ACTIVE GROWTH OF THE OCEANIC DINOFLAGELLATE CERATIUM TERES IN THE CARIBBEAN AND SARGASSO SEAS ESTIMATED BY CELL CYCLE ANALYSIS1

Abstract

ABSTRACTThe growth rate of an oceanic dinoflagellate, Ceratium teres Kofoid, was investigated in the Sargasso and Caribbean Seas from September 1989 to July 1990 using the cell cycle analysis method. Estimated growth rates ranged from 0.29 to 0.58 day−1 and were 1.5–7.2 times higher than generally accepted rates for oceanic dinoflagellates. The higher rates in this report were mainly due to an improvement in techniques that determine the duration of a terminal cell cycle phase in situ. The day‐to‐day variation in growth rates was surprisingly small, but, from long‐term measurements, a weak correlation was found among temperature, daily irradiance, and seasonal growth rate. The calculated species‐specific primary production ranged from 0.5 to 1.8 mg C·m−2·day−1, about 1% of the estimated total production. Ceratium teres may be an important carbon source at the base of the grazing food chain.