Abstract:

Abstract During the CHINARE XV cruise in austral summer of 1998/1999, the abundance and feeding activity of salpa thompsoni were estimated in the Prydz Bay region. Salps samples were collected by vertical tows from 200m to the surface with a conical net of 330μm mesh size. At Ⅳ 3 station, the grazing rates were estimated by the gut fluorescence method and culture experiments. S.Thompsoni mainly distributed in the northern part of the survey area, and its maximum densities was reached to 2795ind. 1000m -3 . A dramatic decrease in salp stock was observed at the marginal ICE Zone. The results of the feeding experiments at the Ⅳ 3 showed: The gut pigments levels of S. Thompsoni was 0.14-1.27μg·ind. -1 (average 0.98μg·ind. -1 ). The individual ingestion rate was 7.9μg(chla)ind. -1 d -1 , and the filtration rate was 28 l·ind. -1 ·d -1 . Through the daily grazing rate of S. Thompsoni was less than 1% of the phytoplankton standing stock, it showed a grazing impress on the primary production (72.2%). [WT5HZ]