• 한국수산과학회지
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• 제40권1호
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• pp.24-30
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• 2007

We developed an ecosystem indicator (EI) for the coastal and offshore areas of Korean waters. One of the major scientific challenges of this undertaking was to translate broad policy statements for ecosystem-based fisheries management (EBFM) into practical terms. Fish reproduction potential (FRP) was defined as an EI to describe the reproductive probability of adult fisheries resources in Korean waters. The FRP was estimated as the ratio of adult fish composition to total catch, catches (in metric tons) by species and by ecosystem, and fishery effort (in horse power per metric ton). The FRP indices of the East/japan Sea Ecosystem (EJSE), Yellow Sea Ecosystem (YSE), and East China Sea Ecosystem (ECSE) began to decrease after the mid-1980s, and the current indices have decreased further, at 0.63 (EJSE), 1.22 (YSE), and 0.68 (ECSE) index points compared to the indices of 1975, when similar catch amounts were recorded. Lower FRPs in the Korean marine ecosystems were the result of higher proportion of immature fisheries resources in the total catch. Because this kind of ecosystem-level indicator is thought to reflect scientific approaches to EBFM and to provide an important tool for assessing the current status of marine ecosystems with respect to both quantity and quality, more EIs should be developed for Korean waters.

• 한국해양학회지:바다
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• 제6권3호
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• pp.164-179
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• 2001

1991년부터 1994년 사이에 한국 근해에서 대형선망에 어획된 수산생물의 종조성, 어획량, 분포의 계절 및 연 변동 양상을 파악하였다. 조사 기간 중 전체의 0.1%이상을 차지하는 주요 종은 19종이 출현하였으며, 그중 고등어(Scomber japonicus)가 전체 생체량의 54.7%, 정어리 (Sardinops melanostictus) 20.4%, 전갱이 (Trachurus japonicus) 9.1% 그리고 삼치(Scomberomorus niphonius) 6.2%로 이들 부어류 4종이 전체의 90% 이상을 차지하였다. 어획노력량은 봄부터 높아져 여름에 최고였고 가을철까지 높았으나, 단위노력당 어획량은 가을부터 높아져 겨울에 최고를 보였고 봄까지 높게 나타났다. 이는 산란과 섭이를 위해 남북 이동을 하여 여름동안 분산되었던 부어류가 겨울철에는 월동장으로 회유하여 위집됨으로써 어획률이 높았기 때문으로 판단된다.

• 수산해양기술연구
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• 제55권2호
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• pp.95-104
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• 2019

This study is aimed to take a stock assessment of blackthroat seaperch Doederleinia seaperch regarding the fishing effort of large-powered Danish Seine Fishery and Southwest Sea Danish Seine Fishery. For the assessment, the state-space model was implemented and the standardized catch per unit effort (CPUE) of large powered Danish Seine Fishery and Southwest Sea Danish Seine Fishery which is necessary for the model was estimated with generalized linear model (GLM). The model was adequate for stock assessment because its r-square value was 0.99 and root mean square error (RMSE) value was 0.003. According to the model with 95% confidence interval, maximum sustainable yield (MSY) of Blackthroat seaperch is from 2,634 to 6,765 ton and carrying capacity (K) is between 33,180 and 62,820. Also, the catchability coefficient (q) is between 2.14E-06 and 3.95E-06 and intrinsic growth rate (r) is between 0.31 and 0.72.

• 수산해양기술연구
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• 제40권4호
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• pp.295-303
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• 2004

한국 거문도 연안에서 시설된 세라믹 어초의 시설 효과를 구명하기 위하여 2001년부터 2003년까지 어초 시설구, 자연초구 및 비시설구 어장에서 삼중자망에 의한 어획량과 어획종을 조사하였다. 어초 시설구에서의 폭당 어획량은 1,621.9g으로 자연초구와 비시설구에 비해 각각 67.9%, 333.3%많았는데, 이를 Tukey test로 검정한 결과, 어초 시설구와 자연초구에서는 유의차가 없었으며, 어초 시설구와 비시설구와는 유의차가 인정되었다.(p<0.05). 어초 시설구에서 어획된 월 평균 종수는 7.2종으로 자연초구에 비해 7.1% 적었던 반면 비시설구보다 97% 많았는데, ANOVA 분석결과 유의차가 없었다. 어초 시설구의 어획률은 11월에 최대, 5월에 최소치를 보였으며, 이러한 현상은 자연초구, 비시설구에서도 나타났다. 어초 시설구의 우점종은 참동, 말쥐치, 쥐치, 도다리, 거북복 등 암초성이 강한 저서어종이었고, 자연구와 비시설구에서는 저서성 및 회유성 어종이 혼재하였다.

• 수산해양교육연구
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• 제28권2호
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• pp.539-549
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• 2016

This study analyzed ship's passing characteristics in relation with incoming and outgoing routes in Yeosu Gwangyang Port, and examined the risk factors and measures for safety management of marine traffic. The number of passing ships in Yeosu Gwangyang Port was about 60,000 ships annually based on 2014, and the tonnage rose 73% from 447,000 thousand tons in 2005 to 770,000 thousand tons in 2014. Actually, the number of large passing ships was revealed to enormously increase. As a result of marine traffic survey in Yeosu Gwangyang Port for three days in August 2015, daily average passing ships were 408 ships, and 77% of the total passing ships passed between 04:00 and 20:00. The chemical ships and general cargo ships took up the most at 58% of the total incoming and outgoing ships, followed by other work ships at 21%, tankers at 8%, fishing vessels at 7.5% and container ships at 5.5%. Concerning the size of passing ships, ships less than 1,000 tons accounted for 58.6% of the total passing ships. Ships of 1,000-5,000 tons were 20.1%, and those of 5,000-10,000 tons were 6.8%, and more than 10,000 tons were 14.4%. Especially, ships of 500 tons and less using mainly coastal passing routes took up 49% of the total passing ships. As for ship's passage ratio by route, Nakpo sea area where many routes meet accounted for 27.2%, specified area 49%, costal route 8%, specified area's incoming and outgoing sea area around Daedo 4.5%, and Dolsan coastal ara and Kumhodo sea area 8.5%. The number of ships standing by for anchoring in the six designated anchorages was 230 for three days. The standby rate for anchoring was 25% based on the specified area passing ships. In Nakpo sea area, where many routes meet, parallel passing and cross passing between ships occurred the most frequently. In the specified area, many cases, in which incoming and outgoing cargo ships at the starting and ending parts and incoming and outgoing work ships and fishing vessels at the coastal routes cross, took place. Consequently, the following measures are urgently needed: active passing management in the Nakpo sea area, where passing routes are complex, specified areas and costal traffic routes, the elimination of rocks in the route close to Myodo, an effort to improve routes including shallow depth area dredging, and rational safety management for small work ships frequently incoming and outgoing the passing routes of large ships, and fishing vessels operated in the sea areas around those passing routes.

• 수산경영론집
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• 제46권2호
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• pp.31-41
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• 2015

This study aimed to analyze the relationship between sea surface temperature as a climatic element and catch amount of offshore and coastal fisheries in Korea using annual time series data from 1970 to 2013. It also tried to predict the future changes in catch amount of fisheries by climate change. Time series data on variables were estimated to be non-stationary from unit root tests, but one long-term equilibrium relation between variables was found from a cointegration test. The result of Granger causality test indicated that the sea surface temperature would cause directly changes in catch amount of offshore and coastal fisheries. The result of regression analysis on sea surface temperature and catch amount showed that the sea surface temperature would have negative impacts on the catch amount of offshore and coastal fisheries. Therefore, if the sea surface temperature would increase, all other things including the current level of fishing effort being equal, the catch amount of offshore and coastal fisheries was predicted to decrease.

• 수산해양교육연구
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• 제27권6호
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• pp.1745-1754
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• 2015

This study aimed to analyze the relationship between sea temperatures and anchovy catch of Anchovy drag net fishery using annual time series data from 1970 to 2013. In the analysis, time series data on variables (CPUE, sea surface temperature, and 10m temperature) were estimated to be non-stationary from unit root tests, but one long-term equilibrium relation among variables was found from a cointegration test. From an exclusion test, a 10m temperature would not have relations with CPUE and sea surface temperature. The result of regression analysis on sea surface temperature and anchovy catch indicated that the sea surface temperature would have positive impacts on the anchovy catch. It means that when the sea surface temperature would increase, all other things including the current level of fishing effort being equal, the catch of anchovy was predicted to increase. More specifically, the result showed that when 1% of sea surface temperature increases, CPUE would be increased by 2.81%.

• 한국수산과학회지
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• 제44권4호
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• pp.397-402
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• 2011

We surveyed the bycatch and discard of the shrimp-pot fishery in Hokkaido, Japan, three times during the major fishing period in September 2005. The surveyed catches were analyzed to separate bycatch, discard, and landings. To analyze bycatch and discard, we randomly selected 2 shrimp pots from each of 7 sets, for a total of 14 pots per survey. The total bycatch and discards from the rest of the shrimp pots were also analyzed in each survey. The total catch averaged 12 species. Coonstripe and pink shrimp catches averaged 74.7 kg/haul and 12.7 kg/haul, respectively. The weight of the bycatch averaged 33.4 kg/haul. The bycatch consisted mainly of snail fishes(5.1%), brittle stars(5.0%), and short-spined sea urchins(4.1%). Our analysis showed that the ratio of discard was 0.38, the rate of the discard was 27.4%, and the discard per unit effort was 33.4 kg/haul. The Hokkaido shrimp-pot fishermen discarded all of the bycatch except shrimps. Hence, the weight of the bycatch was equal to the weight of the discard. Our results comprise preliminary data that can be used to find ways to reduce bycatch and discard in the shrimp-pot fishery.

• 한국수산과학회지
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• 제42권3호
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• pp.297-301
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• 2009

The water temperature from 1980 to 2000 and the anchovy catch from 1990 to 2000 in the southeastern portion of the South Sea of Korea were used to illustrate the influence of water temperature on the catch of the anchovy, Engraulis japonica. 1993 and 1998 were selected as poor and good fishing years therefore, the horizontal and vertical distribution of water temperature and catch per unit effort in these years was compared. When the anchovy catch was lower, the water temperature at 10 m was also about $0-2^{\circ}C$ lower than during a normal year, which resulted in the formation of a weak thermocline. Conversely, when the anchovy catch was higher, the water temperature at 10m was $0-2^{\circ}C$ greater than during a normal year, which resulted in the formation of a strong thermocline at around 20 m.

• 수산경영론집
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• 제35권1호
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• pp.1-22
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• 2004

Since the red grouper stock was initially declared to be overfished by the NMFS in September 2002, the Gulf of Mexico Fishery Management Council must prepare for the red grouper rebuilding plan considering the following alternative management policies: Total Allowable Catch(TAC), 5 - month season closure, 1800 - pound trip limit, and 50 - fathom longline boundary. The first concern the Council has is to evaluate the effects of recommended policies and the second is to analyze the impact of management policies on yellow edge grouper. This is because the fleets harvest red grouper also catch yellowedge grouper, the regulations on red grouper are likely to allow fishing effort to be distributed into yellowedge grouper. Therefore, this study is aimed at evaluating the biological and economic effects of management policies considering simultaneously the impact of red grouper regulations on yellow edge grouper by developing a combined red grouper and yellowedge grouper bioeconomic model. The overall results indicate that management policies for red grouper would adversely affect the yellowedge grouper stock if yellowedge grouper is not protected by its regulations. The TAC policy has the most serious impact on the yellowedge grouper stock, while the 1800 - pound trip limit policy minimizes the reduction in the yellowedge grouper stock. However, the target stock size of red grouper is achieved as well as the largest net present value of returns is gained in the TAC policy.