• Korean Journal of Ichthyology
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• v.26 no.1
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• pp.42-49
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• 2014

A total of 4 pelagic eggs and 24 larval fish species were collected in Masan Bay. Engraulis japonicus eggs predominated in pelagic eggs. Abundant larval fishes were Omobranchus elegans, Scomber japonicus, Acanthogobius flavimanus, Hexagrammos otakii, Repomucenus sp., Scartella cristata and Gobiidae sp., and these 7 species accounted for 78.5% in the total number of individuals. Temporal and spatial variation in both species composition and abundance of was large: the peak abundances of pelagic eggs and larval fishes occurred in July 2007, whilst these were lowest in February 2007. Higher abundance of ichtyoplankton were at station 5 than those of other stations. Temporal changes in the abundances of pelagic eggs and larval fishes corresponded with temperature. Pelagic eggs and larval fishes varied among stations between with shallower inner stations and deeper outer stations with physical characteristics such as depth and local topography.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.6
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• pp.425-438
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• 1990

Acoustic and ichthyoplankton data collected from Shelikof Strait in 1981, 1984 and 1985 were examined to determine spawning ground and period of walleye pollock, Theragra chalcogramma. Walleye pollock in the Gulf of Alaska migrated into Shelikof Strait for spawning during late winter and early spring. They entered Shelikof Strait via the warm and saline deep layer (continental slope water mass) in the southwestern channel, and major fish schools concentrated for spawning along the deep trough (250~300m) in the western part of the central strait. Peak spawning activity occurred there from late March to early April. Peak spawning time and area in Shelikof Strait varied little between years, despite difference in hydrography. Geographical advantages together with some oceanographic phenomena (reduced water transport and reduced mixed layer depth in spring) made that area an optimal spawning ground in the Gulf of Alaska during early April. After early April, spawning intensity decreased rapidly and the spawning area tended to expand to the northeast and southwest.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.620-632
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• 1994

To study the distribution of ichthyoplankton in Asan Bay, samples were collected with a Bongo net at 8 stations from April, July and October of 1991, and January of 1992. The dominant fish eggs included the eggs of Nibea spp., Engraulis japonica, Callionymus spp., and others. The eggs of Nibea spp. and Engraulis japonica were $97.70\%$ and $1.30\%$ of the total egg abundance, respectively. Twenty three species of fish larvae were identified. The predominant species were gobiid fishes accounting for $32.84\%$ of the all fish larvae, and followed by Ammodytes personatus($16.69\%$). Other major species were Anguilla japonica, Nibea spp., Pampus echinogaster and Engrualis japonica. These 6 taxa constituted $90.40\%$ of the total larvae collected.

• Korean Journal of Ichthyology
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• v.31 no.3
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• pp.159-164
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• 2019

Species composition and seasonal variation of fish eggs and larvae were investigated from 2017 to 2018. During the study period, the fish eggs were identified as belonging to 6 taxa. The dominant species of fish eggs were Engraulis japonicus, Leiognathus nuchalis, and Konosirus punctatus. These three species accounted for 96% of the total number of individuals collected. The collected larval fishes were identified into 17 taxa, 11 families, and 5 orders. The dominant species of larval fish were Engraulis japonicus, Leiognathus nuchalis, and Konosirus punctatus. These three species accounted for 70% of the total number of individuals collected. The diversity index of the larval fishes was the highest in summer (H'=1.78) and the lowest in winter (H'=1.34). The economically important species in this area were Engraulis japonicus, Konosirus punctatus, Sebastes schlegelii, Cynoglossus joyneri and Stephanolepis cirrhifer.

• 한국해양학회지
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• v.25 no.3
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• pp.131-134
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• 1990

Estimates of larval mortality for many marine fishes are based on field collections from several consecutive ichthyoplankton surveys, assuming that the surveys have covered the entire areas of larval habitats. The oceanic environment, however, is so dynamic and complicated that planktonic forms cannot stay within a confined area for a prolonged period. This note is prepared as a more detailed explanation of the estimates of fish larval mortality in the oceanic dispersing system, as a supplement of Kim and Bang (1990).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.907-916
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• 2013

The aim of this study was to compare community structure of larval fish species in the northern East China Sea during normal meteorological conditions in autumn 2009, during the El Ni$\tilde{n}$o period in 2009-2010, and during the La Nina period in 2010. Fifty taxa were recorded during the study period; the most dominant species were Benthosema pterotum and Gobiidae spp. In October 2008 during the normal period, warm water from the Tsushima Warm Current (TWC) intruded more into the surface and middle layers, and cold water affected by the Yellow Sea Cold Water (YSCW) intruded into the bottom layer. In October 2009 during the El Ni$\tilde{n}$o period, intrusion of the China Coastal Water (CCW), which has low salinity (<32.2 psu), was more apparent than intrusion of the TWC or YSCW. In October 2010 during the La Nina period, intrusion of the TWC and CCW was relatively weak, resulting in the lowest temperature and highest salinity observed during the study period in the eastern part of the study area. Hierarchical cluster, one-way ANOSIM (analysis of similarities), and SIMPER (similarity-percentages procedure) analyses provided two main results. First, the abundance of the most dominant larval fish species in autumn of the normal period was greater than that in autumn of the El Ni$\tilde{n}$o/La Nina periods, resulting in a significant difference in ichthyoplankton community structure between the periods. The abundance of Benthosema pterotum increased in the normal period, possibly influenced by the intrusion of cold water from the YSCW; the abundance of species residing in Korean waters (e.g., Gobiidae spp.) probably decreased during the El Ni$\tilde{n}$o/La Nina periods. The second finding was that the abundance of subtropical larval fish in autumn of the normal period was generally larger than that during autumn of the El Ni$\tilde{n}$o/La Nina periods. This could have been induced by the stronger intrusion of warm water from the TWC during the normal period. Although differences in oceanographic conditions between El Ni$\tilde{n}$o and La Nina periods were observed, the differences in ichthyoplankton community structure between the two periods were not significant.

• Fisheries and Aquatic Sciences
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• v.14 no.1
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• pp.55-61
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• 2011

Fish larvae were collected monthly with an ichthyoplankton net from 18 stations (including four stations located in eelgrass beds) in Gamak Bay and Yeoja Bay, southern Korea, in 2007. In total, 33 species of fish larvae were collected, of which Engraulis japonicus (48.5%), Tridentiger trigonocephalus (21.5%), and Omobranchus elegans (9.2%) were dominant. Dominant species varied seasonally: Hexagrammos otakii during December and January, Pholis nebulosa during January and March, Acanthogobius flavimanus in April, T. trigonocephalus in May, E. japonicus during June, July, September, and November, and Sillago japonica in August. Dominant species also differed between sites inside and outside the bays. Leiognathus nuchalis, O. elegans, and T. trigonocephalus were more abundant inside, while H. otakii was more abundant outside. From cluster analysis, three groups were identified according to sampling months (January-April, May-September, and October-December) and two groups according to station (inside and outside bays). The occurrence of small larvae of almost all major fish species indicated that the bays were used as spawning and nursery grounds. An exception was Lateolabrax japonicus, whose specimens were relatively large (>19 mm TL), suggesting that this fish may spawn offshore, with its juveniles approaching the bays with growth.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.495-500
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• 1992

The relationship between distribution of eggs and larvae of anchovy, Engraulis japonica, and environmental factors were studied using the data on the ichthyoplankton and zooplankton sampled vertically by net, and water temperature and salinity observed by CTB in the eastern waters of Korea in every two month in 1985. Anchovy eggs and larvae were occurred in June and August. They distributed in the warm water current which was high temperature and salinity in June. Egg and larval distribution area were moved to the offshore in August. It is likely that distribution of anchovy eggs and larval in June significantly correlate with hydroconditions in the eastern waters of Korea.

• Korean Journal of Ichthyology
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• v.3 no.1
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• pp.11-23
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• 1991

To study the distribution of inhthyoplankton in the adjacent water of Wolsong, samples were collected using Bongo net from the surface water in November of 1989, and February, May and July of 1990. Fish eggs were divided into Engrualis japonicus, Callionymidae, Maurolicus muelleri, Konosirus punctatus, and others. The dominant species of fish eggs were Maurolicus muelleri and Callionymidae accounting for 60.1% and 13.7% of the total egg abundance, respectively. Total of 21 taxa of fish larvae occurred. The predominant species was Engraulis japonicas accounting for 61.2% of the total lavae, and bollowed by Callionymidae(11.9%). Other major species were Maurolicus muelleri, Gobiidae sp., Ammodytes personatus, Sebastes inermis, S. Pachycephalus, Scartella cristata, and Sebastiscus marmoratus. These 9 taxa constituted 96.5% of the total larvae collected. In this area, where upwelling occasionally occurs the distribution of fish eggs and larvae appeared to be affected by the transport of the surface water during the upwelling period.

• Korean Journal of Ichthyology
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• v.5 no.2
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• pp.217-225
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• 1993

A study on the distribution and mortality of eggs and larvae of anchovy. Engraulis japonica, was carried out on the basis of data collected from ichthyoplankton survey in the southern coastal waters of Korea from June to August in 1990. Egg and larval distribution areas were shifted from the adjacent waters of Namhae Is, to the eastern waters of Goeje Is, while eggs and larvae were developed in June. However, high densities of eggs and larvae of anchovy and were found near Goeje Is. in July. Anchovy eggs and larvae were correlated significantly with zooplankton in July, and were not in June and August. It is likely that the low instantaneous mortality coefficients in eggs and high values in the larvae during June and high values in eggs and low values in the larvae during July were affected by the distribution pattern of zooplankton.