• 제목/요약/키워드: Marine Fish

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음향 자료를 이용한 하계 여수 바다목장 해역에서 어군의 시·공간 분포와 특징 (The Characteristics and Spatio-temporal Distribution of Fish Schools during Summer in the Marine Ranching Area (MRA) of Yeosu using Acoustic Data)

  • 윤은아;황두진;김호상;이경선
    • 한국수산과학회지
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    • 제47권3호
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    • pp.283-291
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    • 2014
  • This study assessed dominant fish species, and the characteristics and spatio-temporal distribution of fish schools using acoustic and catch data in the marine ranching area (MRA) of Yeosu in July and August 2013. Acoustic data were collected using a 200-kHz dual beam transducer, and catch data were analyzed through auction data generated by a set net installed in the MRA. More fish schools were detected by acoustic methods in July than in August. The temporal distribution of fish schools differed between July and August, but, many schools demonstrated a high mean volume scattering strength (SV) around artificial reefs. Additionally, the characteristics of fish schools detected by echograms and the species caught by set nets differed between July and August. The dominant fish species were Engraulis japonicus, Pampus argenteus, Scomberomorus niphonius, and Pampus echinogaster in July, and approximately 85% of the catch in August consisted of Scomberomorus niphonius. Therefore, hydro-acoustic tools are useful for estimating fish school characteristics in large areas over a short period. To determine species, it is important to conduct net sampling surveys during the acoustic surveys. However, if a database of fish school characteristics organized by species is constructed through continuous study, it could be possible to identify fish species through acoustic methods alone.

Effects of Different Dietary Cadmium Levels on Growth and Tissue Cadmium Content in Juvenile Parrotfish, Oplegnathus fasciatus

  • Okorie, Okorie E.;Bae, Jun Young;Lee, Jun-Ho;Lee, Seunghyung;Park, Gun-Hyun;Mohseni, Mahmoud;Bai, Sungchul C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제27권1호
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    • pp.62-68
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    • 2014
  • This feeding trial was carried out to evaluate the effects of different dietary cadmium levels on growth and tissue cadmium content in juvenile parrotfish, Oplegnathus fasciatus, using cadmium chloride ($CdCl_2$) as the cadmium source. Fifteen fish averaging $5.5{\pm}0.06$ g (mean${\pm}$SD) were randomly distributed into each of twenty one rectangular fiber tanks of 30 L capacity. Each tank was then randomly assigned to one of three replicates of seven diets containing 0.30 ($C_0$), 21.0 ($C_{21}$), 40.7 ($C_{41}$), 83.5 ($C_{83}$), 162 ($C_{162}$), 1,387 ($C_{1,387}$) and 2,743 ($C_{2,743}$) mg cadmium/kg diet. At the end of sixteen weeks of feeding trial, weight gain (WG), specific growth rate (SGR) and feed efficiency (FE) of fish fed $C_{21}$ were significantly higher than those of fish fed $C_{83}$, $C_{162}$, $C_{1,387}$ and $C_{2,743}$ (p<0.05). Weight gain, SGR and FE of fish fed $C_0$, $C_{21}$ and $C_{41}$ were significantly higher than those of fish fed $C_{162}$, $C_{1,387}$ and $C_{2,743}$. Protein efficiency ratio of fish fed $C_0$, $C_{21}$ and $C_{41}$ were significantly higher than those of fish fed $C_{1,387}$ and $C_{2,743}$. Average survival of fish fed $C_0$, $C_{21}$, $C_{41}$ and $C_{162}$ were significantly higher than that of fish fed $C_{2,743}$. Tissue cadmium concentrations increased with cadmium content of diets. Cadmium accumulated the most in liver, followed by gill and then muscle. Muscle, gill and liver cadmium concentrations of fish fed $C_0$, $C_{21}$, $C_{41}$ and $C_{83}$ were significantly lower than those of fish fed $C_{162}$, $C_{1,387}$ and $C_{2,743}$. Based on the ANOVA results of growth performance and tissue cadmium concentrations the safe dietary cadmium level could be lower than 40.7 mg Cd/kg diet while the toxic level could be higher than 162 mg Cd/kg diet.

해상 가두리 양식장 암모니아 모니터링 시스템 개발 (Development of the Monitoring System for Ocean Fish Farm)

  • 오진석;조관준;곽준호;진선호;이종호
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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    • pp.273-274
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    • 2006
  • The sea is origin of all lift, and 90% of the all living organisms are in the sea. The biosynthesis is very different. Many organisms are kept on a lower or developed to another evolutionary level than on shore. Our society is increasing demand and need for marine food and this food has to product at onshore or offshore fish farming sites. Ocean fish farms have a special operation properties such as a good quality water, net cage, sheltered locations and feeding system. The farming site is controlled and monitored for fish welfare as ammonia($NH_3$), temperature, the speed of a running fluid. Specially, the fish farm is seriously influenced by ammonia. In this paper, $NH_3$ monitoring system for ocean fish farm is researched for the suitable fish farming sites, and test equipment is designed for achieving practical data. The equipment wit monitoring algorithm is expected to the useful system for ocean fish farm.

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Comparative analysis of sectioned-body morphometric characteristics of diploid and triploid marine medaka, Oryzias dancena

  • Park, In-Seok
    • 환경생물
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    • 제38권1호
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    • pp.137-145
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    • 2020
  • The sectioned-body morphometric characteristics of the diploid and triploid marine medaka, Oryzias dancena, of both sexes were examined to collect basic data on the significant differences between the diploid and triploid fish. Significant differences between the diploid and triploid fish in both sexes were observed in the body circumference anterior to the base of the pelvic fin, the body circumference anterior to the base of the anal fin, the body circumference anterior to the base of the dorsal fin, the area anterior to the base of the pelvic fin, the area anterior to the base of the anal fin, the area anterior to the base of the dorsal fin, the total height anterior to the base of the pelvic fin, the total height anterior to the base of the anal fin, the height anterior to the base of the pelvic fin, the height anterior to the base of the anal fin, the width anterior to the base of the anal fin, the belly thickness II anterior to the base of the anal fin, section shape 2-1, and section shape 4-1 (p<0.05). These measurements were greater in the triploid marine medaka of both sexes than those in the diploid marine medaka of both sexes, and they were also greater in the male diploid and triploid marine medaka than those in the corresponding female fish. Therefore, the sectioned-body morphometric dimensions were greater in the triploid males than those in the triploid females and the diploid fish in this study.

통영 바다목장해역에 서식하는 조피볼락(Sebastes schlegeli)의 식성 (Feeding Ecology of Sebastes schlegeli in the Tongyeong Marine Ranching Area)

  • 박경동;강용주;허성회;곽석남;김하원;이해원
    • 한국수산과학회지
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    • 제40권5호
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    • pp.308-314
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    • 2007
  • The feeding habits of Sebastes schlegeli collected from the Tongyeong marine ranching area throughout 2002 were studied. S. schlegeli is a carnivore (piscivore), and consumed mainly fish. Its diet also included a small amount of caridean shrimps, crabs, amphipods, polychaetes, and isopods. The diet of S. schlegeli underwent size-related changes. Small individuals (standard length (SL)<6 cm) fed mainly on fishes, caridean shrimps, and amphipods, and the proportion of fish increased with SL. Large individuals (SL>20 cm) ate fish predominately. The diet of S. schlegeli changes seasonally, and caridean shrimps were consumed mainly from May to July. The dietary breadth index of S. schlegeli varied with SL and season.

아산만해역 어류체내와 퇴적물중의 PCB와 유기염소계농약 분포 (On the Distribution of PCBs and Organochlorine Pesticides in Fish and Sediment of the Asan Bay)

  • 최진영;이성규;방재현;양동범;홍기훈;신경훈
    • Ocean and Polar Research
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    • 제33권1호
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    • pp.45-53
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    • 2011
  • Distribution of Polychlorinated biphenyls (PCBs) and organochlorine pesticides in sediments, seawater and fish tissues were examined. Concentrations of ${\Sigma}PCBs$ and ${\Sigma}DDTs$ in the intertidal sediments of Asan Bay ranged from $1.90{\sim}3.27\;ng\;g^{-1}$ dw (dry weight) and $0.51{\sim}1.26\;ng\;g^{-1}$ dw, respectively. ${\Sigma}PCBs$ concentrations in the tissue of greenling (Hexagrammos otakii), olive flounder (Paralichthys olivaceus) and finespotted flounder (Pleuronichthys cornutus) were $1.27{\pm}0.55$, $1.30{\pm}0.71$ and $1.19{\pm}0.43\;ng\;g^{-1}$ ww (wet weight), respectively. The profile of PCBs in the sediments and the 3 species of fish differed as witnessed by the dominance of tetra- to penta-chlorinated congeners in sediments while penta- to hexa-chlorinated congeners dominated in fish. ${\Sigma}DDTs$ concentrations were $0.67{\pm}0.52$, $0.79{\pm}0.61$, $1.58{\pm}1.05\;ng\;g^{-1}$ ww respectively in the tissue of greenling, olive flounder and finespotted flounder. The p,p'-DDE appeared to be the most important metabolite of DDT in studied fishes. The concentrations of PCBs and organochlorine pesticides measured in this study for fish were generally lower than those of previous studies. Compared to the pollutant concentration quality guidelines in marine fish, the environment of Asan Bay appears to be in a healthy state.

생물다양성 특성 분석을 통한 우리나라 주변 해양생태계 변화 연구 (A study on the variation of the Korean marine ecosystem through biodiversity attributes)

  • 이종희;서영일;윤상철;강희중;최지훈;최민제;김진우
    • 수산해양기술연구
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    • 제59권4호
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    • pp.315-327
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    • 2023
  • In the last five decades, there has been a consistent decline in the total catch of fisheries in the Korean jurisdiction since the peak in 1986. The decline in catch slowed and slightly rebounded in the 2000s, but changed back to a decline in the 2010s. As indicators that can identify changes in the marine ecosystem, trophic level (TL), biodiversity index (H'), and the ratio between pelagic fish and demersal fish (P/D) were analyzed by each local marine ecosystem. There were some different changes in each local marine ecosystem, but the mean TL and H' decreased and P/D increased in general in Korean waters. Demersal fish, which were dominant in the 1970s and 1980s, declined, and small pelagic fish and cephalopods have dominantly changed since the 1990s. However, these changes are not simple, and they are fluctuating in complex ways relating to each marine ecosystem and the timing. It is believed that changes in marine ecosystems in Korean waters are likely caused by a combination of fisheries and climate change. The ecosystem indicators reflected a change in the total catch, a sharp drop in catch of demersal fish, and increasing catch of pelagic fish since the mid-1980s.

거문도 주변 해역에 출현하는 저어류 군집의 종조성 (Species composition of the demersal fish assemblage in the coastal waters off Geomun island, Korea)

  • 김신곤;장충식;안영수;고은혜;백근욱
    • 수산해양기술연구
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    • 제50권2호
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    • pp.131-138
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    • 2014
  • The study aims at analyzing a species composition of the fish live in bottom of the coastal waters off Geomun island, Korea. To reach the goal of the study, a species composition and it's monthly fluctuation, a monthly fluctuation of the dominant species and it's appearance type was analyzed the fishes caught by the bottom trawl. The result obtained can be summerrized as follows; Fish caught in this area composes 14 orders, 34 families, and 47 species. The largest number of fish species was Perciformes (15 families and 19 species). The most dominant species in an number of fish was jhon dory, Zeus faber which was occupied at 22.5% from the whole number, the second most dominant species was horse mackerel, Trachurus japonicus which was occupied at 21.2%. Four groups were categorized based on appearance time period.

경남 한산도 봉암 잘피밭 어류의 월별 종조성 변화 (Species Composition of Fish Assemblage in Eelgrass Bed of Bongam on Hansando Island, Korea)

  • 한동훈;이대희;박준수;김준섭;이용득;박종율;곽우석
    • 한국어류학회지
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    • 제29권2호
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    • pp.130-138
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    • 2017
  • 경남 통영시 한산면 추봉리 봉암에 위치한 잘피밭의 어류의 월별 종조성과 양적 변동을 분석하였다. 자료는 2009년 8월부터 2010년 7월까지 매월 예인망을 이용하여 수집하였다. 총 30종, 3,237개체, 6,850.1 g의 어류가 채집되었다. 우점한 종들은 살망둑, 그물코쥐치, 복섬, 점망둑, 일곱동갈망둑, 실고기로 전체 개체수의 86.7%를 나타내었다. 잘피의 평균 엽장은 8월에 $772.7{\pm}136.0mm$, 건중량 81.6 g, 11월 평균 엽장은 $698.1{\pm}146.4mm$, 건중량 57.2 g, 2월 평균 엽장은 $499.2{\pm}96.4mm$, 건중량 15.41 g, 5월의 평균 엽장은 $642.5{\pm}208.3mm$, 건중량 61.90 g이었다. 봉암 잘피밭 어류 군집은 9월부터 12월까지 종수와 개체수가 감소하다가 그 이후부터 증가하였다. 이러한 결과는 계절변화에 따른 수온 변화가 잘피밭의 어류 종조성에 주요한 영향을 주었기 때문인 것으로 생각된다.

세존도 주변해역에 출현하는 저어류 군집의 종조성 (Species composition of the demersal fish assemblage in the coastal waters off Sejon island, Korea)

  • 고은혜;안영수;백근욱;장충식
    • 수산해양기술연구
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    • 제51권4호
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    • pp.630-636
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    • 2015
  • The study aims at analyzing a species composition of the fish live in bottom of the coastal waters off Sejon island, Korea. To reach the goal of the study, a species composition and it's seasonally fluctuation, a seasonally fluctuation of the dominant species and it's appearance type were analyzed with the fishes caught by the bottom trawl in the coastal waters off Sejon island from May, 2011 to March, 2012. The results obtained can be summarized as follows; Fish caught in this area composes 10 orders, 25 families, and 37 species. The most dominant species in an number of fish was Pennahia argentata which was occupied at 42.1% from the whole number, the second most dominant species was Konosirus punctatus which was occupied at 14.2%. The most dominant species in a biomass of fish was Pennahia argentata which was 31.3% out of the whole catch, the next dominant species was Lophius litulonwhich which was 18.2%. The first group (Trichiurus lepturus, Zeus faber, Pennahia argentata, Chelidonichthys spinosus and Lophius litulon) was appeared at May, August, October, the second group (Sphyraena pinguis) was appeared at May and November, the third group (Pampus argenteus) was appeared at August, the fourth group (Pampus echinogaster, Leiognathus nuchalis, Konosirus punctatus and Engraulis japonicus) was appeared at March.