• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.4
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• pp.241-250
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• 2007

Fishes were caught by a bottom trawl in the Yeo-ja bay of Korea by every three month(March, June, September and December) and seasonal variation of abundance and species composition were studied in 2005. The catches were 1,187kg and were composed of 115 species with 20 hauls by 5 stations. The dominant species caught were Charybdis bimcaulata, Crangon hakodatei, Parapenaeus fissurus, Oratosguilla oratoria, and Thryssa purava. One hundred fifty species were identified as fish(38%), crustacea(20%), mollusca(4%) and others(38%) which including of Asterias amurensis. The amount of species was high in June and September and low in March and December. The diversity index(H') was about 1.2－2.5 and station similarity of fishes caught among the community was 0.009－0.230.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.45 no.2
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• pp.96-105
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• 2009

For an effective management of fisheries resources, we need fisheries informations necessary for the establishment of reasonable fishing effort and TAC distribution. We carried out fishing research using trammel nets in the coastal sea of Susan-port(Yangyang, Gangwondo, Korea) and Hupo-port(Uljin, Gyeongbukdo, Korea) and analyzed fishing power variation of the fishing gear in terms of species composition, condition and so on for both sites. A total of 29 species were caught with most dominant species of Hippoglossoides dubius followed by Pseudopleuronectes herzensteini, Lophius litulon and Alcichthys elongatus in Susan. The total number of species caught in Hupo was 37 species with most dominant species of Todarodes pacifius followed by Lophius litulon, Hexagrammos agrammus and Pseudopleuronectes herzensteini. CPUE of Susan fishing area per trammel net was 12.74 fish and 2.00kg on average, while it was 6.80 fish and 2.27kg on average for Hupo. The fishing power index for both sites was 1, placing the two fishing grounds in a same level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.1052-1057
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• 2021

The diet composition of common flying squid Todarodes pacificus was studied using 1,084 specimens collected through trawl and jigging from June 2018 to June 2020 in the East Sea of Korea. The mantle length (ML) of the collected individuals ranged from 13.6 to 31.1 cm. Todarodes pacificus is a carnivore. In the study area, T. pacificus was observed feeding mainly on fish and cephalopods, in addition to small quantities of crustaceans. The calculated trophic level value for T. pacificus was 4.10. Small individuals (ML, <18.0 cm) mainly fed on cephalopods, while intermediate (ML, 18.0-23.0 cm) and large (ML, ≥23.0 cm) individuals fed mainly on fish and occasionally on cephalopods. Overall, as the body size of T. pacificus increased, the mean weight of the consumed prey increased (one-way ANOVA, P<0.05).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.428-444
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• 2012

The species composition and seasonal variation of fisheries resources in Jinhae bay and Jinju bay, were studied using shrimp beam trawl through a year of 2010. During the study period, a total of 117 species were collected in Jinhae bay. Species included were 63 species in Pisces and 24 in Crustacea. And a total of 106 species were collected in Jinju bay. Species included were 57 species in Pisces and 31 in Crustacea. The dominant species were Zoarces gilli, Crangon hakodatei and Oratosquilla oratoria in Jinhae bay, and Crangon hakodatei, Leiognathus nuchalis and Charybdis bimaculata in Jinju bay. The samples were mainly grouped according to the location and season on the SOM. Group 1 with sample sites in Jinju bay, was characterized by high values of Parapenaeopsis tenella, Leiognathus nuchalis and Hexagrammos otakii. Group 2 with sample sites in April, were dominant Crangon hakodatei and Luidia quinaria. The samples in Group 3 were high values of Charybdis bimaculata and Pleuronichthys cornutus. Group 4 with sample sites in Jinhae bay, was characterized by high densities of Zoarces gilli and Pholis fangi. The dominant species, Crangon hakodatei, were catched egg-bearing females until June. Zoarces gilli and Leiognathus nuchalis were presented small size individuals during study period. It represented that study area is an important role in spawning and nursery ground for fisheries resources.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.45 no.4
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• pp.201-210
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• 2009

Cast fishing gear needs some time for fishing progress, and catches and their composition by submerged time can change by several cause. Therefore, it is very importance to study fishing capacity of fishing gear by submerged time. This study is to investigate catches and their composition of shrimp trap, that is used in the coastal of the East Sea, and to find the fittest lifting time of trap. Experimental term are September 2006 and August 2007, the location is the coastal of Oho, Goseong, Gangwondo, Korea and one hundred trap is used at each casting and lifting of gear. For convenience of description, survey of 2006 and 2007 are dented as experimental code 1 and 2, and submerged time 21hr, 43hr and 66hr are dented as code A, B and C. The result of obtained from the above approach are summarized as follows: Many Northern shrimps(Pandalus eous), dominated 96.36%, are only catched in experimental code A, and in code B and C, some of coonstripe shrimp(Pandalus hypsinotus) and few morotoge shrimp(Pandalopsis japonica) are catched. CPUE of code 1A, 1B and 1C per trap were 21.67g, 29.51g and 28.48g, and those of code 2A, 2B and 2C per trap were 25.44g, 32.93g and 33.36g. Therefore, 24.66% of catch increased according as submerged time passes from 1 day to 2 days, and almost no change of catch was to be -1.1%. Carapace length of code 1A, 1B and 1C were 23.77mm, 25.00mm and 25.57mm, and those of code 2A, 2B and 2C per trap were 23.83mm, 24.95mm and 25.45mm. Thus, the more submerged time is, the less catch of small fish is and the more catch of large fish is. Consequently, fit lifting time of shrimp trap is after 2 days, and if considered trouble of fishing gear and condition of catch, the fittest lifting time is the third successive day of casting date.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.2
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• pp.168-175
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• 2013

The feeding habits of the black-edged sculpin Gymnocanthus herzensteini were studied using 944 specimens collected from February 2011 to January 2012 in the coastal waters off Mukho, Gangwondo, Korea. The G. herzensteini ranged from 11.8 to 36.3 cm in total length (TL). The percentage of empty stomachs in G. herzensteini was 40.2%, and the main prey items were Pisces, Euphausiasea, and Macrura. The smallest size group (11.8-15.0 cm TL) consumed mainly Polychaeta and Amphipoda. The quantity of prey increased in proportion to sculpin size. The composition of prey items and feeding habits of G. herzensteini exhibited seasonal fluctuations, that is, the main prey items during spring were Euphausiasea, whereas those during other seasons were Pisces.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.4
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• pp.437-445
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• 2017

Distribution and composition of the seabed litters in the exclusive economic zone of the West Sea of South Korea including 18 sea-blocks were investigated using a bottom trawl gear of the R/V Tamgtu 20 (National Institute of Fisheries Science) from 24th April 2011 to 4th May 2012. Each trawl shot was conducted for an hour in each sea-block and the total trawl shots was 18. As a result, 325.6 kg of seabed litter in total has been collected. The quantity of the seabed litter was highest at No. 202 of the sea-block, close to the Heuksan-Do. The highest occupied sea material was plastic (83.1% of entire seabed litters), the second highest material was metal combined with plastic (10.6%), and glass (2.9%), metals (2.3%), vinyl (0.6%), cloth (0.4%) and wood (0.2%) in order. The origin of seabed litters was from fishing gear (89.0% of all seabed litters). Therefore, it could be assumed that most seabed litters were derived from the fishing activity for example fishing nets and ropes.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.3
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• pp.407-415
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• 2014

Fish was caught by a set net in Gwideok, Jeju island that was studied to determine monthly variation of species composition and catch from May 2005 to October 2006. Total catch was 54 species, 44,118 individuals, and 2,152,423.7 g during survey period. Dominant species were Trachurus japonicus and Siganus fuscescens that held 91.3% of total individuals and 71.3% of total abundance. The highest individuals and abundance of catch were in July 2005, and the lowest individuals and abundance of catch were in October 2006 and in October 2005, respectively. As the result, temporal change in abundance have corresponded with changing water temperature.

• Korean Journal of Ichthyology
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• v.32 no.1
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• pp.8-13
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• 2020

The feeding habits of oriental bonito (Sarda orientalis) were studied using 288 specimens collected in the coastal waters of Jeju Island, Korea from January to December 2015. Oriental bonito is pelagic piscivore that consumes mainly fishes especially Engraulis japonicus and Scomber japonicus. Its diet also includes small quantities euphausiids, amphipods and cephalopods. Oriental bonito showed ontogenetic changes in feeding habits. Although fishes were the primary food consumed by all size groups, the ratio of fishes was slightly increased as body size increase. There also was a significant relationships between mean prey number and weight according to size class and season.

• The Korean Journal of Malacology
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• v.26 no.1
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• pp.85-89
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• 2010

Distribution of Cephalopods was investigated in the Yellow Sea, Korea from February, 2006 to November, 2008. The species composition of cephalopods, consisting of 14 species and 19,789 individuals has been identified. The dominant species of the Yellow sea was Euprymna morsei. The dominant species of the northern part, middle part and southern part were Todarodes pacificus, Loligo spp. and Loligo beka.