The effect of phytoplankton abundance on zooplankton behavior during the day and night in the waters of the northern Peninsula of the Banyuasin Coast, South Sumatra

Abstract

Plankton has an important role and can be used as a bioindicator of water conditions. The abundance of phytoplankton and the behavior of zooplankton are interrelated, namely the interaction of prey and predators. Phytoplankton form community structures and zooplankton community structures give rise to feeding strategies as predators. The purpose was to observe the behavior of zooplankton at the time of observation based on the level of abundance of phytoplankton. This research was conducted in October 2020 in the waters of the northern peninsula of the Banyuasin coast, South Sumatra. Sampling of plankton using a horizontally pulled bongonet for 5 minutes. The results showed that the abundance of phytoplankton contributed indirectly to the behavior of zooplankton, differences in time and environmental conditions such as tides and temperature also contributed. The highest abundance of phytoplankton was found at station 4 at night with an abundance of 71553 cells/m3, while the highest abundance of zooplankton was at station 5 at night 1332 ind/m3. The distribution of the movement of zooplankton in the study waters is below during the day and begins to increase in abundance at night, this is indicated by the behavior of zooplankton looking for prey at night with the main target being phytoplankton.