• Ocean and Polar Research
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• 제41권4호
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• pp.251-263
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• 2019

We investigated the mesozooplankton community structure during autumn in the southern Yellow Sea. Mesozooplankton density generally ranged from 352 to 2,954 ind. m^-3 and varied according to different sampling stations. The copepod Paracalanus parvus s.l. and its copepodites dominated in the communities, corresponding to 57.3% in density of the total. Surface and water-column averaged salinity were positively correlated with density of total mesozooplankton, copepods and a few dominant species, and the tunicate Thalia rhomboides was negatively related to chlorophyll-a concentration. The mesozooplankton community of the study area was divided into three groups according to the cluster analysis using species composition and density: one in the northern coastal region, another in the northern offshore region, and the other in the south. The most significant indicator species for each of the groups were Labidocera euchaeta in the northern coastal region, T. rhomboides in the northern offshore region, and Themisto sp. juveniles in the south. This study provides recent data on the characteristics of the mesozooplankton community in the southern Yellow Sea, which may be valuable for gaining a better understanding of changes in the pelagic ecosystem of the Yellow Sea.

• 한국어류학회지
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• 제29권4호
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• pp.267-271
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• 2017

본 연구는 여름철 동해 남부 연안에 출현하는 청어 유어 301개체의 일섭식율 변동을 조사하였다. 어류 시료는 여름철에 3시간 간격으로 24시간 동안 소형 저인망을 이용하여 채집하였다. 청어 유어의 공위율(ratio of empty stomach), 만복도(stomach fullness), 위내용물중량지수(stomach contents index, SCI), 만복도지수(stomach fullness index, IF)는 낮과 밤의 변화에 따라 뚜렷하게 변동하였다. 공위율은 밤에 높았지만, 다른 지수들은 낮에 높아지는 경향을 보였고, 일몰 직전에 가장 높은 값을 보였다. 낮 동안 청어 유어의 위내용물은 요각류(Copepoda)와 난바다곤쟁이류(Euphausiacea)로 구성되어 있었고, 자정 근처에는 거의 소화되어 확인이 어려운 먹이생물로 구성되어 있었다.

• 한국어류학회지
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• 제10권2호
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• pp.176-183
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• 1998

우리나라 주변 해역 중 심층에서 많이 출현하며, 생태학적으로 중요한 위치를 차지하는 앨퉁이(Maurolicus muelleri)의 산란생태 및 식성을 조사하였다. 앨통이는 동해 남부 연안역을 중심으로 연중 산란하며, 주 산란기는 8월 전후로 나타났다. 앨퉁이의 난소에서 관찰된 포란수는 5,072~32,117개 범위였다. 난경은 3개의 크기군으로 구분되었으며, 0.8mm 이상 크기의 난모세포가 산란된다고 볼 때, 1회 산란수는 약 250개로 추정되었다. 앨퉁이는 동물플랑크톤을 먹는 어류로 부유성 요각류(Copepoda)를 가장 선호하였으며, 그 외에 단각류(Amphipoda), 난바다곤쟁이류(Euphausiacea), 새우류(Caridea) 및 곤쟁이류(Mysidacea) 등의 갑각류를 잡아먹었다.

• 한국수산과학회지
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• 제49권5호
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• pp.642-647
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• 2016

Postlarval and juvenile anchovies Engraulis japonicus were collected using a gape net with wings in the coastal waters of Yeosu in July and August 2015, and their gut contents were analyzed. The size range of the postlarvae was 11.0-24.2 mm (notochord length) and that of the juveniles was 25.1-37.4 mm (standard length). Guts were empty in 64.5% of postlarvae and in 51.7% of juveniles. The dominant prey organisms in the guts of both postlarvae and juveniles were copepoda. Calanoida were important prey organisms for postlarvae and were dominated by nauplii of Paracalanus sp. and Calanus sp. as well as unidentified copepod naupill. Calanoida were also important in the diets of juveniles, whose gut contents were dominated by Paracalanus sp. and Cirripedia. Gut compositions were significantly different (P<0.05) among three body size levels in postlarvae and juveniles. As the body size of the postlarvae and juveniles increased, Calanoida constituted a larger proportion of the gut contents, while the proportion of copepod nauplii decreased.

• 한국수산과학회지
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• 제30권5호
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• pp.896-902
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• 1997

1994년 1월부터 1994년 12월까지 광양만 대도주변 잘피밭에서 채집된 실고기의 식성을 조사하였다. 실고기는 요각류 (Copepoda)와 잘피의 엽상체에 부착하여 서식하는 단각류 (Amphipoda)의 일종인 옆새우류 (Gammaridea)를 주로 섭이하였으며, 그 외, 카프렐라류 (Caprellidea), 주걱벌레붙이류 (Tanaidacea), 곤쟁이류 (Mysidacea) 등을 소량 섭이하였다. 실고기는 성장함에 따라 섭이된 먹이생물 조성의 변동이 뚜렷하였다. 어린 실고기는 요각류를 주로 섭이하였으나, 체장이 증가하면서 옆새우류를 주로 섭이하였다. 먹이생물의 조성은 계절에 따라 변화되었는데, 봄철에는 요각류가, 여름철과 가을철에는 옆새우류가 주로 섭이되었다.

• 한국해양학회지
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• 제26권2호
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• pp.101-107
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• 1991

영산강 하구역에 분포하는 진주담치에 기생하는 요각류, Pseudomyicola spinosus 의 계절 변동을 조사했다. 본 종은 일년에 4세대를 영위하며 여름에 나타난 세대의 개 체수가 가장 많았다. 성비는 9월을 제외하고 6∼10월은 수컷이 1월을 제외한 11∼5월 은 암컷성체가 각각 우세하게 나타났다. 포란성체는 2월을 제외하고 연중 발견되었다. 포란성체가 많이 나타난 1개월 후에는 copeodid가 많이 출현하였다. copeodid는 1∼3 기는 전체의 약 4%에 불과하였으며, 이러한 결과는 copeodid 3기에 본격적인 감염이 이루어지고 있음을 시사하였다.

• Ocean Science Journal
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• 제42권3호
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• pp.135-152
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• 2007

The ecological aspect of meiofaunal communities in Can Gio mangrove forest, Ho Chi Minh city, Vietnam has not been investigated before. The composition, distribution, density and biodiversity of meiofaunal communities were studied along an intertidal transect at the Khe Nhan mudflat. Each time, three replicate samples were collected in four stations along a transect following the water line from low tide level up to the mangrove forest edge. In total, 18 meiofaunal taxa were found with the dominant taxa belonging to Nematoda, Copepoda, Sarcomastigophora and Polychaeta. The densities of meiofauna ranged from $1156inds/10cm^2$ to $2082inds/10cm^2$. The increase in densities from the mangrove forest edge towards the low water line was significant Along the mudflat transect, the biodiversity (expressed by different indices) was relatively high at different taxonomic levels but did not vary significantly along the mudflat except for taxa richness. Eighty nematode genera belonging to 24 families with Comesomatidae having the highest abundance 33.8 % were found. Theristus and Neochromadora decreased in densities from the lower water line towards the mangrove forest edge, while Paracomesoma and Hopperia are typical and more abundant at the middle of the mudflat. Halalaimus increased from high on the mudflat to the low water line.

• 한국어병학회지
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• 제7권1호
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• pp.47-51
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• 1994

전장 20cm 전후 크기의 양식중인 넙치 체표면에 Caligus curtus가 최고 63마리나 기생되었다. 기생 부위는 머리부분이 63.4%, 꼬리부분 26.9%, 아가미 뚜껑 8.3%, 기타 부위 1.4% 이었다. 기생된 부위는 미세한 출혈과 함께 점액이 다량 분비되었다. 이 Caligus충은 Masoten 5ppm에서 15분, 10ppm에서는 5분만에 탈락 폐사되었으나, 4시간 동안 담수욕 처리에서는 28.57%밖에 탈락되지 않았으며, 200ppm의 포르말린 30분 약욕으로는 전혀 구제되지 않았다.

• Animal Systematics, Evolution and Diversity
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• 제31권1호
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• pp.31-41
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• 2015

A new species of the genus Farranula Wilson, 1942 (Cyclopoida, Corycaeidae) is described based on both sexes collected off Chuuk Island in Micronesia (West Central Pacific). The new species F. dahlae differs from its close congener F. gibbula (Giesbrecht, 1891) in the following combination of characters in both sexes: body length is longer, length to width ratio of caudal rami is larger, basal element of maxilliped is distinctly longer, and terminal spine to distal segment ratio of P4 is smaller; while in females, lateral margins of fourth pedigerous somite are extended to mid-region of second urosomal somite, maximum width of the second urosomal somite is located at middle region in dorsal and lateral views, and length ratio of caudal seta III to seta V is much larger; and in males, sharply contracted portion of second somite is located at two-thirds distance from anterior margin. Some additional morphological details of F. gibbula are given and a key to species of the genus Farranula is provided.

• Animal Systematics, Evolution and Diversity
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• 제31권4호
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• pp.247-256
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• 2015

A new cyclopoid species belonging to the genus Metacyclops Kiefer, 1927 is described, based upon the specimens from a temporary pool in a forest of Mt. Phnom Domnak Dambouk, situated in the southwestern part of Cambodia. Metacyclops woni sp. nov. is characterized by its quite short caudal rami, about 2.5 times longer than wide, with a spinule row on anterior quarter of lateral margin. This new species belongs to the species group with the spine formula 3,4,4,3 of swimming legs 1-4. Among the members of the species group with the combination of characters of 11-segmented antennule and a single apical spine on the second endopodal segment of leg 4, it most resembles M. deserticus Mercado-Salas and Suárez-Morales, 2013 from Mexico in carrying an outermost caudal seta slightly longer than the innermost caudal seta and an apical spine on the second endopodal segment of leg 4 slightly shorter than the segment. However, it differs clearly from the present new species by much longer caudal rami with lateral caudal seta at nearly halfway of lateral margin of the ramus and smooth posterior margin of intercoxal sclerites of legs 1-4. This is the first record of the genus Metacyclops from Cambodia and the fourth one from Southeast Asia.