• 한국발생생물학회지:발생과생식
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• 제20권2호
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• pp.119-125
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• 2016

This study describes results on sexual maturation and characteristics of natural spawned eggs to develop a method for the production of stable, healthy fertilized eggs from captive-reared yellowtail kingfish, Seriola lalandi. A total of 59 yellowtail kingfish were captured off the coast of Jeju Island, after which the broodstock was cultured in indoor culture tank ($100m^3$) until they were 6.1-14.9 kg in body weight. As part of the rearing management for induced sex maturation, the intensity of illumination was maintained at 130 lux. The photoperiod (light/dark; L/D) was set to a 12 L/12 D from October 2013 to January 2014, and 15 L/9 D from February 2014 to June 2014. Feeds comprised mainly EP (Extruded Pellets), with squid cuttlefish added for improvement of egg quality, and was given from April to June 2014. The first spawning of yellowtail kingfish occurred in May 3, 2014, at a water temperature of $17.0^{\circ}C$. Spawning continued until June 12, 2014, with the water temperature set at $20.5^{\circ}C$. Time of spawning was 26 times at this period. The total number of eggs that spawned during the spawning period was $4,449{\times}10^3$. The buoyant rate of spawning eggs and fertilization rate of buoyant eggs during the spawned period were 76.1% and 100%, respectively. The diameters of the egg and oil globule were $1.388{\pm}0.041mm$ and $0.378{\pm}0.029mm$, respectively, which was higher in early eggs than in those from late during the spawned period.

• 한국발생생물학회지:발생과생식
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• 제20권2호
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• pp.109-118
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• 2016

This study monitored the morphological development of embryo, larvae and juvenile yellowtail kingfish, Seriola lalandi, for their aquaculture. The fertilized eggs obtained by natural spawning were spherical shape and buoyant. Fertilized eggs were transparent and had one oil globule in the yolk, with an egg diameter of $1.35{\pm}0.04mm$ and an oil globule diameter of $0.32{\pm}0.02mm$. The fertilized eggs hatched 67-75 h after fertilization in water at $20{\pm}0.5^{\circ}C$. The total length (TL) of the hatched larvae was $3.62{\pm}0.16mm$. During hatching, the larvae, with their mouth and anus not yet opened. The yolk was completely absorbed 3 days after hatching (DAH), while the TL of post-larvae was $4.72{\pm}0.07mm$. At 40 DAH, the juveniles had grown to $30.44{\pm}4.07mm$ in TL, body depth increased, the body color changed to a black, yellow, and light gray-blue color, and 3-4 vertical stripes appeared. At 45 DAH, the juveniles were $38.67{\pm}5.65mm$ in TL and $10.10{\pm}0.94mm$ in body depth. The fish were green with a light orange color, with 7 faint green-brown stripes on the sides of their body. At 87 DAH, the juveniles had grown to 236.11 mm in TL, 217.68 mm in fork length, and 136.5 g in weight. The fish resembled their adult form, with a light yellow-green body color, loss of the pattern on the sides of their body, and a yellow coloration at the tip of the caudal fin.

• 한국수산과학회지
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• 제37권1호
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• pp.65-72
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• 2004

Fish catch by a set net in Hamdeuk fishing ground off Jeju Island were studied to determine seasonal variation of species composition and catch from 1998 to 2000. A total 72,022.9 kg was caught during the survey period, including Scomber japonicus and Trachurus japonicus of $76.4\%$ in the total. The other dominant species were Siganus fuscescens, Loligo chinesis, Seriola dumerili, Sepioteuthis lessoniana, Sardinops melanostictus, and Seriola lalandi accounting to $20.0\%$ of the total. The fishing period conducted by a set net in Hamdeuk fishing ground were from May to November. The catch by a set net were higher in summer than in spring and autumn and closely related with the seasonal variation of sea water temperature. The catch was higher in 1998 than In 1999 and 2000, which was related to the sea water temperature in fishing ground.

• 한국어류학회지
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• 제20권1호
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• pp.28-35
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• 2008

제주도 귀덕 정치망 어장의 유영생물 조성과 변동양상을 알아보기 위하여 2004년 4월부터 12월까지 어업이 행해지는 동안 매일 조사한 결과를 요약하면 다음과 같다. 1. 조사기간 동안 총어종수 21종과 총어획량 45,473.2 kg의 유영생물이 어획되었으며, 이중 어류가 17종 34,285.4 kg, 두족류가 4종 11,187.8 kg이었다. 2. 어획된 유영생물 중에는 전갱이와 독가시치가 가장 많은 비율로 전체 어획량의 44.3%를 차지하였으며, 그 외 흰오징어, 잿방어, 방어, 화살오징어, 부시리 등이 54.4%이었다. 3. 주 우점어종인 전갱이와 독가시치는 어기동안 대부분 어획되었으나, 이중 전갱이는 수온이 높은 여름철과 가을철에 많이 어획된 반면, 독가시치는 여름철에 많이 어획되었다. 4. 귀덕 정치망의 어획량은 봄철에서 여름철로 갈수록 증가하는 경향이었으나 일 변동 폭은 크게 나타났으며, 특히 여름철 전후의 많은 어획량은 우점종인 전갱이와 독가시치, 잿방어, 화살오징어, 흰오징어 등의 어장가입과 관련 있었다. 5. 또한, 어기가 시작되는 봄철에는 방어와 흰오징어가 우점하였다.

• 한국어류학회지
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• 제13권3호
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• pp.210-219
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• 2001

제주 연안 4개 지역 정치망어획량 조사결과, 총 어획량은 153,862 kg으로 이중 전갱이가 89,530 kg으로 전체의 58.2%를 차지하였고, 그 다음으로 독가시치 (9.0%), 살오징어 (5.8%), 한치오징어 (2.9%), 부시리 (1.9%), 흰오징어 (1.8%), 방어 (1.6%) 등이 차지하고 있었다. 가장 많이 어획된 전갱이는 제주도 북쪽 구엄해역에서 88,710 kg이 어획되어 전갱이 전체어획량의 97%를 차지하였다. 이번 4개 해역 조사 결과, 제주연안의 어기는 보통 4월에 시작하여 12월까지 진행되나, 어획량은 봄에서 여름철로 갈수록 높아지고, 가을 및 겨울철로 갈수록 어획량은 낮아지는 현상을 나타내었다. 이와 같은 현상은 수온변화와 관련이 있었다. 정치망 어장별 수온범위는 평대가 $18{\sim}26^{\circ}C$, 두모가 $16{\sim}26^{\circ}C$, 구엄이 $15{\sim}26^{\circ}C$, 강정이 $15{\sim}26^{\circ}C$이었으나, 어획량은 각 어장별 수온범위내에서 수온이 증가할 수록 증가하는 경향에 있었다.