Zooplankton - Study methods, importance and significant observations

Abstract

The intent of this section is to review briefly current knowledge of the structure and dynamics of the zooplankton and its ecology. Zooplankton are mysids of animal organisms that drift with currents. In an aquatic ecosystem zooplankton form an important link in the food chain from primary to tertiary level leading to the production of fishery. It has been well established that potentials of pelagic fishes viz. finfishes, crustaceans, mollusks and marine mammals either directly or indirectly depend on zooplankton. By virtue of sheer abundance and intermediatary role between phytoplankton and fish, they are considered as the chief index of utilization of aquatic biotope at the secondary trophic level. The herbivorous zooplanktons is efficient grazers of the phytoplankton and have been referred to as living machines transforming plant material into animal tissue. Hence they play an important role as the intermediaries for nutrients/energy transfer between primary and tertiary trophic levels. Due to their large density, shorter life span, drifting nature, high group/species diversity and different tolerance to the stress, they are being used as the indicator organisms for the physical, chemical and biological processes in the aquatic ecosystem. In the deeper water they occur at different depths and constitute a complicated ecological system worthy of special attention.