Some kinds of fish are born in rivers, but swim away from the place they were born and live their lives elsewhere. When they are ready to reproduce (spawn) they swim back to where they were born to lay eggs or fertlise them. So they migrate downriver to live, and migrate back upriver to spawn.
Salmon are born in fresh water, migrate to the ocean and then return to the fresh water to spawn. Salmon have the reputation of returning to the same place they were born in order to spawn.
Anadromous: Relating to fish, such as salmon or shad, that migrate up rivers from the sea to breed in fresh water.Catadramous: Migratory pattern in which juvenile fish spawn in the open ocean but mature in freshwater.
Digging holes is just something many cichlids do. It may mean the fish is getting ready to spawn but in the case of the (Laboratory made) Parrot cichlids, it is unlikely you will get fertile ova if they do spawn.
The answer is spawn
Some fish migrate. Except for the monarch, most butterflies do not migrate.
fish that can spawn up to 100,000 eggs each spawn
Salmon is one fish that travels up a river to spawn.
I don't know exactly what you are asking. Milkfish (Chanos chanos) are spawned in the ocean and eventually migrate to fresh water where they grow on to become adults. Once they are adult they migrate again back into the ocean to spawn. I assume their life cycle is the opposite to the Salmon who live in the ocean but return to the fresh water to spawn.
spawn
no it dose not migrate
No, they don't migrate.
* 2 fish in love with each other * 2 fish breeding * A beautiful dance that fish do during mating season