zooplanktons

Zooplankton are microscopic animals that drift in bodies of water, playing a crucial role in aquatic ecosystems. The term "zooplankton" is derived from the Greek words "zoon" meaning animal and "planktos" meaning wanderer or drifter. They are heterotrophic, meaning they cannot produce their own food and must consume other organisms. Their diet typically consists of phytoplankton, which are microscopic plants, as well as other zooplankton.

Zooplankton are incredibly diverse and include a wide range of organisms, from tiny single-celled protozoa to larger multicellular invertebrates like copepods, krill, and larval stages of fish and other larger animals. Their size varies significantly, from less than 0.1 millimeters to several millimeters, with some larger individuals found in the planktonic community. They are found in virtually all aquatic environments, from the surface layers of the ocean to freshwater lakes and rivers.

Their life cycle is often closely tied to the availability of phytoplankton. During blooms of phytoplankton, zooplankton populations can increase rapidly due to abundant food resources. Zooplankton serve as a vital link in the food web, transferring energy from primary producers (phytoplankton) to higher trophic levels, including fish, marine mammals, and birds. Their distribution and abundance are influenced by factors such as water temperature, salinity, nutrient availability, and ocean currents. They are sensitive indicators of environmental changes and are therefore important for monitoring the health of aquatic ecosystems.