Have you ever wondered why birds fly south in the winter? Not all of them do that, but some species are well-known for their seasonal migrations. The main reasons for moving south to spend winter is the type of food birds eat and the area they live.
Many places inhabited by birds don’t provide them much food during wintertime. There’s no nectar or insects, so they are forced to look for food elsewhere.
Scientists do not agree whether birds migrate instinctively or due to some specific environmental cues. It depends on birds, too. Some of them will delay migration as long as they can find something to eat.