zooplanktoni
Zooplankton is a diverse group of microscopic animals that drift in bodies of water. The term "zooplankton" refers to both the larval and adult stages of many animals, including crustaceans, jellyfish, copepods, and tiny fish. These organisms are found in all oceans and freshwater environments. They are a crucial part of aquatic ecosystems, serving as a primary food source for larger marine life such as fish, whales, and seabirds.
The size of zooplankton varies greatly, from microscopic protozoa measuring less than a micrometer to larger
Their life cycles are often complex, with many undergoing significant transformations from their larval to adult