Jae Hyeong Yang

Variations in species composition of demersal organisms caught by trawl survey in the East Sea

To examine species composition, abundance and biomass of demersal organisms in the East Sea, bottom trawlsurvey was conducted at 7 sea areas from 2005 to 2007. A total of 107 species were collected and werecomposed of 54 fish species, 16 crustacea, and 37 mollusks in the East Sea from 2005 to 2007. Yearlyabundance per area which caught by trawl survey in the East Sea from 2005 to 2007 ranged from a high of292,234inds./km

Age and growth of the sandfish, Arctoscopus japonicus in the East Sea of Korea

were investigated from samples of the eastern seadanish seine and gill net fishery in the East Sea of Korea from February, 2004 to December, 2007. Ages weredetermined from annuli in otoliths and annuli were formed between December and February once a year.Also, the main spawning period was estimated to be between December and January, thus rings wereconsidered to be annual marks. For the relationship between fork length and total weight, a multiplicativeerror structure was assumed because variability in growth increased as a function of the length. Therelationship between fork length and total weight were TW0.0083FL

Species Composition and Distribution of Trammel Net Catches in the Coastal Waters of Gangwon Province, Korea

동해는 북한한류가 대륙붕 연안을 따라 남하하고 남쪽에서 고 온고염의 대마난류가 대한해협을 통해 유입되어 약 37°N 부근 에서 강한 수온전선이 형성되어 기초생산력이 높고 다양한 먹 이생물이 번식하면서 동해 수산자원의 중요한 어장과 성육장 역할을 하는 중요한 해역이다(Kawai, 1991). 또한 수심이 깊고 해안선이 단조로운 해양환경적 특성을 가진 연안역은 수많은 해양생물의 산란과 성육장으로 이용되고 있어 어장으로서 가 치가 매우 높은 곳이다(Chun et al., 2004). 강원도 연안을 북부인 속초와 남부인 동해를 조사해역으로 구 분하였는데, 강원 북부해역은 북한 연안을 따라 내려오는 저온 저염의 북한한류의 영향을 크게 받으며, 100 m 이후 수심이 급 격하게 깊어지는 지형적 특성이 있고 상대적으로 강원 남부지 역에 비해 니질 퇴적물의 분포범위가 좁은 특징을 가지고 있다 (Choi et al., 2012). 반면 강원 남부해역은 표층과 중층은 북상 강원 연안에서 삼중자망에 의한 어획물의 종조성 및 분포특성 손명호·윤병선*·박정호·최영민·양재형

Development of artificial spawning seaweeds of the sandfish, Arctoscopus japonicus

began to attach the egg massto artificial spawning seaweeds when sea temperature dropped below 10in December, spawned heavilywhen it was around 8in January, and completed the behavior when it started to increase over 10inFebruary. The hatching period of eggs was estimated to be about 60 days. The middle position in artificialspawning seaweed had the highest number of egg masses and the diameter of the egg mass ranged from 25mmto 62mm. Based on the result for the effects, the artificial spawning seaweeds of

Age and Growth of Blackfin Flounder Glyptocephalus stelleri in the East Sea, Korea

Age and growth of Glyptocephalus stelleri in the East Sea of Korea were determined, from monthly samples of commercial catches, caught by the eastern sea Danish seine fishery in 2007. The annuli of G. stelleri are formed once a year, with the boundary between opaque and translucent zones forming in September. Relationships between total length (TL) and total weight (TW) were TW=0.002TL 3.392 (r 2 =0.970) for females and TW=0.002TL 3.335 (r 2 =0.961) for males. TLs at annuli formation in otoliths were backcalculated from the otolith-length relationship and were adjusted to von Bertalanffy growth curves to Lt=39.71(1 – exp (-0.152(t+1.156)) ) for females and Lt=32.16(1 – exp (-0.213(t+0.879)) ) for males. From the age of 3 yerars, females grew faster than males (P<0.05).

Maturity and Spawning of Lycodes tanakae in the Coastal Waters of the Middle East Sea

벌레문치(Lycodes tanakae)는 농어목(Percifomes) 등가시치 과(Zoarcidae)에 속하는 어종으로 우리나라에 6속 7종, 세계적 으로 약 46속 220여 종이 분포하는 것으로 알려져 있다(Kim et al., 2005). 벌레문치의 분포는 우리나라 동해 중부 이북, 일본 북부, 오호츠크해에 분포하며 수심 200-700 m의 넓은 범위에 서식하는 반저서성 어종이고(Choi et al., 2002), 자치어 시기는 비교적 낮은 수심에서 서식하다가 성장하면서 점차 깊은 수심 으로 이동하여 해저에 잠입하는 특성을 가지고 있다(Balanov et al., 2006; Saveliev et al., 2011). 또한 몸은 길고 후반부는 측 편으로 머리는 약간 종편이고, 머리와 배에는 비늘이 없으며, 전 장이 1 m까지 성장하는 것으로 알려져 있다(Kim et al., 2005). 벌레문치 연구는 일본 남서해에서 트롤에 의해 어획된 등가 시치류의 서식밀도와 체장분포에 관한 연구(Balanove et al., 2011), 일본 Primor’e 해역에서 벌레문치의 분포 및 생물의 일 부 특성에 관한 연구(Saveliev et al., 2011), 일본 타타르 해엽에 서 수심에 다른 서식밀도와 체장분포 등에 관한 연구(Saveliev et al., 2012)가 있으며, 국내는 등가시치아목 어류의 분류학적 재검토에 관한 연구(Kim and Kang, 1991), 한국산 등가시치아 목 어류의 분류학적 연구(Kim, 2005), 한국 동해안 벌레문치 근 육의 생화학적 구성(Lee et al., 2012), 벌레문치의 식성에 관한 연구(Choi et al., 2013) 가 되어 있을 뿐 벌레문치에 대한 생태 학적 연구는 국내외적으로 매우 미비한 실정이다. 벌레문치는 우리나라 동해안에서 동해구기선저인망과 연안 자망에서 연중 어획되고 있는 어종이고, “장치”라는 방언으로 불리어지면서 과거 어획 후 폐기되었던 어종이었으나, 점차 관심도가 높아지면서 상업적 가치가 증가하고 있다(NFRDI, 2012). 이는 우리나라의 연근해 어업자원의 감소현상에 의한 동해 중부연안 벌레문치(Lycodes tanakae)의 성숙과 산란 손명호·윤병선·박정호·최영민·이재봉·이해원·차형기·양재형*

Community Structure and Distribution Pattern of the Pleuronectiform Fishes in the Uljin Marine Ranching Area, Korea

To elucidate the variation of species composition, biomass and length distribution of flatfishes by the period and region in the Uljin marine ranching area, bottom trawl survey was investigated at the six stations from Feb. 2008 to Dec. 2010. During the survey period, a total 4 families 17 species in the Pleuronectiformes, average 69,158 and 5,625 were identified, in 2008 appeared in 14 species, average 25,798 and 2,333 and in 2009 appeared in 13 species, average 102,360 and 5,634 and in 2010 appeared in 14 species, average 75,704 and 8,632 . The individual dominant species, occupying over 10% of total individuals, was Pleuronectes herzensteini (20,811 ind., 30.0%), Hippoglossoides pinetorum (18,666 ind., 26.9%) and Glyptocephalus stelleri (13,499 ind., 19.4%) also the biomass dominant species, occuping over 10% of total biomass, was P. herzensteini (2,207 kg, 39.3%), Pleuronectes yokohamae (857 kg, 15.3%), H. pinetorum (761 kg, 13.5%), Kareius bicoloratus (677 kg, 12.1%). From the cluster and MDS analysis based on Bray-Curtis similarity matrix of fourth root transformed data of species number and individuals in the Uljin marine ranching area from Feb. 2008 to Dec. 2010 was divided into two different groups of the flatfishes community in 2008 and from Jan. to Apr. in 2009 and 2010 (Group A) and the pleuronectiform community in from May to Dec. in 2009 and 2010 (Group B). From the cluster and MDS analysis using the similarity of demersal organisms community among six stations, the Uljin marine ranching area was divided into two different groups of Group 1 (St. 1 and St. 3) and Group 2 (St. 2, St. 4, St. 5 and St. 6).

Stock Assessment and Optimal Catch of Blackfin Flounder Glyptocephalus stelleri in the East Sea, Korea

The blackfin flounder Glyptocephalus stelleri is a commercially important species in the East Sea of Korea, but its catches and biomass have decreased gradually in recent years. This study estimated the optimal catch (acceptable biological catch, ABC) for the effective management of this species by estimating population ecology parameters and the stock biomass of blackfin flounder in the East Sea of Korea. The estimated instantaneous coefficient of total mortality (Z) of blackfin flounder was 1.0542/year, the survival rate (S) was 0.3485, and the instantaneous coefficient of natural mortality (M) was 0.3637/year. From the values of S and M, the instantaneous coefficient of fishing mortality (F) was calculated to be 0.6905/year. The age at first capture was 1.304 years, and the total length was 11.5 cm at that time. On the basis of these parameters, the annual biomass was estimated by a biomass-based cohort analysis using annual catch data in weight by year for 1991-2012 in the East Sea of Korea. The annual biomass peaked in 1997 at about 12,800 mt and then subsequently declined continuously to a level of 10,500 mt in 2004 and to 9,800 mt in 2011 and 2012. The maximum sustainable yield and were estimated as 3,547 mt and 0.3595/year, respectively. Using these estimations, the ABC was estimated to be 3,571 mt in tier 5, 3,397 mt in tier 4, and 2,622 mt in tier 3.

Feeding Habits of the Pacific Cod Gadus macrocephalus in the Coastal Waters off Jumunjin, Gangwondo of Korea

The feeding habits of the Pacific cod Gadus macrocephalus were studied by analyzing the stomach contents of 423 specimens caught by coastal gill net in the coastal waters off Jumunjin, Gangwondo, Korea, from January to December, 2011. The size of Pacific cod ranged from 31.0 to 86.5cm in total length (TL). The proportion of empty stomachs was 25.1%. The main prey items were Macrura, Pisces, and Cephalopoda. In order of abundance, the most dominant species of Macrura, were Pandalus eous, Argis lar, and Neocrangon communis, and the most dominant species of Pisces, were Clupea pallasii, Actoscopus japonicus, and Glyptocephalus stelleri. Berryteuthis magister was the most dominant species of Cephalopoda. In terms of variation in feeding habits by growth, Macrura was the most important prey group for G. macrocephalus ranging in TL from 30- to 55 cm, but Pisces was the most important prey group for cod over 56 cm TL. Catch of G. macrocephalus was significantly positively correlated to catch of the three major Pisces prey species Clupea pallasii, Actoscopus japonicus and Glyptocephalus stelleri.

Crossed Effects of Light and Temperature on the Growth and Maturation of Gametophytes in Costaria costata and Undaria pinnatifida

Faculty of Biological Science and Institute for Basic Science,Wonkwang University, Iksan 54538, Korea 1Institute of Eco and Environmental Incorporation, Bucheon 14501, Korea 2Coastal Water Fisheries Resources Research Division, National Institute of Fisheries Science, Busan 46083, Korea 3Distant Water Fisheries Resources Research Division, National Institute of Fisheries Science, Busan 46083, Korea 4Fisheries Resources and Environment Research Division, National Institute of Fisheries Science, Gangneung 25435, Korea 5Research Cooperation Division, National Institute of Fisheries Science, Busan 46083, Korea