Fish migration is the mass movement of fish from one area or body of water to another, are in one way or another an important part of the life cycle of fish and are divided into types:

- by direction - horizontal and vertical;

- method of movement - passive (drifting) and active;

- in relation to the current - denatant and counter-denatant;

- Relation to salinity - potamodromous (in fresh water), oceanodromous (in sea water) and diadromous (from fresh water to the sea and back);

- Holobiotic and amphibiotic in relation to environmental factors;

- length - far migrating and migrating on short distances.

Denatant migration is the mass movement of fish downstream to their spawning grounds.

In some fish, the spawning migration is part contra- natant, part denatant.