Seasonal dynamics of planktonic ciliates at 4 Korean major ports: Busan, Ulsan, Gwangyang and Incheon

Abstract

Planktonic ciliates play an important role in food web of marine ecosystem as well as a bio-indicator for invade species from ballast waters or from changing flow of currents due to climate changes. This study was carried out in order to fine evidences for introduction of invade species. We surveyed the seasonal species composition of planktonic ciliate to find out the evidence for invade species ae Busan, Ulsan, Gwangyang and Incheon in Korean major ports fro February 2007 to November 2008. A total of 45 ciliate species, belonging to 14 genera, were identified during the study period. In each port, 34 species occurred at Gwangyang, 33 at Busan, 31 at Ulsan, 18 at Incheon, respectively. The abundance of naked ciliates ranged from 266 to 65,151 cells/L and that of tintinnids 10 to 5,973 cells/L.13 spp. Of tintinnids such as Eutintinnus lusus-undae, Eutintinnus tubulosus, Facella ehrenbergii, Favella taraikaensis, Helicostomella subulata, Stenisemella nivalis, Tintinnopsis ampla, Tintinnopsis beroidea, Tintinopsos cylindrical, Tintinnopsis direcra, Tintinnopsis lohmanni, Tintinnopsis radix, Tintinnopsis rapa are classified as a vector species based on a report from Coos Bay in Oregon, USA. This vector species occurred highest with 13 spp. at Gwangyang port. Most tintinnid species occurred as neritic species throughout the survey, while some warm water species occurred only for a short period at Busan, Ulsan and Gwangyang ports where Tsushima warm current might affect seasonally. It suggests that the influence of the warm water species might be affected by influx of Tsushima warm current.