Satapoomin, S. Phuket Marine Biological Center/University of Copenhagen, pmbcnet@sun.phuket.ksc.co.th
Nielsen, T. National Environmental Research Institute, tgn@dmu.dk
Schou, O. National Environmental Research Institute, oleschou@get2net.dk

 
ROLE OF ONCAEA SPP. IN THE TROPICAL ANDAMAN SEA
 
The present study focuses on the trophic role of the cyclopoid copepod, Oncaea spp. in the tropical Andaman sea. Measurement of standing stock and production was conducted along transects from the coastal zone across the shelf to the deep offshore water. The transects were investigated in both the wet and dry seasons. Species diversity of the copepod community is high, about 100 species. The population of small cyclopoid copepods contributed with 30 % of the total biomass, documenting the key role of this group in the pelagic food web. Of these, Oncaea spp. contributed with 10% of the copepod standing stock, with highest value observed in the dry season. Egg production of O. venusta was calculated from clutch size, (90-130 egg per female), and hatching rate (ca. 25% per day) at sea surface temperature. The specific egg production rate followed the same pattern as the calanoids, with a peak on the coastal site of the shelf break front. Temporal and seasonal variation in biomass and production will be discussed in relation to hydrography and potential food items (chlorophyll, ciliates and dinoflagellates). Preliminary results from gut fluorescence and grazing experiments indicated that O. venusta rely primarily on microzooplankton rather than phytoplankton.
 
Day: Tuesday, Feb. 2
Time: 02:15 - 02:30pm
Location: Hilton of Santa Fe
 
Code: SS23TU0215H