What is the main contribution of zooplankton in the aquatic food chain?

Zooplankton serve as a crucial link in aquatic food chains by converting phytoplankton and other primary producers into a form of energy that can be consumed by larger organisms, such as fish and marine mammals. They are primary consumers, feeding on microscopic algae and bacteria, and in turn, are a vital food source for higher trophic levels. Their presence helps maintain the balance of aquatic ecosystems by regulating phytoplankton populations and facilitating nutrient cycling. Overall, zooplankton play a key role in energy transfer and ecosystem health in aquatic environments.