• 한국양식학회지
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• 제3권1호
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• pp.89-125
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• 1990

소라 Batillus cornutus (LIGHTFOOT)의 종묘생산 기술개선과 치패발생장에 있어서의 서식생태와 소라서식장내에서의 성게류와 해조류와의 상호관계에 대한 기초자료를 얻기 위하여 1988년 4월부터 1989년 11월까지의 조사자료와 1981년부터 조사된 자료를 비교 검토하였다. 소라친패의 산란유발 자극방법으로서 야간지수후 60분간 간출자극후 자외선조사해수를 유수한 것의 산란율은 $10.00\%\~39.77\%$의 범위였다. 천연치패발생 및 성육장은 최간조시간 2시간노출지대의 암반위에 유용해조류가 번무한 곳에서 이루어지며 각고 30$\~$40mm 이후부터 점차 인근 양식어장으로 이동되는 것으로 보였다. 소라 양식어장내에서 주식이 되는 해조류 중 미역이 고사되는 6월부터 11월까지는 감태, 모자반 등의 기타해조류의 서식양이 제한요인으로 나타났다. 고수온기의 저비중에 대한 소라의 내성에 대하여는 수온 $29.5\~31.4^{\circ}C$에서 소라의 각고 30$\~$60mm의 것이 비중 1,010에서 20시간만에 폐사하였고 비중 1,015에서는 55시간만에 폐사하였다. 소라의 조도에 따른 섭이이동에 있어서는 19:00 시부터 이동이 시작되었고 23:00시부터는 전 개체가 섭이활동을 하게되고 05:00시부터는 먹이에서 이탈하기 시작하여 09:00시부터는 섭이활동이 중지되었다.

• 한국수산과학회지
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• 제49권3호
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• pp.376-384
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• 2016

Seasonal catch distributions of large purse seines and daily landings of coastal set nets were analyzed to understand the migration path of the Spanish mackerel Scomberomorus niphonius around Korean waters. The Spanish mackerel start to move toward the coastal region in the South and West Sea in May for spawning and stay until July, when spawning finishes. Afterwards, they start to migrate to the East China Sea and the southern East Sea and are found irrespective of the onshore and offshore regions. Therefore, they disappear from the offshore region during the spawning season in June and July, and a new recruitment population of age 0 begins to inflow into the coastal fishing grounds in the South Sea and West Sea in August, one month earlier than in the Japanese coastal region of the East Sea.

• 한국어류학회지
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• 제17권3호
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• pp.205-216
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• 2005

한국 남해안에서 2003년~2004년의 4월, 6월, 8월에 멸치 알의 분포 및 해양환경 특성을 비교하고 냉수대 형성과의 관계를 분석하였다. 조사해역의 수온은 $10.2{\sim}30.7^{\circ}C$, 염분은 25.7~34.7, 클로로필은 $0.14{\sim}0.67{\mu}g/L$, 동물플랑크톤은 $111.52{\sim}262.37mg/m^3$의 범위였다. 멸치 알은 수온 $14.7{\sim}26.9^{\circ}C$와 염분 31.0~34.6 범위에서 주로 나타났고, 봄에서 여름으로 진행될수록 고수온과 저염분역에서 출현하였으며, 동물부유생물 생산의 증가와 함께 알의 평균분포밀도도 높아졌다. 2004년 8월의 멸치산란장은 외양의 난류수와 연안 냉수대간의 수온전선 외해측 해역에 집중되는 경향을 보이므로 연안역의 냉수대형성이 멸치 산란장분포의 제한요인이 되는 것으로 분석되었다.

• 한국수산과학회지
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• 제38권5호
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• pp.331-341
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• 2005

Distribution of anchovy (Engraulis japonica) eggs and larvae was studied in the southwestern sea of Korea in July and November, 2001. Anchovy eggs were found mainly in the oceanic fronts of the northern sea area which were formed in the offshore area of Chuja Is. Bogil Is. and Chungsan Is. from west to east. Anchovy eggs were also found in the surrounding sea of Cheju Is. in the southern sea front area. The waters were highly heterogeneous and the water masses were bordered based on temperature $(10.8-26.4^{\circ}C)$ and salinity (28.9-33.7 psu). The anchovy eggs were mostly found outside of the China Coastal Water, where salinity was below 31 psu. The anchovy eggs were not found in November. Abundance of the anchovy larvae were higher in July than November. Temperature ranged from $10.8^{\circ}C\;to\;25.9^{\circ}C\;and\;15.9^{\circ}C\;to\;20.5^{\circ}C$, and salinity ranged from 28.9psu to 34.1psu and 33.2psu to 34.1psu in July and November, respectively. Non-swimmable larvae were found throughout the whole area of the southwestern sea of Korea. The area beyond the oceanic front had anchovy eggs dispersed from the spawning grounds to offshore. Dispersion pattern showed that the eggs were transported from the spawning grounds with a process of advection and diffusion based on the flow pattern which were caused by winds. Distribution pattern of the anchovy eggs and larvae may be used for the prediction of oceanic currents in each area.

• 한국환경생태학회지
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• 제30권4호
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• pp.684-693
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• 2016

낙동강과 금호강 합류부에 인접한 대명유수지는 멸종위기종인 맹꽁이의 집단 산란처로 생물서식공간의 보전 필요성이 높아지고 있으나, 맹꽁이 개체군에 대한 과학적인 조사가 미흡하다. 이에 본 연구에서는 포획-재포획방법에 의해 대명유수지에 서식하는 맹꽁이 개체수를 추정하며, 미지형과 식생분포를 토대로 분류한 서식처별 방형구 배치를 통해 맹꽁이의 공간분포 특성을 살펴보았다. 2013년부터 2년간 진행된 조사에서 맹꽁이는 5월초 출현하여 7월과 8월에 활동이 증가하고, 10월말에 동면에 들어가는 것으로 나타났다. 개체군 크기 추정을 위해 실시된 2014년 1차 조사에 98개체를 포획하여 표식 후 방사하였으며, 2차 조사에서는 표지된 5개체를 포함한 68개체를 재포획하여 대명유수지에 서식하는 맹꽁이는 대략 535-2,131개체로 추정하였다. 또한 대명유수지의 맹꽁이 개체군 공간분포를 파악하기 위해 평지 식생군락, 사면부, 저습지 등의 서식처에 57개 함정트랩을 배치하여, 맹꽁이의 이동이 활발한 장마철 전후를 대상으로 현지조사를 실시한 결과, 맹꽁이는 대명천과 인접한 사면부에서 출현밀도가 높고, 저지대는 출현밀도가 낮은 것으로 나타났다. 저지대의 맹꽁이 출현밀도는 산란철에 상대적으로 높으나 산란 이후에는 급격히 감소하였는데, 이는 산란 이후 은신처, 월동지로 이동하는 맹꽁이의 행동습성과 더불어 저지대가 지하수위 상승으로 대부분 침수되면서 서식환경이 악화되어 주변 경사지와 평지 식생군락으로 이동하기 때문으로 판단된다.

• 수산해양기술연구
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• 제52권2호
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• pp.121-129
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• 2016

The distribution of eggs and larvae of mackerel, Scomber japonicus was examined in the coast of Jeju island, Korea in spring from April to May in 2013 and May to June in 2014. In the monthly variations of mean abundances, as a whole, mackerel eggs were observed abundantly in April, 2013, and mackerel larvae were observed abundantly in June, 2014. Especially, high densities over $5,000ind./1,000m^3$ of mean eggs abundances were observed in the eastern part of Jeju Island where is water temperature was over $18^{\circ}C$. It can be inferred that these areas were major spawning grounds of mackerel around Jeju island, and that it may be caused by influences of the Tsushima warm current.

• 한국수산과학회지
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• 제36권2호
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• pp.120-128
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• 2003

Fishes were caught by a set net in the coastal waters off Yosu, Korea from April to October, 2001, and seasonal variation of abundance and species composition were studied. Fifty two species were identified as fish $(89\%)\;cephalopods\;(10\%)\;and\;crustaeans\;(1\%).$ Of the fishes Engraulis japonicus, Trachurus japonicus and Trichiurus lepturus were dominant species representing $64.1\%$ in total number of individuals. The number of species was high in spring and low in summer; number of individuals was high in spring and low in autumn. The diversity index (H') was 0.4-0.7 The abundance and species composition fluctuated seasonally. Occurrence of the various stages of fishes indicated that Scombia japonicus, T. japonicus and E japonicus utilized in the area as spawning ground, Conger myriaster larvae, Ammodytes personatus and Seriola quinqueradiata as nursery ground, and T. lepturus and Ilisha elongata as spawning and nursery grounds.

• 한국수산과학회지
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• 제54권4호
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• pp.498-507
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• 2021

Ichthyoplankton (fish eggs and larvae) were collected seasonally collected from 2017 to 2019 to clarify whether Dokdo serves as a fish spawning and/or nursery ground. Fish eggs were identified and classified into 16 species. The dominant fish egg species were Engraulis japonicus, Maurolicus japonicus, and Parajulis poecilepterus. Fish larvae were identified and classified into 15 species. The dominant fish larvae species were E. japonicus, M. japonicus, and Sebastes owstoni. A cluster analysis similarity percentages revealed two distinct groupings according to sample location (stations) with E. japonicus and M. japonicus as the main group influencers. E. japonicus was the dominant species off Dokdo. The species diversity and abundance peaked in summer. The diversity index, richness index, and evenness index fluctuated seasonally. There were no predominant species variations among the years. Sedentary species such as P. poecilepterus, Semicossyphus reticulatus, and Glyptocephalus stelleri occurred in the inshore stations. E. japonicus, M. japonicus, and Trachipterus trachypterus occurred in the offshore stations. Our results show these species use Dokdo as spawning and nursery grounds.

• Journal of Ecology and Environment
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• 제31권1호
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• pp.45-67
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• 2008

Ocean climate variables ($1900{\sim}2005$), time series of catches ($1910{\sim}2005$) and body size data were used to assess the year-to-year and decadal scale fluctuations in abundance of the fish populations (Japanese sardine, anchovy, jack mackerel, chub mackerel, Pacific saury and common squid) that have spawning grounds in the East China Sea and its adjacent regions. A negative correlation between the abundance of pelagic fishes (e.g. jack mackerel) in the Tsushima Warm Current (TWC) region and the Kuroshio-Oyashio Current (KOC) region was attributed to the climatic modulation of larval transport and recruitment, which depends on the winter monsoon-induced drift, current systems, and spawning season and site. The changes in abundance and alternation of dominant fish populations in the two regions in the 1930s, 1970s, and late 1980s mirrored changes in the climate indices (ALPI, AOI and MOI). Oscillations in the decadal climate shifts between the two regions led to zonal differences in larval transport and recruitment, and hence differences in the abundance of the pelagic fish populations. During deep Aleutian Lows, as in the 1980s, larval transport from the East China Sea to the KOC region increases in association with the strong winter Asian monsoon, cool regime and increased volume transport of the Kuroshio Current systems, whereas during a weak Aleutian Low (as in the 1990s), larval transport to the TWC region increased in association with a weak winter Asian monsoon, a warm regime, and increased volume transport of the Tsushima current system. We postulate that the increased chub mackerel abundance in the TWC region and the decreased abundance in the KOC region in the 1990s are partly attributed to changes in recruitment and availability to the fishing fleets under the warm regime in the spawning and nursery grounds in the East China Sea in association with the quasi-steady state of mild winter monsoon in the 1990s. The fluctuations in chub mackerel and jack mackerel abundance are under the environment-dependant growth form, although the tropicalization was identified in the TWC region. The density-dependant growth form was found in Japanese sardine populations, but no tropicalization by fishing was identified in the long ($10{\sim}15$ year) periods of abundance despite their short ($3{\sim}4$ year) generation time, suggesting that the environment-dependant growth form drove the changes in abundance. Year-to-year and decadal scale variations in abundance and population structure of the Pacific saury responded to climate regime shifts (1976/1977, 1988/1989), suggesting that the fish is a key bio-indicators for changes in the ecosystem.

• 수산해양교육연구
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• 제24권4호
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• pp.507-515
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• 2012

이 논문은 우리나라에서 바다거북의 산란이 확인된 제주도 서귀포시 예래동 중문해수욕장에서 산란지의 환경 조건을 조사 분석한 연구 결과이다. 바다거북이 산란장소(nest, 보금자리, 알을 묻는 구덩이)까지 이동하는 거리(비말선에서 산란장소까지의 거리)는 음력 20일이 음력 1일과 10일보다 짧게 조사되었고, 산란지의 깊이별(상공 5cm, 표면, 모래 속 10cm 모래 속 30cm, 모래속 50cm) 온도는 약 10일 간격으로 측정한 결과, 바다거북이 산란한 알이 정상적으로 발생하는데 요구되는 모래 속 온도인 $25^{\circ}C$ 이상의 온도는 site 1의 경우에는 2008년 6월 23일부터 9월 29일 까지 유지되었고, site 2의 경우에는 2008년 6월 23일부터 10월 17일까지 유지되었다. site 1, 2의 연안 수질 측정 결과, 수온은 2008년 6월 23일부터 11월17 일 까지 $20^{\circ}C$ 이상을 유지하였고, site 1에서 $17.83{\sim}29.88^{\circ}C$, site 2에서는 $17.98{\sim}29.94^{\circ}C$의 범위였다. 그리고 수온 이외의 연안 수질 분석 결과는 일반적인 제주도 남부 연안의 해양 수질 조건이었다. 결국 중문해수욕장은 바다거북이 상륙하여 백사장에서 산란할 경우 산란된 알이 정상적으로 발생하여 부화 가능한 조건을 갖추고 있음을 알 수 있었다.