• Korean Journal of Environmental Biology
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• v.20 no.4
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• pp.312-315
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• 2002

Impact of artificial illumination on zooplankton dynamics has been studied in Tongyong marine ranch during the period from August 1998 to August 1999. Monthly sampling has been carried out to collect zooplankters from both natural waters and artificially illuminated waters at night. A total of 48 taxa of zooplankton occurred during the study. Copepods showed the prosperity in species number with 21 species. Every sample from illuminated waters consisted of move than 15 species except February while less than 15 species in samples from natural waters during the winter. Benthic amphipods occurred abundantly in illuminated waters. Zooplankton abundance was revealed to be increased in illuminated waters mainly due to the gathering of amphipods (4,500 indiv. $m^{-3})$ in September and October. Twenty times of zooplankton abundance was recorded in illuminated waters when compared with that in natural ones in September due to the gathering: of amphipods and ten times by the explosion of N. scintillans in August 1999. However, no distinct difference in the abundance was observed between two waters in the winter. Zooplankton gathering with artificial illumination seemed to be effective in amphipods, while copepods were hardly affected by the artificial illumination at night.

• Journal of Aquaculture
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• v.16 no.2
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• pp.84-87
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• 2003

Effect of artificial illumination on feeding by the rockfish Sebastes schlegeli receiving no synthetic feed in the cage of the Tongyong Marine Ranch was investigated by analysing the stomach contents of 20 individuals every month from October 1998 to July 1999. The fish was found to have fed on naturally available zooplanktons, i.e. Calanus sinicu, zoeae, amphipods and copepodites in October, fish larvae in November-December, nematodes in January, amphipods in February and again fish larvae from May to July. Despite increase in the weight of stomach contents from 260 mg/fish during the initial period of study to 2,173 mg/fish, as many as 70% of the fish were found to have empty stomach during March-April. Weight of stomach contents did not increase with increasing age of the fish. Occurrence frequency was 83-90% for C. sinicus during October-November and >50% for fish larvae during March-April and June-July.