• Korean Journal of Ichthyology
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• v.26 no.4
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• pp.349-354
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• 2014

The diet composition of bullet mackerel, Auxis rochei was studied using 200 specimens collected from December 2013 to May 2014 in the coastal waters of Iloilo, Philippines. The size of A. rochei ranged from 11.1 to 31.2 cm in fork length (FL). A. rochei was epipelagic feeder that consumed mainly fishes. In addition, A. rochei consumed shrimps, copepods, crab larvae, amphipods and cephalopods. The diet also included small quantities of stomatopods, bivalves, and ostracods. Also, analysis of the prey-specific abundance against the frequency of occurrence shows that A. rochei have a narrow food niche, and are specialized feeder with fish as their dominant prey. Although fishes were the primary in food consumed by all size class. The fishes gradually increased with body size.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.1
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• pp.6-12
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• 1998

The moving behaviour of Yellowtail Seriola quinqueradiata schools in the main-net of a large scale set-net was investigated in relation to the catching function of the funnel-net by a scanning sonar. The investigation was took place in the Kishihata set-net fishing ground located in Nanao city Ishigawa prefecture, Japan from Nov. 9 to Nov. 13, 1992. The obtained results are summarized as follows; 1. Fish schools showed the greatest number at the playground in the morning and at the bag-net in the afternoon. The fish schools remained long time in the main-net. 2. The rate of fish school through the funnel-net was smaller than that of fish school which is though the playground and bag-net. Because the Yellowtail school changed the shape of school in passing the funnel-net. 3. The rate of entering the bag-net was 24%, among the fish school heading to the outer funnel-net. But, the rate of escaping to the playground was 27%, among the fish school heading to the inner funnel-net. It seems that the structure of the outer funnel-net was not enough to lead the fish to the bag-net. However, the structure of the inner funnel-net was very effective at preventing escape. 4. It is appropriate to haul the net in the morning in considering the number of accumulated fish in the bag-net during the survey.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.295-302
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• 1999

To study the distribution of ichthyoplankton in the adjacent waters of Yousu, ichthyoplankton were sampled 4 times (September 1996, November 1996, February 1997 and May 1997). Four species of fish eggs and twenty-four species of fish larvae were identified. Among fish eggs, Engraulis japonicus eggs were the dominant species comprising $80.6\%$ of the total fish eggs collected, followed by Callionymidae spp. $1.6\%$, Konosirus punctatus and Maurolicus muelleri occupied below $1.0\%$ respectively, while $17.8\%$ were unidentified. Most larval fish species were found in September (17 species). In fish larvae, Callionymidae spp. was the dominant species occupying $25.7\%$ of total fish larvae collected and than followed by Gobiidae spp. $23.5\%$, Sillago japonica $17.2\%$ Engraulis japonicus $12.2\%$, Omobranchus elegans $9.9\%$ and the unidentified species were less than $2.0\%$. The larvae fish species collected in this study area were comprising the coastal sedentary species (Gobiidae, Callionymidae, Hexagrammos otakii and io on), and the warm water species (Auxis spp. and Coryphaena hipurus and Pomacentridae spp.) which were appearing by warm water current flowing near the costal area of Cheju Island.