What does migration mean?

Migration refers to the migration of residence; Migration.

Move: hand over. Transplantation. Move the carving (after a while). Shift (the shadow of the sun moves, as it is said, after a while). Immigrants. Migration. Transfer. Teaching after leaving school (taking wine to seek advice from others, generally referring to taking the initiative to seek advice).

Change: emigration. Easy to empathize (change people's feelings). Subtle. A kind of official documents in the old days, the official offices with different styles of writing: the transmission of official documents. Move it.

Historical background of immigrants:

The migration of birds occurs periodically between the breeding area and the wintering area every year, mostly between the northern and southern hemispheres and a few between the eastern and western hemispheres. People divide birds into migratory birds and resident birds according to the activities in bird migration.

Resident birds stay in their birthplace all the year round and do not migrate, such as sparrows and magpies. Among migratory birds, birds that fly to breed in summer and fly to the south in winter are called summer migratory birds, such as family swallow and cuckoo. Birds that fly in winter and breed in the north in spring are called winter migratory birds, such as some wild ducks and geese.

There is a proper term for fish migration called "migration". Most fish can be said to be migratory fish, and only a few fish do not show regular migration. Fish migration can be divided into three types according to the purpose: reproductive migration, feeding migration and wintering migration. Black carp, grass carp, silver carp, bighead carp, yellow croaker and salmon all migrate.