• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.5
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• pp.667-675
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• 2023

The Spanish mackerel Scomberomorus niphonius is an economically important fish species in the southwestern waters of Korea. This study aimed to provide insights into the reproductive biology of this species in the southwestern waters of Korea. We analyzed monthly changes in fork length (FL), maturity stages, and gonadosomatic index (GSI). Moreover, we measured the in FL at sexual group maturity of 50%, 75%, 97.5%, and sex ratio (female vs. male). The overall sex ratio of female and male was 1:0.8. GSI value showed the highest peak in May; however, the spawning period revealed by the microscopic analysis of gonad tissue of S. niphonius was from April to August 2020. The main spawning seasons for the entire populations was from May to June. The fork length at 50% group maturity was 53.3 cm for females and 53.1 cm for males. These results of spawning period of Spanish mackerel highlight the influences of water temperatures that were higher than those in the past, an increase in resource levels, and the level of Pacific anchovy resources flowing into the spawning ground.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.3
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• pp.376-384
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• 2016

Seasonal catch distributions of large purse seines and daily landings of coastal set nets were analyzed to understand the migration path of the Spanish mackerel Scomberomorus niphonius around Korean waters. The Spanish mackerel start to move toward the coastal region in the South and West Sea in May for spawning and stay until July, when spawning finishes. Afterwards, they start to migrate to the East China Sea and the southern East Sea and are found irrespective of the onshore and offshore regions. Therefore, they disappear from the offshore region during the spawning season in June and July, and a new recruitment population of age 0 begins to inflow into the coastal fishing grounds in the South Sea and West Sea in August, one month earlier than in the Japanese coastal region of the East Sea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.4
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• pp.248-253
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• 2007

We studied the maturation and spawning of female Spanish mackerel (Scomberomorus niphonius) based on 445 specimens collected monthly from January to December 2004 in the coastal waters off Busan. The fork length (FL) of S. niphonius ranged from 26.1 to 105.4 cm, the gonadosomatic index (GSI) of the females was highest in May 2004, and the spawning season take place from April to July. A significant difference was detected in the sex ratio between females and males ($X^2$ test, p<0.01). The percentage of sexually mature females exceeded 50% in the 50-60 cm (FL) size group and reached 100% in the over 70 cm (FL) size group. Fecundity (F) varied between 201,156 and 836,426 egg per female. The relationship between F and FL of the fish was expressed as $F=5.8756FL^{3.8465}$. The relationship F and body weight (BW) was expressed as F=581.421 n (BW)-4108.5. The first spawning length was 41.8 cm (FL.)

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.2
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• pp.125-131
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• 1996

In order to investigate the relation between the environmental properties and the catch fluctuation of set net fishing grounds located in the coastal waters of Yosu, oceanographic observations on the fishing grounds were carried out by the training ship ofYosu Fisheries University from January, 1990 to September, 1992, and the data obtained were compared with the catch data from the joint market ofYosu fisheries cooperative society from 1984 to 1993. The resuItes obtained are summerized as follows : 1. The ranges of water temperature and salinity in the fishing ground was 7.0 to $27^{\circ}C.$and 26.6 to 33.2${\textperthousand}$, and water temperature increased from March to August and decreased from September to February of following year. 2. The salinity in the fishing grounds was relatively high without significant changes from November to June of the following year. From July, however, the salinity decreased to continue a low value till September and then increased. The salinity in the fishing ground was dominated mainly by the precipitation and its variation was large at the north entrance of set net fishing ground, influenced greatly by the land waters from the river of Somjin, but small in the offshore of the fishing grounds. 3. The fishes caught by the set nets were arranged in order of catch as follows; Spanish mackerel> Horse mackerel > Sardine > Anchovy > Hair tail. The catches of Anchovy and Sardine were high in April to May and those of Hair tail in June to July, but Spanish mackerel and Horse mackerel were caught for whole period of fishing. Spanish mackerel was caught most in September and least in April and their means were largest in August and smallest in June. 4. The ranges of optimum water temperature for fishing by the set nets was 13.5 to $25^{\circ}C.$, and in the ranges the catches increased with increasing temperature. The ranges of optimum salinity for fishing varied between 25.0 and 32.0${\textperthousand}$.

• 한국해양학회지
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• v.5 no.1
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• pp.37-40
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• 1970

This work concerns age studies of the spanish mackerel by vertebrae. The spanish mackerel samples were obtained mainly from Yosoo and Inchon regions during July to December, 1969. A total of 292 fish was collected during the present study. Except the vertebrae, the incremental growth is found to be vague or complicated on the most bony parts in spanish mackerel. The spanish mackerel has 50 vertebrae, and the size of vertebra varies according to its position. After several studies, therefore, sample centrum was selected from the 23rd vertebra throughout the present study. Sample centrum was then stained with Alizarin Red S. and examined under binocular stereoscopic microscope illuminated by reflected light. The surface of the centrum shows many ring-marks running parallel to the edge. The ring-marks were counted and the measurements of centrum radius (R) and radii of the ring-marks (r$\_$i/) were made by eyepiece micrometer. From available data, the average of each ring-mark radius was found to be; r$\_$1/=2.05mm, r$\_$2/=3.11mm, r$\_$3/=4.05mm, r$\_$4/=4.89mm, r$\_$5/=5.70mm and r$\_$6/=6.47mm, respectively. The mean fork length at the time of ring-mark formation was calculated to be; l$\_$1/=297.6mm, l$\_$2/= 390.1mm, l$\_$3/=472.2mm, l$\_$4/=545.5mm, l$\_$5/=616.2mm, and l$\_$6/= 683.4mm, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.2
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• pp.107-117
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• 2012

Korean large purse seine fishery catches chub mackerel, sardine, jack mackerel, Spanish mackerel, etc. which are mainly pelagic fish species. The proportion of chub mackerel was 60% over in Korean large purse seine fishery. Sea surface temperature (SST) increased $0.0253^{\circ}C$ per year and total rising rate was $0.759^{\circ}C$ from 1980 to 2009 in the southern sea of Korea, where is mainly fishing grounds of Korean large purse seine. It was that p<0.01 level was statistically significant. It is northward movement that the center of fishing grounds of chub mackerel by Korean large purse seine fishery moved 4.57km/yr. It was rapidly northward movement about 7.1km/yr, 8.13km/yr to move Spanish mackerel and bluefin tuna fishing grounds. However, the fishing grounds of jack mackerel were moved further south in the 2000s than the 1980s. Catch of tunas and bluefin tuna consistently increased in Korean waters. There was a significantly positive correlation between SST and catch of bluefin tuna in the fishing grounds of Korean waters.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.122-129
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• 1981

Histamine has been known to be one of the causative materials of allergy-like food poisoning from eating of the meat of the dark-fleshed fishes. In the previous study, we had reported the changes of histamine contents fin three kinds of the dark-fleshed fishes. The present paper was also conducted to investigate the changes of the histamine contents in the mackerel pike, and compare with the white-fleshed fish, spanish mackerel, under different condition of storage and processing. The formation of histamine in the muscle of mackerel pike was markedly higher than spanish mackerel. Referring to temperature, the formation of histamine at $12^{\circ}C$ was observed more rapid than that at $2^{\circ}C$. In the muscle of mackerel pike, the histamine contents reached the levels of 98.3mg/100g for at the storage for 5 days at $12^{\circ}C$. But in that of spanish mackerel, the content showed the level of 4.9mg/100g at the storage 7 days at $12^{\circ}C$. The histamine contents in sun dried products of the samples were higher than those of rat-materials, salted or hot-air dried products.

• Journal of the korean veterinary medical association
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• v.52 no.10
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• pp.616-620
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• 2016

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.29 no.2
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• pp.94-108
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• 1993

In order to investigate the relation between the environmental properties and catch fluctuation of set net fishing ground located in the coastal waters of Yeosu, oceanographic observation and catches on the grounds were carried out from Jan. to Dec. in 1990 and 1992. The results obtained are summarized as follows; 1) Because of the surveyed area is a costal shallow water, the fishing ground was influenced largely by atmospheric phenomena such as air temperature. precipitation. etc. and so showed large variations in temperature and salinity yearly. The inner water flowed out mainly between Yeosu ad Namhe-do, and then through Kumo-do between Dolsan-do and Kumo-do. On the other hand, off shore water was supplied into the fishing ground from the vicinity of Sori-do and Yokchi-do. thus the fishing ground was occupied usually by various sources of water. 2) The water mass in the fishing ground were divided into the inner water(29.0～30.6$\textperthousand$) and the mixed water(31,7～32.2$\textperthousand$) and off shore water(32.3～32.8$\textperthousand$) accourding to the distribution of salinity from T-S diagram plotted all salinity data observed in 1990 and 1992. In summer the inner and mixing water which was formed by river flowed southerly and spread south-easterly in the vicinity of Kumo-do. The off shore water which supplied from the vicinity of Sori-do and Yokchi-do and inner water formed the thermal front and halo front in summer. 3) The fishes caught by the set net were arranged in the order of catch amounts as follows: Spanish mackerel>Horse mackerel >Hair tail>Common mackerel> Sardine> Anchovy. The Catches of anchovy and sardine were high in April to May and those of hair tail and horse mackerel in July to September, but spanish mackerel were caught during the whole period of fishing. When inner water and mixing water appeared respectively and inner water and mixing water speared together in the set net fishing ground, the set net showed a high catch.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.4
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• pp.317-327
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• 2012

The changes in the proximate compositions, lipid classes, and fatty acids of muscle and dripped lipids, and the amino acid compositions and mineral content were studied in Spanish mackerel Scomberomorus niphonius muscle cooked using a frying pan, oven, and microwave oven. The moisture content was high in the raw sample (65.7%) and decreased with cooking, decreasing the most with frying pan method (54.5%). Conversely, the protein, lipid and ash contents increased significantly with cooking (P<0.05). The dripped lipid content from the cooked muscles was the highest with the frying pan sample (0.81%) and was approximately half this level in the oven (0.46%) and microwave oven (0.34%) samples. The percentage of non-polar lipid (NL) in the total lipid content exceeded 95% for the muscle lipids (13.9-17.6 g/100 g sample) and 99% for the dripped lipids (0.34-0.81 g/100 g sample). The prominent fatty acids were 18:1n-9, 16:0, 22:6n-3, 16:1n-7, and 20:5n-3 in the muscle and dripped lipids. The frying pan muscle lipid contained high levels of saturates and monoenes such as 16:0, 18:0, and 18:1n-9, and low levels of polyenes compared with other muscle lipids. The fatty acid compositions of the dripped lipids were similar with all three cooking methods. The prominent total amino acids in Spanish mackerel muscle were glutamic acid, aspartic acid, lysine, leucine, and arginine, and their proportions were similar (45.49-45.82%) in all samples. The potassium and phosphorous contents increased significantly with cooking (P<0.05), and while no heavy metals were detected in any sample. These results indicate that the change in nutritional components, especially the lipid content, was lower with the microwave oven and oven methods compared with the frying pan method.