Swarm of Tintinnopsis uruguayensis in the estuarine waters of Kochi, Southwest coast of India

Abstract Microzooplankton play an important connecting role in the aquatic food webs. During our bimonthly time series observation on microzooplankton ecology and dynamics in the estuarine waters of Kochi, Southwest coast of India, dense swarming of Tintinnopsis uruguayensis was noticed. The contribution of T. uruguayensis during the swarm period was 98.4% of the total microzooplankton density. The swarming of T. uruguayensis during the postmonsoon (November 2015) could be related to the higher concentrations of food supply. The results demonstrate a statistically significant positive relationship between the swarm of T. uruguayensis and the small centric diatom Thalassiosira decipiens . Our observation suggest that the increase of Thalassiosira decipiens contributed to the proliferation of T. uruguayensis .