Most drift.
They are too weak and small to fight against the current.
The term "plankton" refers to organisms that drift with the ocean's currents. Although some krill can swim and would thus be classed as "nekton," since they can move independently of the currents, most are considered plankton.
Plankton is the mass of mostly microscopic organisms that float or drift freely in freshwater and marine environments and Nekton are all organisms the swim actively in open water, independent of currents.
The ocean sunfish, Mola mola, is not a plankton. Its a nekton which means it has the ability to swim and direct itself through waters. It can decide where to go and can fight against some ocean currents. Plankton cannot do this, they drift along with the currents.
Plankton.
Plankton in most cases does not swim, but merely floats. As for microscopic animal plankton (zoo-plankton) it is moving such small distances at such low speeds that it encounters negligible water resistance.
Plankton
Plankton
Plankton.
Plankton.
Plankton refers to small organisms that drift or float in aquatic environments, unable to swim against the current. They serve as a vital food source for many aquatic organisms and play a key role in the marine ecosystem. Plankton can be broadly classified into phytoplankton (plant-like) and zooplankton (animal-like) based on their primary composition.
dead plants and animals that drift from the surface