The birds flew South for their migration in the Winter.
Example sentence - The hummingbirds were ready for their migration south for the winter.
He has studied the migration patterns of several bird species for eight years.
The Great Migration made an impact on the Northern States.
I enjoy watching the Least Tern's yearly migration.
use it as the first word e.g. migration is what birds do to survive
All you people have to use the migration stream when you go to another country!
In the winter the bear went into a cave untill the winter was over, thats called migration.
There were migratory butterflies.
The nouns in the sentence are hibernation and migration, compound object of the preposition 'by'.
The migration of European storks spending the winter in Africa require no visa.
There is a simple migration path from rental to investment in property.
Early people did not cultivate food, so they had to resort to continual migration to the places where the food naturally occurred