• Korean Journal of Ichthyology
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• v.11 no.2
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• pp.191-197
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• 1999

Stomach contents of hairtail, Trichiurus lepturus collected in the Nakdong River Estuary were examined quantitatively. T. lepturus was a carnivore which consumed mainly fishes, crustaceans (such as copepods, euphausiids and shrimps) and chaetognaths. Its diets included small quantities of small squids. T. lepturus showed ontogenetic progression of three feeding stages : an initial feeding stage was a planktivorous stage in which copepods were the major food item, followed by a mixed feeding stage in which euphausiids, mysids, shrimps, chaetognaths and fishes were the major food items, and finally a piscivorous stage in which fishes were the major food item. Especially anchovies were heavily selected by large T. lepturus.

• Korean Journal of Ichthyology
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• v.12 no.1
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• pp.54-61
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• 2000

Feeding habits of Zoarces gilli collected in the coastal water off Gadeok-do, Korea from March 1998 to February 1999 were studied. Z. gilli was a carnivore and consumed mainly shrimps, gammarid amphipods, fishes, bivalves and cumaceans. Its diets also included small quantities of copepods, caprellid amphipods, ostracods, crabs, squids, gastropods, ophiuroids and polychaetes. It showed ontogenetic changes in feeding habits. Individuals of small size (10~15 cmSL) fed mainly on small prey organisms such as gammarid amphipods, bivalves, cumaceans and ostracods. However, larger shrimps and fishes were heavily selected with increasing fish size.

• Journal of Aquaculture
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• v.20 no.3
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• pp.194-198
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• 2007

Reproductive traits of Palaemon gravieri such as embryo size, number of embryo (fecundity), incubation period, larval development mode, larval development period, larval survival and larval growth were described and compared to analyze the correlation among those traits. Embryo volume is a primary factor determining other ensuing reproductive features. Egg volume was $0.042mm^3$ in the first developmental stage. Embryo volume in P. gravieri was comparatively small which is indicative of great number of embryo (y = 3.0161x + 0.0185 $R^2$ = 0.74 positive isometric relationship) and relatively long incubation period. Larvae survived from zoea 1 to post-larvae and it took 45 days at $22^{\circ}C$. Survival rate of the larvae was rather great in the early stage and thereafter steadily decreased. Daily growth rate of larvae in P. gravieri at $22^{\circ}C$ was 0.0195 mm on average. They grew steadily as time went by. Incubation period was between 10-14 days at $22^{\circ}C$. Larval development mode was almost complete planktotrophic. PNR (point of no return) appeared to be the third day on average. Survival rate of larvae without feeding declined rapidly between 3 and 4 days. Larval development period and stage frequency were 23-30 days and 11 stages which imply prolonged larval period and high mortality. The pattern of brood production followed fast successive parturial pattern. Most ovigerous female had mature ovary when they performed parturial molt soon after hatching (larval release).

• Korean Journal of Ichthyology
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• v.10 no.2
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• pp.176-183
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• 1998

Spawning ecology and feeding habits of Maurolicus muelleri in the Korean waters were studied. M. muelleri spawned continuously throughout the year showing a peak in August. Major spawning ground of this species was the southeastern sea of Korea. The fecundity observed from the ovaries of M. muelleri showed a range of 5,072 to 32,117, and the average number of eggs per one spawning time was approximately 250. M. muelleri was a zooplanktivore which fed mainly on copepods. Its diets also included various crustaceans such as amphipods, euphausiids, shrimps and mysids.

• Journal of Ecology and Environment
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• v.31 no.1
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• pp.9-15
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• 2008

Growth and reproduction of Palaemon serrifer were described and analyzed in a population inhabiting tide pools in warm temperate waters in Korea. The water temperature varied greatly in the tide pools, ranging from 8$^{\circ}C$ to 27.8$^{\circ}C$ Population structure and growth were investigated using size frequency distribution data collected from January to December 2003. Sex ratios fluctuated, but were almost equal during the breeding period. Growth was continuous and size increased gradually throughout the year. Adult females were larger and grew faster than males. von Bertalanffy growth parameters for a one-year sample of females and males were estimated as $L_{i\ddot{A}}$ = 11.32, K = 0.311, $t_0$ = -0.4115 and $L_{i\ddot{A}}$ = 8.36, K = 0.228, $t_0$ = -0.9693 respectively. Breeding was seasonal, starting in May, peaking in August, and finishing by the end of August. The species showed continuous production of successive broods. Laboratory observation showed that females with embryos near hatching had ovaries filled with vitellogenic oocytes ready for spawning. The reproductive output (effort) of each female (mean number of eggs: $552{\sim}1355$) was not high. The mean embryo volume, $0.078mm^3$, is relatively small, indicative of low energy allocation to each embryo. Recruitment of juveniles was closely linked to the breeding period, beginning in September.

• Fisheries and Aquatic Sciences
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• v.13 no.4
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• pp.308-314
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• 2010

Larvae of Palaemon serrifer were reared in the laboratory under three different temperature regimes ($15^{\circ}C$, $20^{\circ}C$, $25^{\circ}C$) to study the effects of rearing temperature on larval survival and growth, as well as other traits such as embryo volume, number of embryos (fecundity), incubation period, development. Mode and development period. Growth pattern was analyzed by measuring the molt increment and intermolt period. The intermolt period consistently increased with size and instar number and was shortest at $25^{\circ}C$. However, molt increments generally decreased with instar number. Number of embryos varied from 552 to 1355. The relationship between the number of embryos and carapace length was expressed by the equation (fecundity) y=2.7744x+0.208 ($R^2$=0.7961). Egg volume was a primary factor affecting other life-history traits. Egg volume was $0.078\;m^3$, which is relatively small thus embryos exhibited a relatively short incubation period and a comparatively short development period, and the nutritional mode was planktotrophic. Brood production was followed by a fast parturitional pattern. Most ovigerous females had mature ovaries when the parturial molt occurred soon after eclosion.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.216-222
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• 2006

Feeding habits of Pagrus major collected in the coastal waters off Busan from January to December 2004 were studied. P. major ranged form 8.5 to 44.6 cm in standard length. P. major was a carnivore which consumed mainly hermit crabs, amphipods, crabs, shrimps, polychaetes, echinoderms, and fishes. Its diets included small quantities of gastropods, bivalves, stomatopods, cephalopods, cnidarians, and isopods. It showed ontogenetic changes in feeding habits. Small individuals (8~15 cm SL) preyed mainly on shrimps. However, individuals from 15 cm to 25 cm SL preyed mainly on hermit crabs and polychaetes. Individuals over 25 cm SL preyed mainly on fishes and echinoderms.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.590-597
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• 2022

We analyzed the diet composition of smallmouth argentine Argentina kagoshimae, which were collected via bottom trawl in the South Sea during February, April, August, and October 2021. Their size range was 8.1-21.4 cm total length. A. kagoshimae are mesopelagic carnivores, mainly consuming benthopelagic Euphausiacea and Caridea crustaceans. Polychaetes were the second largest prey component in their diet, which also included small quantities of copepods, amphipods, and arrow worms. Stomach content compositions substantially differed among body size levels in A. kagoshimae. The results of non-metric multidimensional scaling ordination and permutational multivariate analysis of variance of dietary data revealed no significant dietary differences. The results of a graphical analysis of the diet composition showed that A. kagoshimae are specialized feeders characterized by strong individual feeding specialization.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.583-589
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• 2022

The feeding habits of the marbled flounder Pseudopleuronectes yokohamae were studied using 384 specimens (10.7-52.3 cm in total length) collected from the West Sea, Korea between January and December 2021. P. yokohamae ate mainly polychaeta and gastropoda, incuding teleostei, caridea, euphausiacea, amphipoda and brachyura. The mean number of preys per stomach (mN/ST) showed a statistically significant difference, and the mean weight of prey per stomach (mW/ST) increased as the total length increased. P. yokohamae ate mainly teleostei in spring and winter. P. yokohamae ate mainly euphausiacea in summer and mainly polychaeta in autumn.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.705-713
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• 2022

The feeding habits of Hexagrammos otakii were studied by analyzing the stomach contents of 508 specimens collected from July 2009 to December 2010 off the Yeosu coast of Korea. The total length of the H. otakii specimens ranged from 10.7 to 41.5 cm. H. otakii was found to be a bottom-feeding carnivore that mainly consumed brachyura, amphipoda, but also sonsumed cephalopoda, pisces, anomura, polychaeta, and gastropoda. It was shown through relative importance analysis that the benthic share was 58.1% for brachyura, 24.5% for amphipoda, 7.5% for caridea, and 7.3% for pisces. Brachyura was the main prey item for H. otakii, occupying 35% of the stomach contents. The proportion of brachyura and amphipoda decreased with the growth of H. otakii, and their decrease paralleled the increased consumption of pisces. The shift in feeding habits to larger prey organisms with increasing fish size seems to be one of survival strategies to maximize net energy gain.