Why do grazing animals still need to migrate?

1. because eventually the grass/food they are eating will loose its nutrients from eating it all the time and they need to migrate to find better food

2. the weather

3. their predators may migrate to the place they are and they need to migrate in order to have a better chance of survival

hope this helps these are just some reasons just ask if you need anymore

the millers tale is the answer.

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