• Korean Journal of Ichthyology
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• v.35 no.4
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• pp.361-365
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• 2023

On May 12, 2023, a juvenile specimen (37.6 mm in standard length) belonging to the order Aulopiformes was collected from southern Yokjido, Tongyeong, Korea, using a Bongo net. The specimen was identified as the member of the family Scopelarchidae in having a slender body, a large mouth, large tube-like eyes, a long anal fin base, a developed adipose fin and no photophores on body. Finally, we identify the specimen as Scopelarchoides danae Johnson, 1974 in having 8 dorsal fin rays, 20 pectoral fin rays, 9 pelvic fin rays, 26 anal fin rays, dorsal fin located anteriorly than pelvic fin, and two large pigments below the pectoral fin and posterior to the pelvic fin. Scopelarchoides danae is distinguished from Scopelarchoides signifer in having less dorsal fin rays (8 vs. 9~10) and pectoral fin rays (20 vs. 22~25). The species differs from Scopelarchus guentheri and Scopelarchus analis in that it has no stripes along the both upper and lower of lateral line, and from Scopelarchus michaelsarsi in that it has more anal fin rays (26 vs. 18~21). Because this is the first occurrence among Korean fish fauna, we present its detailed morphological traits, and its new Korean name as "Nun-bang-ul-mae-tung-i".

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.737-747
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• 1999

To estimate biomass and distribution of the Antarctic krill (Euphausia superba), hydroacoustic survey was conducted on board of R/V Yuzhmorgeologiya, which was chartered by Korea Antarctic Research Program (KARP) group from 18 to 21 December 1998, in the northern part of the South Shetland Islands, Antarctic Ocean, The scientific echo sounder (towing body type) used was EK- 500 (SIMRAD, Norway) with echo integrator (BI-500) at 38 kHz frequency and recorded mean backscattering cross-section coefficient (SA) per 1 $mile^2$ of sea surface. Also, Bongo net sampling was carried out to determine the size of krill and CTD (Conductivity, Temperature and Depth) casting to understand physical structure. Water column was divided into 5 layers (22$\~$65 m, 65$\~$115 m, l15$\~$65 m, 165$\~$215 m and 215$\~$315 m) to know vertical distribution of krill biomass. The standard length of krill collected was between 30 mm and 51 mm, and adult krill had single mode (41 mm). Maximum horizontal length of krill patch was about 35 nautical mile and vertical thickness was about 275 m. High density of krill was appeared in frontal area between Circumpolar Deep Water (>$1^{\circ}C$) and very low temperature water mass (< $-0.5^{\circ}C$) that originate from Weddell Sea. According to the results calculated using target strength equation, krill density was totally higher in continental slope and open water areas than in coastal area. In the study area, krill seems to distribute in depth; density was low at first layer ($\={\rho}=17.0\;g/m^2$) and higher at fourth layer ($\={\rho}=40.19\;g/m^2$). The estimated krill biomass at total survey area and water column was about 2.77 million metric ion ($\={\rho}=151.0\;g/m^2$) and coefficient of valiance ( CV, $\%$) was 19.92. The proportions and biomass of krill biomass at each layer were as follows; layer 1 ($11.3\%$, 0.31 million metric ton, CV=16.24), layer 2 ($13.3\%$, 0.37 million metric ton, CV=34.91), layer 3 ($23.7\%$, 0.66 million metric ton, CV=41.5), layer 4 ($26.6\%$, 0.74 million metric ton, CV=27.84) and layer 5 ($25\%$, 0.69 million metric ton, CV= 26.83).