• Animal Systematics, Evolution and Diversity
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• v.36 no.4
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• pp.382-386
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• 2020

In this study, Prionospio depauperata Imajima, 1990 is newly reported in Korean fauna. Prionospio depauperata can be distinguished from other relatives by the four pairs of branchiae which are pinnate on chaetigers 2 and 5, and apinnate on chaetigers 3 and 4; caruncle extending to the end of chaetiger 2; and moderate dorsal crest present on chaetigers 7-13. The morphological diagnosis of P. depauperata are provided with the photographs of four Prionospio species. The mitochondrial cytochrome c oxidase subunit 1 (CO1), 16S ribosomal DNA (16S rDNA), and the nuclear 18S ribosomal DNA (18S rDNA) sequences of four Prionospio species from Korean waters, P. depauperata Imajima, 1990, P. japonica Okuda, 1935, P. krusadensis Fauvel, 1929, and P. membranacea Imajima, 1990, were determined for the first time. The inter-specific genetic distances among the congeners of four Prionospio species were 22.3-29.6% in CO1, 10.5-25.0% in 16S rDNA, and 0.3-3.6% in 18S rDNA.

• 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.

• Toxicological Research
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• v.28 no.2
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• pp.129-137
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• 2012

Probabilistic ecological risk assessment (PERA) for deriving ecological protective concentration (EPC) was previously suggested in USA, Australia, New Zealand, Canada, and Netherland. This study suggested the EPC of cadmium (Cd) based on the PERA to be suitable to Korean aquatic ecosystem. First, we collected reliable ecotoxicity data from reliable data without restriction and reliable data with restrictions. Next, we sorted the ecotoxicity data based on the site-specific locations, exposure duration, and water hardness. To correct toxicity by the water hardness, EU's hardness corrected algorithm was used with slope factor 0.89 and a benchmark of water hardness 100. EPC was calculated according to statistical extrapolation method (SEM), statistical extrapolation $method_{Acute\;to\;chronic\;ratio}$ ($SEM_{ACR}$), and assessment factor method (AFM). As a result, aquatic toxicity data of Cd were collected from 43 acute toxicity data (4 Actinopterygill, 29 Branchiopoda, 1 Polychaeta, 2 Bryozoa, 6 Chlorophyceae, 1 Chanophyceae) and 40 chronic toxicity data (2 Actinopterygill, 23 Branchiopoda, 9 Chlorophyceae, 6 Macrophytes). Because toxicity data of Cd belongs to 4 classes in taxonomical classification, acute and chronic EPC (11.07 ${\mu}g/l$ and 0.034 ${\mu}g/l$, respectively) was calculated according to SEM technique. These values were included in the range of international EPCs. This study would be useful to establish the ecological standard for the protection of aquatic ecosystem in Korea.

• Korean Journal of Environmental Biology
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• v.24 no.2 s.62
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• pp.138-146
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• 2006

The effects of night-lights on feeding by the black rockfish Sebastes inermis in the cage of the Tongyeong marine ranching area were investigated by analyzing the stomach contents of 200 individuals from July 2004 to August 2004. In night-lights groups, black rockfish consumed mainly copepoda, amphipoda and polychaeta; also those in control area fed on copepods, amphipods and polychaets. Copepods (57%) and amphipods (32%) were the major prey organisms for all study period in night-lights. While, major prey items in control area were copepods (88%). Growth of the black rockfish reared in night-lights conditions were significantly higher than that of those in control area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.411-422
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• 1986

Diets of the rock trout, Agrammus agrammus, in the shore area of Tongbaeksom, Pusan over the period of July 1981 to June 1982 were studied. Specimens were sampled by angling. Stomach analysis showed that the rock trout fed mainly on epibenthic food in the littoral zone along the coast of Tongbaeksom. The food organisms of the enviornment were studied by means of underwater sampling around the angling area for this study. Although the food items of the fish changed slightly with season and age-group, main food items were Amphipoda (Gammaridae, Caprellidae) and Isopoda (Sphaeromidae, Idotheidae). This suggests that the diets of A. agrammus mainly comprised epibenthic food. Food diversity increased with age. The fish almost consummed on smaller food in size, but had selective predation according to food size, i. e. on larger food as age increases. These data provide additional support for the importance of the detritus-benthos-consummer type food chain.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.2
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• pp.168-175
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• 2013

The feeding habits of the black-edged sculpin Gymnocanthus herzensteini were studied using 944 specimens collected from February 2011 to January 2012 in the coastal waters off Mukho, Gangwondo, Korea. The G. herzensteini ranged from 11.8 to 36.3 cm in total length (TL). The percentage of empty stomachs in G. herzensteini was 40.2%, and the main prey items were Pisces, Euphausiasea, and Macrura. The smallest size group (11.8-15.0 cm TL) consumed mainly Polychaeta and Amphipoda. The quantity of prey increased in proportion to sculpin size. The composition of prey items and feeding habits of G. herzensteini exhibited seasonal fluctuations, that is, the main prey items during spring were Euphausiasea, whereas those during other seasons were Pisces.

• Korean Journal of Ichthyology
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• v.24 no.1
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• pp.35-40
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• 2012

The feeding habits of yellowback seabream, $Dentex$ $tumifrons$, were studied using 317 specimens collected in the coastal waters of Busan, from January to December, 2004. The size of the specimens ranged from 10.2 to 27.8 cm in standard length (SL). D. tumifrons had turned out a carnivore and opportunistic predator that consumed mainly shrimps. Fishes were next important prey items. Its diet also included anomurans, amphipods, crabs, echinodermata and cephalopods. Polychaetes, stomatopods, bivalves, ostracods, mysids and so on were minor preys. The individuals of smallest size class (10~13 cm SL) fed mainly on shrimps. In the next size class (13~16 cm SL), the proportion of shrimps decreased, whereas the consumption of anomurans, echinodermata and crabs increased. The proportion of these prey items decreased as body size increased, whereas the consumption of fishes gradually increased. Fishes accounted for almost stomach contents of larger individuals (more than 25 cm SL).

• Korean Journal of Ichthyology
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• v.22 no.1
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• pp.41-48
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• 2010

The feeding habits of Chaenogobius gulosus were studied based on an examination of the stomach contents of 333 specimens collected between October 2008 and September 2009 in the coastal waters of Tongyeong, Korea. The specimens ranged in standard length (SL) from 2.0 to 12.6 cm. C. gulosus is an omnivore and consumes mainly seaweeds (such as Ulva pertusas), crabs and gastropods. Its diet also included small quantities of bivalves, polychaetes, insects, shrimps, mysids and amphipods. Smaller individuals (<6 cm SL) consumed mainly gastropods. The proportion of these prey items decreased with increasing fish size, and this decrease paralleled the increased consumption of seaweeds. Seasonal changes in the diet of C. gulosus were significant. Seaweeds were consumed more during spring and summer compare with other seasons.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.1 no.2
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• pp.73-79
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• 1996

This study was conducted to investigate the faunal composition and distribution patterns of macrobenthic community in the deep sea sediments of the KODOS area, the northeastern Pacific Ocean during May 1996. Benthic animals were collected at 25 stations using a spade type box corer. Sediments were sieved through -.3 mm mesh screen. A total of 17 faunal groups in 9 phyla and 363 specimens were identified. Nematoda was the most abundant faunal group which accounted for 30.0% of total abundance. Other dominant faunal groups were foraminiferans (25.1%), harpacticoids (10.2%), xenophyophores (5.2%), and polychaetes (4.7%), Polychaeta was a typically dominant component of macrobenthic community in the study area except traditionally recognized meiofauna taxa. Mean occurrence number of faunal taxa was ca. 6 per 0.01 m$\^$2/, and mean density was estimated as 1,288 indiv./m$\^$2/. The abundance of whole fauna and that of each faunal group was highest at the surface layer of sediment, and decreased monotonously along the sediment depth; 98% of faunal abundance was found within 10 cm depth layer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.10-17
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• 1999

Feeding Habits of Acanthogobius flavimanus collected from the eelgrass bed in Kwangyang Bay from January to December 1994 were studied. A. flavimanus was a carnivore which consumed mainly polychaetes, crabs, shrimps, gammarid amphipods and fishes. Its diets included small quantities of ophiuroids, gastropods, bivalves, caprellid amphipods, isopods and tanaids. It showed ontogenetic changes in feeding habits. Small individuals fed mainly on polychaetes and amphipods. While the consumption of polychaetes and amphipods decreased with increasing fish sin, the consumption of shrimps, crabs and fishes increased. A. flavimanus fed diverse prey organisms in adult stage. The relative proportion of the major prey items changed with season. Although the consumption of polychaetes, shrimps and gammarid amphipods was relatively high in spring and autumn, A. flavimanus fed various prey organisms in nearly equal proportions in the other seasons.