• 제목/요약/키워드: fisheries resources management

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First satellite tracking of a free-ranging spotted seal (Phoca largha) from the Baengnyeongdo Island

  • Hyun Woo Kim;Namgyu Uh;Seulhee Lee
    • Fisheries and Aquatic Sciences
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    • 제26권11호
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    • pp.669-677
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    • 2023
  • The spotted seal (Phoca largha) in the Yellow Sea has declined due to poaching and habitat destruction. To aid conservation efforts, Argos satellite tracking were used to monitor the movements of a free ranging spotted seal around Baengnyeongdo Island. The satellite-transmitting tag successfully attached to the seal provided 1,556 location data collected during 107 days. The seal mostly moved between two haul-out sites, Yeonbong Rock and Mulbeom Rock. From October 6th to December 12th, the seal stayed within a 7 km radius of Yeonbong Rock. However, as the signal was lost, it was not possible to identify when the seal started to migrate from Baengnyeongdo Island to winter breeding area. This study provide understanding into the habitat preferences and movement patterns of spotted seals around Baengnyeongdo Island, contributing to the conservation and management of this species. Further research with more individuals and different age groups is essential to understand their habitat preference and develop effective conservation measures for the spotted seal population in the Yellow Sea.

Density estimation of euphausiids and copepods by using a multi-frequency method

  • Woo Seok Oh;Geun Chang Park;Jung-Hwa Choi;Hyoung Been Lee;Kyounghoon Lee
    • Fisheries and Aquatic Sciences
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    • 제26권12호
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    • pp.689-697
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    • 2023
  • This study used a multi-frequency acoustic method to assess the density and spatial distribution of dominant zooplankton, euphausiids and copepods, which are representative species of the zooplankton immigrating the sea around Republic of Korea. Acoustic surveys were carried out in the East Sea and South Sea from June 16 to 29, 2017, using the research vessel Tamgu 20th from the National Institute of Fisheries Science. From the results of the acoustic survey, the distribution of euphausiids was relatively higher in the East Sea than in the South Sea. Additionally, although the distribution of copepods was low in all areas, they were abundant in certain areas in the East Sea and the southern area of the Jeju Sea. Euphausiid and copepod density was estimated to be 1.2 g/m2 (CV = 19.1%) and 2.8 g/m2 (CV = 23.5%), respectively.

제주도 김녕 연안해역의 방어 어장형성 특성과 자원생물학적 기초 연구 (Acharacteristics on the forming of fishing ground and population ecological study of Yellow tail, Seriola quinqueradiata, in the coastal waters off Gim-nyeong of Jeju Island, Korea)

  • 장대수;유준택;김병엽;이승종;권대현;구준호;안젬마;오임열
    • 수산해양기술연구
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    • 제46권4호
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    • pp.406-415
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    • 2010
  • The forming of fishing ground and the population ecological characteristics of yellowtail, Seriola quinqueradiata, in the coastal waters off Gim-nyeong of Jeju Island were investigated. The stock of yellowtail, Seriola quinqueradiata, between Jeju Island and coastal areas of the East Sea is probably the same. Water temperature probably is a major factor for controlling distribution of yellowtails in deeper, offshore areas off Jeju Island. However, the major factor that determines aggregation of yellowtails in coastal areas of Jeju Island, especially off Gim-nyeong is probably strong tidal currents driven by distribution of yellowtails rather than hydrological conditions such as Yellowtails collected off Jeju Island were from 1 to 4yrs old and about 50% of them were $1^{-yr}$ old, probably indicating overfishing. Jack mackerel was the major prey item for yellowtails off Gim-nyeong from October to March, suggesting concurrence of the two species.

Comparison of catches and species composition for flounders caught using gillnets, gillnets with supporting lines, and trammel nets

  • Park, Hae-Hoon;Millar, Russell B.;Park, Chang-Doo;Park, Seong-Wook;Lee, Sung Il;Bae, Bong-Seong;An, Heui-Chun;Cho, Sam-Kwang;Lee, Kyounghoon
    • 수산해양기술연구
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    • 제50권1호
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    • pp.1-11
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    • 2014
  • To compare the catches made using gillnets, trammel nets, and gillnets with supporting lines, several experiments were conducted with commercial vessels near Uljin and Pohang in Eastern Korea between July 2010 and May 2011. Two sets of 13 different nets were used, including 5 panels of gillnets and trammel nets each with stretched mesh sizes of 7.6, 9.1, 10.6, 12.1, and 13.6 cm and 3 panels of gillnets with a mesh size of 9.1 cm with supporting lines with different line spacing. The outer (stretched) mesh size of the trammel nets measured 51.5 cm. The target fishes of the fishing nets were various types of flounders. The catch rate of flounders was 50.7% of the total catch in weight. The total catch for all nets was 443.8 kg. The predominant species was pointhead flounder (Cleisthenes pinetorum). The total catch by trammel nets was 1.4 times that of the comparable gillnets. But more pointhead flounder were caught by gillnets than by trammel nets, though there was no significant difference. Fishermen catching the pointhead flounder in Korea said that there was no need to use trammel net to catch it; this was an unexpected finding compared to the findings of other flounder fisheries. The amounts of roughscale sole, brown sole, and blackfin flounder caught by trammel nets were greater than those caught by gillnets. The mean lengths (standard deviation) of blackfin flounder, pointhead flounder, brown sole, and roughscale sole were 21.0 (4.57), 22.9 (3.40), 24.7 (4.90), and 28.3 (5.43) cm, respectively; there were significant differences in mean length (p < 0.00001). Therefore, in order to catch flounder efficiently, the fishing nets and mesh size should be chosen according to the target species. One advantage of using supporting lines is that it prevents breakage by strengthening the material especially when utilized on a rough bottom. Catch by using gillnet with supporting lines was not greater than that by using trammel net for the conservation of fisheries resources.

기업적 해태양식경영의 성립조건에 관한 연구 (The Conditions of the Entrepreneurial Laver Culture)

  • 김연수
    • 수산경영론집
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    • 제15권1호
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    • pp.96-113
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    • 1984
  • It has been appeared since 1979 that the pattern of laver culture changes from household management to entrepreneurial management. The typical entrepreneurial laver culture management (ELCM) can be defined as a management by the floating aquaculturing method and mechanical processing system. Historical studies show that the ELCM could be operated only under the following condintions; \circled1 securing capital, labor and aquaculturing farm. \circled2 Leveling up of technology to combine these resources effectively. \circled3 Realizing its true value of products for good profits. In turning from household mangement to ELCM, there are some obstacles as follows ; \circled1 Uncertainty, which cannot maintein the merit of mass production because the object of laver culture is living in the sea. \circled2 Immaturity of management owing manly to the lower level of technology and scarcity of competent managers. \circled3 Social problems ; lack of aquaculturing farm, overpopulation in fishing villiage, side-job with agriculture etc. For these reasons, there has been household management with overlabor and underconsumption in fishing village. In order that ELCM can enter the stage of maturity, those problems should be solved. Because ef laver industrial inferiority, these can be solved by the support assistance of government. As the required conditions in ELCM are filled by the government policy, ELCM are increased recently in its numbers.

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해양환경영향평가 관련 협의에 의한 연안이용분석 (Analysis of Coastal Area Utilization by Consultation of Marine Environmental Impact Assessment Related-Systems)

  • 이대인;엄기혁;권기영;김귀영;윤성순;장주형
    • 환경영향평가
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    • 제17권2호
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    • pp.97-103
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    • 2008
  • This study presented politic proposals and diverse utilization-type in coastal areas by analyzing results of reviewed related-statements of marine environment during the one year period of 2007 by Marine Environmental Impact Assessment Center. Total of 358 cases were reviewed, which was a significant increase from 270 in 2006. Consultation on the utilization of sea areas (CUSA) accounted for the largest number of 165 (46.1%) and it was followed by 104 cases of environmental impact assessment (EIA) (29.0%) and 89 cases of prior environmental review (PER) (24.9%). As such, evaluation statements (EIA+PER) related to consultations of the Ministry of Environment accounted for approximately 54% of the entire cases reviewed. To analyze the overall results of reviewing marine-related evaluation statements, utilization and planning were conducted by 47.9%, 38.4% and 13.7% in the South Sea, West Sea and East Sea of Korea, respectively. In evaluation statements (EIA+PER), port construction, industrial complex construction, urban management plan and road construction took up most of the part by 40.9%, 20.2%, 10.4% and 7.3%, respectively. In terms of CUSA-statement, it was evaluated that consultations were mostly carried out on use and reclamation of public water surface in coastal areas and on sea aggregate extraction process in EEZ. The largest number of plans for coastal use were established for Jeollanam-do, followed by Gyeongsangnam-do, Chungcheongnam-do, Gyeongsangbuk-do and Gyeonggi-do. In particular, development plans were concentrated on Jeollanam-do and Gyeongsangnam-do with stable marine environment and outstanding view of the nature. In most cases, these regions are adjacent to the areas designated as a sea area for environmental management and fisheries resources protection zone. Therefore, conflicts exist between development and preservation. Also, rather than random development, more detailed marine environmental impact assessment, gathering of public opinions and politic harmony are essentially required. For efficient coastal management and environmentally sound and sustainable development, fulfilling consistent and transparent coastal policies as well as active and reliable decision making to center on coastal environment by management bodies will be important.

양식 환경이 강도다리, Platichthys stellatus의 혈액 생화학적 성상 및 lysozyme 활성에 미치는 영향 (Effects of aquaculture conditions on blood chemistry property and lysozyme activity of starry flounder, Platichthys stellatus)

  • 권문경;임한규;민병화;변순규;김이청;조병열
    • 한국어병학회지
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    • 제20권3호
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    • pp.281-289
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    • 2007
  • 어병세균인 Edwardsiella tarda, Vibrio ichthyoenteri, Streptococcus iniae의 강도다리에 대한 병원성, 염분농도가 어병세균의 성장 및 강도다리의 lysozyme 활성과 사육수온, 밀도가 강도다리에 미치는 영향을 조사하였다.연구 결과, E. tarda에 대해서는 병원성이 높았으나, V. ichthyoenteri와 S. iniae에 대해서는 항병력이 높았다.염분농도에 따른 균의 증식속도 조사 결과, E. tarda와 S. iniae는 저염분에서 증식속도가 빨랐으나, V. ichthyoenteri는 저염분에서 낮았으나, 유의적인 차이는 보이지 않았다. 저염분 사육에서 강도다리의 lysozyme 활성은 일반해수구에 비하여 다소 낮게 나타났으나 유의적인 차이는 보이지 않았다.사육수온, 밀도가 강도다리에 미치는 영향을 조사한 결과, 수온은 26℃ 이하, 밀도는 수조저면적의 100% 이하가 강도다리의 생리학적 성상 및 lysozyme 활성이 높게 나타났다.

연안개량안강망 어업의 어획성능 및 어획능력 추정 (Estimation of fishing power and fishing capacity on coastal stow net fishery in the Korean waters)

  • 김병관;이경훈;김도훈;이건호;안희춘;김성훈;양용수
    • 수산해양기술연구
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    • 제51권4호
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    • pp.583-591
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    • 2015
  • The coastal stow net (stow net hereafter) in Korea is one of the major fishing methods for yellow croaker (Larimichthys polyactis), ribbon fish (Trichiurus lepturus), and anchovy (Engraulis japonicus). In terms of energy efficiency, the stow net fishery is more competitive than towing fishing gears such as trawl gears. The fishing vessels in stow net fishery have consumed less fossil fuel and also have had less carbon dioxide emission into the atmosphere. however, the stow net fishery is necessary to be regulated due to its increased output of the fleet. Therefore, it is required for fisheries authorities to manage the fishing capacity or fishing power for the assurance of fishery's sustainability. For fisheries management authorities, it is necessary to quantify data related to fishing capacity and fishing power to deploy fishery policy in a sustainable way. In terms of data for decision-making, Data envelopment analysis (DEA) method was conducted to estimate fishing capacity. Fishing power index (FPI) was also applied to calculate relative fishing power to approach the problem in a quantitative way.

New Record of Scolecenchelys fuscogularis (Anguilliformes: Ophichthidae) Leptocephali from Korea, as Revealed by Morphological and Molecular Analyses

  • Ji, Hwan-Sung;Kim, Jin-Koo;Lee, Soo Jeong;Kimura, Seishi;Hibino, Yusuke
    • Fisheries and Aquatic Sciences
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    • 제18권1호
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    • pp.109-113
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    • 2015
  • Three leptocephali (22.2, 22.7, 56.0 mm in total length) collected from the East/Japan Sea were identified by morphological and genetic analyses as belonging to the genus Scolecenchelys (Anguilliformes, Ophichthidae). Morphologically, the specimens were characterized by 148-158 myomeres, 10 gut swellings, dorsal fin origin above middle of the body, and 6 postanal melanophores between the anus and the caudal margin. An analysis of an 849-base pair 12S rRNA sequence of mitochondrial DNA showed that sequences are concordant with those of adult Scolecenchelys fuscogularis (genetic distance = 0.001). Furthermore total number of myomeres is consistent with the total number of vertebrae in adult S. fuscogularis. This study provides the first description of the morphological characteristics of S. fuscogularis leptocephali and their variations with size. The Korean name of S. fuscogularis is "Ga-neun-mul-baem", established by Ji et al. (2012).