importance were Diptera, Trichoptera, Ephemeroptera and Plecoptera. The most important prey items were Chironomidae sp.1 and Hydropsyche kozhantschikovi. Change in the main prey organisms by season were Trichoptera in the spring and the summer, Diptera in the autumn, and Plecoptera in the winter by ratio of dry weight.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.247-252
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• 1995

To investigate the food organisms of the Japanese anchovy (Engraulis japonicus) during the first feeding stage, the gut contents of anchovy, captured in Kwangyang Bay at June 1990, were observed. Anchovies started to eat from 3.0mm (NL) after finishing to absorb the yolk. The food organisms were composed of copepod eggs and nauplii tintinnids, and etc. The major food organisms of the anchovy larvae of 3.0-3.8mm (NL) were copepod eggs and nauplii, whereas those of larvae longer than 3.8mm(NL) were only copepod nauplii.

• Korean Journal of Ichthyology
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• v.17 no.4
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• pp.258-263
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• 2005

Feeding habits of Hapalogenys mucronatus (10.1~22.1 cm) collected from coastal waters off Sori Island, Yeosu, from June 2003 to May 2004 were studied. H. mucronatus is a carnivore which consumes mainly caridean shrimp, crabs, polychaetes, and amphipods. Its diet includes small quantities of bivalves, cephalopods, seagrass, hermit crabs, isopods, eggs, mysids, gastropods, and copepods. H. mucronatus undergoes significant size-related changes; smaller fish (10~11.9 cm) prey mainly on amphipods, shrimps and bivalves, while the proportion of caridean shrimp increases with fish size (12~17.9 cm). The larger fishes (18~22.1 cm) eat caridean shrimps and polychaetes.

• Korean Journal of Ichthyology
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• v.21 no.3
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• pp.200-207
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• 2009

The feeding habits of Micropterus salmoides were investigated and two lakes, Lake Okjeong and Lake Yongdam, between March 2007 and March 2009. In Lake Okjeong, M. salmoides was likely introduced almost 20 years ago and in Lake Yongdam was less than 10 years ago. Food contents in M. salmoides from each lakes showed a significant difference in Index of Relative Importance (IRI) value. Fishes was most important prey item in Lake Okjeong whereas decapoda in Lake Yongdam. The difference in IRI of the Decapoda means that their abundance of this prey item in Lake Yongdam is higher than in Lake Okjeong. These decrease of the Decapoda in the lake may be caused by the feeding of M. salmoides. In Lake Yongdam the proportion of the Decapoda in the food of M. salmoides decreased during the study period, while the fishes increased from 2007 to 2008, suggesting related relationship to the feeding activity of M. salmoides as was seen in Lake Okjeong.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.10-17
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• 1999

Feeding Habits of Acanthogobius flavimanus collected from the eelgrass bed in Kwangyang Bay from January to December 1994 were studied. A. flavimanus was a carnivore which consumed mainly polychaetes, crabs, shrimps, gammarid amphipods and fishes. Its diets included small quantities of ophiuroids, gastropods, bivalves, caprellid amphipods, isopods and tanaids. It showed ontogenetic changes in feeding habits. Small individuals fed mainly on polychaetes and amphipods. While the consumption of polychaetes and amphipods decreased with increasing fish sin, the consumption of shrimps, crabs and fishes increased. A. flavimanus fed diverse prey organisms in adult stage. The relative proportion of the major prey items changed with season. Although the consumption of polychaetes, shrimps and gammarid amphipods was relatively high in spring and autumn, A. flavimanus fed various prey organisms in nearly equal proportions in the other seasons.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.413-422
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• 1997

To know the food chain of an intertidal community, feeding habits of Acanthogobius elongata were studied by analyzing stomach contents. A. elongata were monthly collected and the environment conditions of the habitat were investigated in the intertidal zone of Naecho-do, Kunsan from July 1993 to June 1994. Ratio of stomach contents to weight of A. elongata was $1.78\%$, and fullness of stomach showed a similar value to ratio of stomach contents to weight. Fullness of stomach was increased twice a day in the morning and the afternoon. The most important food item was copepods amounting to $54\%$ of the total stomach contents. Of these, Paracalanus parvus was most abundant in spring, Calanus sinicus in summer, Acartia sp. in autumn, and Calanus sinicus in winter. Degree of overlapping for the food items between seasons was not very high, except between spring and summer. There were little differences in feeding habits among the size groups. For all size groups of A. elongata, the occurrence rates of copepods, decapods, molluscs and cirriped larvae were high. As the fish grows, those of amphipods, polychaete larvae, isopods, cumaceans and stomatopods increased gradually. The importance index of the major food items was in the order of Calanus sinicus, Corycaeus affinis and Acartia sp..