Experimental studies on food habits of tropical microzooplankton: (Prey-predator interrelationship)

Abstract

A laboratory study was conducted to investigate the herbivorous activity of tintinnids and rotifers. It was revealed that, in tintinnids the lorical diameter plays an important role in the selection of prey species. The ingestion rates of the tintinnids increased when the prey cell-size decreased. Tintinnids were observed to feed mostly on nannophytoplankters of cell width less than 30 mu m, namely Nitzschia closterium and Asterionella glacialis. The cyanobacterial species were preferred more by the rotifers as their diet, compared to tintinnids. The rotifers such as Brachionus plicatilis and Keratella tropica were ingested more cyanobacterial species like Anacystis dimidiata and Phormidium fragile. It was evident from the experimental studies that the size and shape of the prey organisms such as diatoms and cyanobacteria play an important role in the feeding interrelation and interactions of microzooplankton.