• 수산해양기술연구
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• 제55권3호
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• pp.233-242
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• 2019

Species composition and yearly variation of fish eggs and larval fishes were investigated from 2014 to 2016. During the study period, the fish eggs were identified as belonging to 14 taxa. The dominant species of fish eggs were Leiognathus nuchalis, Engraulis japonicus, and Konosirus punctatus. These three species accounted for 97.4% of the total number of individuals collected. The collected larval fishes were identified into 37 taxa, 22 families, and seven orders. The dominant species of larval fish were Leiognathus nuchalis, and Gobiidae fishes. These three species accounted for 85.4% of the total number of individuals collected. The diversity index of the larval fishes was the highest in 2014 (H' = 1.60) and the lowest in 2015 (H' = 1.15). The evenness index was the highest in 2016 (J = 0.51) and the lowest in 2015 (J = 0.39). The dominance index was the highest in 2015 (D = 83.5%) and the lowest in 2016 (D = 70.9%). In addition, the economically important species in this area were Engraulis japonicus, Konosirus punctatus, Hippocampus coronatus, Sebastes schlegelii, Acanthopagrus schlegeli, and Cynoglossus joyneri.

• 수산해양기술연구
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• 제48권3호
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• pp.284-292
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• 2012

Species composition and abundance of larval fishes in the coastal waters off Gori in the southeastern Korea were investigated from January to December in 2006. During the study period, 32 larvae species belonging to 20 families were collected. The dominant species were Engraulis japonicius, Hexagrammos agrammus, Sillago japonicus, Acropoma japonicum, Apogon lineatus, and Konosirus punctatus. These six species accounted for 87.0% of the total number of individuals collected. The number of species, number of individuals, and species diversity indices fluctuated by season. The peak numbers of species and individuals occurred in July and May, respectively. Correlation analysis showed that monthly variations in water temperature and salinity could act as an indicators of seasonal variations in the larval fish community structure and abundance of the dominant species; in particular, the abundance of S. japonicus, A. japonicum, and A. lineatus were significantly corrected with the water temperature.

• 한국어류학회지
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• 제27권2호
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• pp.104-115
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• 2015

2010년 9월부터 2011년 8월까지 매월 소조기에 낙동강 하구역의 안쪽과 바깥쪽 두 개 정점에서 자치어를 채집하여 종조성의 시공간 분포를 밝혔다. 연구기간 동안 출현한 자치어는 총 7목 26과에 속하는 43개 분류군이 출현하였으며, 망둑어과 자치어가 전체 개체수의 63.1%를 차지하여 가장 우점하였다. 그중 하계 출현 망둑어과 자치어가 개체수비 55.5%로 가장 많이 채집되었다. 그 다음으로 청어 (13.2%), 멸치 (13.0%), 그리고 춘계 출현 망둑어과 자치어 (4.6%), 전어 (3.8%), 동계 출현 망둑어과 자치어 (3.1%), 정어리 (1.2%), 웅어 (0.7%) 순으로 채집되었고, 이들 8개 분류군이 전체 자치어 출현량의 95.0%를 차지하였다. 본 연구에서 출현한 자치어 군집은 총 5개의 그룹으로 구분되었으며, 시기적으로 봄, 여름 및 가을, 그리고 겨울 그룹으로 분리되었다. 특히 여름 및 가을에 자치어 군집의 공간적 분리가 나타났다. 하구역의 안쪽 정점에서는 하계 출현 망둑어과 자치어가 우점하였으며, 바깥 정점에서는 망둑어류 외에 멸치가 우점하였고, 기타 다양한 해수어종의 자치어가 출현하였다.

• 수산해양기술연구
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• 제54권1호
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• pp.81-88
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• 2018

A study for species composition and abundance of the fish assemblages in the eastern Jinhae Bay, Korea was conducted using monthly larval collection by a RN80 net from October, 2010 to September, 2011. Of all the 45 species collected, the dominant species were Clupea pallasii, Hexagrammos otakii, Pholis fangi and Engraulis japonicus. Clupea pallasii, Hexagrammos otakii, Pholis fangi in winter and examined Engraulis japonicus, Acanthogobius sp., Parablennius yatabei, and Tridentiger trigonocephalus in summer appeared seasonally. Popoulation characteristic by stations was not clear seasonally and spatially, and appearance aspects of dominant species were similar by stations. Compared our results with other studies in the South Sea, dominant species and their appearance period were similar to their spawning period. Finally, the appearance period of the larvae in the South Sea was closely resulted to spawning period rather than the regional characteristic.

• 한국어류학회지
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• 제31권3호
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• pp.159-164
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• 2019

이 연구는 여수시와 남해군 연안에서 2017년부터 2018년까지 2년에 걸쳐 계절별로 총 8회 수집하였다. 연구기간 동안 7개의 조사지점에서 출현한 부유성 난은 총 6개 분류군으로, 우점종은 멸치, 주둥치, 전어였고, 이 3종은 총 개체수의 96%를 차지하였다. 연구기간 중 출현한 자치어는 총 5목 11과 17개 분류군으로 우점종은 멸치, 주둥치, 전어로 부유성 난과 같았으며, 이 3종은 총 개체수의 70%로 높은 비율이었다. 자치어의 다양성 지수는 여름에 가장 높았고(H'=1.78) 겨울에 가장 낮았다(H'=1.34).

• 한국수산과학회지
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• 제50권5호
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• pp.616-620
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• 2017

The feeding habits of post-larval Yatabe blenny Parablennius yatabei (2.0-9.8 mm SL) were examined on the basis of 158 individuals collected from June to October in the coastal waters of eastern Jinhae Bay, South Korea. Based on the index of relative importance (IRI), post-larval P. yatabei fed 94.4% on copepods and 5.6% on tintinnids. The preference of post-larval P. yatabei for copepods to other prey items results from ontogenetic changes. The dietary percentage of copepods increased as fish size increased and tintinnids became less important. The feeding rate of post-larval P. yatabei was consistent at all times of day.

• 한국어류학회지
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• 제26권1호
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• pp.42-49
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• 2014

조사기간 동안 총 4종의 부유성 어란과 24종의 자치어가 마산만에서 채집되었다. 어란의 우점종은 멸치 (Engraulis japonicus) 어란이었다. 그러나 자치어는 앞동갈베도라치 (Omobranchus elegan), 고등어 (Scomber japonicus), 문절망둑 (Acanthogobius flavimanus), 쥐노래미 (Hexagrammos otakii), 돛양태류 (Repomucenus sp.), Scartella cristata, 망둥어과(Gobiidae sp.) 순으로 우점하였다. 이들 7종은 전체 출현개체수의 78.5%를 차지하였다. 어란과 자치어는 시공간적으로 큰 변동을 보였다. 어란과 자치어의 현존량은 2007년 7월에 가장 높았으며, 2007년 2월에 가장 낮았다. 그리고 난자치어는 다른 정점에 비해 정점 5에서 현존량이 높았다. 어란과 자치어 현존량의 시간적 변화는 수온에 영향을 받았다. 부유성 어란과 자치어는 수심, 지형 등과 같은 물리적 환경 요인에 따라 좀 더 얕은 만 안쪽 정점과 깊은 만 외곽 정점 간 군집 차이를 보였다.

• 한국식품조리과학회지
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• 제32권5호
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• pp.656-663
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• 2016

Purpose: This study was aimed to compare the nutritional content of the life stages of Tenebrio molitor. Methods: Nutritional element analysis comprised 12 minerals, 18 amino acids, 4 vitamins, and 12 fatty acids in larval, pupal, and adult stages. Nutritional element content was expressed as a percentage of 100 g of sample and determined in raw and freeze-dried samples to assess the food value of the insect. Results: Moisture, crude protein, and crude fat contents in raw samples were 63.5%, 23.19%, and 3.96%, respectively. Moisture content was significantly higher in the adult stage than in larval and pupal stages, whereas crude fat and crude ash contents were lower. Mineral composition of the mealworm showed K, P, and Mg in decreasing order of content, with no differences among life stages. Total amino acid content increased from adult, pupal to larval stages, in order with each stage's growth, without difference in amino acid composition. Seventy-six to 78% of total fatty acid corresponded to unsaturated fatty acids, with oleic acid as the most abundant. In addition, fatty acid content was high in the adult stage, and clear differences were observed between life stages. Finally, vitamins B1 and B3 showed similar content between life stages, whereas vitamin B2 showed a higher content the adult than larval and pupal stages. A higher folate content was observed in pupal and adult stages than in the larval stage. Although freeze-dried samples showed a higher nutritional content than raw samples, both samples were similar in composition and content between life stages, suggesting the suitability of freeze-dried samples for use as food materials. Conclusion: These results may provide a basis for more diversified industrial applications of the Tenebrio molitor.

• 한국수산과학회지
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• 제53권4호
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• pp.530-537
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• 2020

This study compared the survival rates, growth, and fatty acid content of larval Pacific cod Gadus macrocephalus fed with rotifers raised on different enrichment diets. We used four commercial rotifer enrichment products (one domestic, ER1, and three imported, ER2, ER3 and ER4). Twelve 200-L tanks were used, with three replicates per treatment. Larvae were fed rotifers 3 times daily at a rate of 5 rotifers/ml/feeding from 7 to 21 days post-hatch. At the end of the feeding trial, the survival rate and total length of larvae fed ER3 were greater than those of larvae fed ER1, ER2, or ER4. ER3 had the highest proportions of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and polyunsaturated acid (PUFA). Partially reflecting this composition, larvae fed ER3 had the highest proportions of DHA and PUFA. These results show a positive effect of rotifer DHA and PUFA proportions on the survival and growth rates of Pacific cod larvae.

• 한국수산과학회지
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• 제48권4호
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• pp.498-506
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• 2015

We examined the feeding habits of larval Clupea pallasii using 148 specimens collected from December 2010 to April 2011 in the Nakdong River estuary, Korea. We found that larval C. pallasii [8.3-26.0 mm NL (notochord length)] are carnivorous, consuming mainly copepods, rotifers, cirripeds, and free-living flatworms (Macrostomida). Their diet also include small quantities of shrimp nauplii, tintinnids, cladocerans, and larval bivalves, among other food sources. To evaluate ontogenetic changes in dietary composition, we split larvae into four size groups: 8-12 mm, 12-16 mm, 16-20 mm, and > 20 mm NL. Rotifers were the most important prey items for the smallest group, but all other groups predominantly consumed copepods. The largest group frequently preyed on rotifers, cirripeds and flatworms, in addition to copepods. Larvae also showed bi-modal feeding, with peaks in the late afternoon and at midnight, wherein the mean number of prey per individual peaked at 1,800-1,900 h.