• 수산해양기술연구
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• 제49권4호
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• pp.360-367
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• 2013

The mesh selectivity of the gillnet for Pacific herring (Clupea pallasii) was examined in field experiments with four different mesh sizes (63, 69, 75 and 81mm) from June to July, 2013 in the coastal areas of Imwon in Gangwon province. The fishing performance tests were conducted with a commercial Pacific herring gillnet and a biodegradable gillnet for Pacific herring together selectivity tests. The filed tests were carried out the total 11 times. The master curve of selectivity was estimated by the extended Kitahara's method. In the results, the catch number of Pacific herring was 9,409 (2,203kg) and occupied 84.2% in total catches weight. The optimal mesh size for 50% retention on first maturity size (female, 250mm) of Pacific herring was estimated as 64.5mm by master selectivity curves. The fishing performance of the biodegradable gillnet was showed to be equivalent with commercial gill for Pacific herring.

• 한국수산과학회지
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• 제54권2호
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• pp.208-217
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• 2021

This study described the fishing characteristics of Pacific herring Clupea pallasii and examined the relationship between its catch and sea temperature in Korean waters from 1970 to 2019. Although the herring catch in Korean waters stayed below 1,000 tons per year from the mid-1970s to mid-1980s, the catch in the winters in the East Sea of Korea started to increase markedly after 1987-1988, when the sea surface temperature (SST) seemed to shift to a warmer regime. Since the mid-2000s, overall, herring was caught throughout the year in the East Sea and eastern South Sea of Korea, and its catch significantly increased by around 30,000 tons per year. The main fishing grounds of herring in the poor fishing years until the mid-1980s were possibly formed in the western offshore of Korea, and subsequently the fishing grounds were distributed in the eastern coast of Korea. While the standardized catch per unit effort (CPUE) for two main fisheries of herring catch was significantly correlated with the herring catch since the 2000s, there was a gradual decline since the 2010s. The herring catch in the East Sea had significant positive correlations with SSTs, but that in the West Sea had a significant negative correlation.

• 한국수산과학회지
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• 제48권5호
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• pp.604-613
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• 2015

The objective of this study was to estimate the food quality of commercial boiled-dried Pacific herring Clupea pallasi as a substitute for boiled-dried anchovy. Standards for controlling quality of boiled-dried Pacific herring were suggested based on international (US FDA and CODEX) and domestic (Korean FDA, Standards on Quality of Seafood and Seafood Products, KS) standards for boiled-dried anchovy. The standards included requirements for moisture [less than 30% (less than 35 in very tiny sizes)], water activity (less than 0.85), salinity (less than 10%), water-phase salt (less than 20%), acid-insoluble ash (less than 1.5%), yeast and mold (fewer than 1.0×10³ CFU/g), and different size and breakage (less than 5%). Based on the standards suggested, commercial boiled-dried Pacific herring passed nine levels (all levels) in water activity, acid-insoluble ash, mold and yeast concentrations; seven levels (L-1, 2, 3, 4, M-1, 2, S) in water-phase salt, and three levels (L-1, 3, 4) in the ratio of different size and breakage categories. These results suggest that the quality of commercial boiled-dried Pacific herring is similar to that of commercial boiled-dried anchovy.

• 수산해양기술연구
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• 제51권3호
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• pp.370-374
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• 2015

Pacific herring Clupea pallasii eggs were attached to the gill net in Korean coastal waters off Busan. To conservation and management the eggs attached to the gill net, we followed the natural hatching in coastal waters from five days after fertilization to the hatching finished, where the temperature was $9^{\circ}C$. The diameter of fertilized eggs was 1.24-1.55 mm (n= 50), and had a segmented pale yellow yolk, no oil globule. Natural hatching had started by 10 days after fertilization. Mass hatching occurred around 11-12 days after fertilization, most of eggs separated from the gill net. Therefore, when the Pacific herring eggs attached in gill net, should be natural hatching-induced in coastal waters during 12-14 days.

• 한국수산과학회지
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• 제55권2호
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• pp.224-228
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• 2022

The feeding habits of the Pacific herring Clupea pallasii were examined based on 333 specimens collected from the coastal waters of the East Sea of Korea. Sampling was conducted in April, June, and September 2019 and February 2020. The total length of the C. pallasii ranged from 11.9 cm to 37.7 cm. Euphausiids (93.0%, index of relative importance, IRI), especially Euphausia, comprised the primary diet of the pacific herring, in addition to amphipods, copepods, and fishes. The dietary composition of C. pallasii showed non-significant differences by size. As body size of C. pallasii increased, the mean number of preys per stomach (mN/ST) and the mean weight of preys per stomach (mW/ST) tended to increase.

• 수산해양기술연구
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• 제53권4호
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• pp.396-403
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• 2017

We measured the target strength according to the swimming tilt angle and size change for Pacific herring at the frequency of 70 kHz as the basic database in order to estimate its abundance as well as density in the survey area using the hydroacoustical method. The number of the sample used in this study was 14 individuals, and its size distribution by fork length ranged between 20.3 and 29.8 cm and wet weight was measured between 187.6 and 269.9 g. The variation of TS according to the swimming angle ($-30{\sim}30^{\circ}$) was measured between 10.3 and 18.8 dB in frequency range, the highest value was measured at head-down of Pacific herring in the tilt angle range between 5 and 9 deg. of its swimbladder. The relationship between TS-FL of herring was the same as $TS=20log_{10}$ (FL) - 66.79 when its swimming tilt angle in the daytime ($3.8{\pm}6.0^{\circ}$) and nighttime ($-3.2{\pm}13.6^{\circ}$), respectively.

• 한국수산학회:학술대회논문집
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• 한국수산학회 2005년도 춘계학술대회
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• pp.21-23
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• 2005

• 한국수산과학회지
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• 제48권5호
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• pp.614-620
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• 2015

The objective of this study was to investigate sensory and lipid characterizations of boiled-dried Pacific herring Clupea pallasii (PH) as a substitute for boiled-dried anchovies (A). The crude lipid content of commercial boiled-dried PH ranged from 1.3 to 5.1%, which was similar to that of commercial boiled-dried A (2.2-5.1%). The peroxide values (POVs) of commercial boiled-dried PH ranged from 20.5 to 129.1 meq/kg. The POVs of commercial boiled-dried PH suggest that boiled-dried PA of high quality should be controlled by a POV standard similar to that of boiled-dried A. The trichloroacetic acid soluble-nitrogen (TCA soluble-N) content of commercial boiled-dried PH ranged from 495.7 to 998.6 mg/100 g, which was high compared to that of commercial boiled-dried A (372.6-690.0 mg/100 g). Volatile basic nitrogen (VBN) content of commercial boiled-dried PH ranged from 8.4 to 28.1 mg/100 g, which was low compared to that of commercial boiled-dried A (16.8-33.0 mg/100 g). Results from the lipid, POV, TCA-soluble-N, and VBN content analyses suggest that boiled-dried PH could be used as a substitute for boiled-dried A.

• 한국어류학회지
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• 제29권4호
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• pp.267-271
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• 2017

본 연구는 여름철 동해 남부 연안에 출현하는 청어 유어 301개체의 일섭식율 변동을 조사하였다. 어류 시료는 여름철에 3시간 간격으로 24시간 동안 소형 저인망을 이용하여 채집하였다. 청어 유어의 공위율(ratio of empty stomach), 만복도(stomach fullness), 위내용물중량지수(stomach contents index, SCI), 만복도지수(stomach fullness index, IF)는 낮과 밤의 변화에 따라 뚜렷하게 변동하였다. 공위율은 밤에 높았지만, 다른 지수들은 낮에 높아지는 경향을 보였고, 일몰 직전에 가장 높은 값을 보였다. 낮 동안 청어 유어의 위내용물은 요각류(Copepoda)와 난바다곤쟁이류(Euphausiacea)로 구성되어 있었고, 자정 근처에는 거의 소화되어 확인이 어려운 먹이생물로 구성되어 있었다.

• 수산해양기술연구
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• 제51권3호
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• pp.348-354
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• 2015

Experiments for catch and cluster analysis on the catch by gillnet for the Pacific herring were conducted using traditional nylon net (PA) and developing biodegradable net (PBS) with different monofilaments of #2 (=0.23 mm) and #3 (=0.28 mm) in diameter between 2011 and 2012, and of #2, #2.5 and #3 in 2013 in the eastern coastal waters of Samcheok, Korea. The total catch during the experiments was 3,337kg in weight and 16,757 individuals in number. Though the catch ratio of the Pacific herring in 2011 and 2012 was 97.4% and 98.7%, respectively, that of the Pacific herring in 2013 was 73.6% as the biggest and followed by goldeye rockfish (8.6%), black edged sculpin (8.4%), atka mackerel (7.2%) and Alaska cod (1.0%). The ANOVA analysis on the total catch in relation to net material showed that there was not statistically significant difference at the 5% level between nylon net (PA) and biodegradable net (PBS) (p=0.91). With the cluster analysis on the catch in relation to net material (PA, PBS) and twine thick (#2, #3), it showed the influence of net material on the catch was greater than that of twine diameter in this experiment. From the test of homogeneity on the catch by the gillnet with PA and PBS in which several species were caught in 2013, there was not statistically significant homogeneity in relation to net material (p<0.005). That meant the traditional gillnet of nylon (PA) was more efficient than the biodegradable (PBS) gillnet to catch several kinds of fish, however the PBS gillnet was better than the PA gillnet to catch the target Pacific herring.