If only we all had wings to fly us south for the cold, harsh winter. Here’s what you need to know about migrating birds.
Why do birds migrate?
Although most of us don’t have the money or resources to have a winter home in the warm south, birds have the advantage of wings to take them to their tropical destinations. Along with some species of butterflies, fishes and mammals, many birds are known to migrate in order to improve their chances of survival, especially during the cold winter season. Migrating birds often travel south to ensure more food, and to reproduce.
Many insect-eating birds migrate to southern areas when winter rolls around because there is no longer an adequate supply of bugs to consume. But when the northern winter is over, these migrating birds come back to the northern region where there won’t be as much competition for food.
Although migrating birds experience many dangers along their journey, overall the trip south is more beneficial for the species as a whole even though some individual birds may perish during their migration. Migrating birds may experience setbacks during their trip like bad weather, a lack of food and predators.
How do birds know when to migrate?
There are many hints birds get which clue them in on when to migrate, but like much of animal survival, migrating birds rely heavily on natural instincts to know when to head south. The photoperiod, or the amount of sunlight each day, can affect or trigger migration. A bird’s brain can register how much sunlight there is and whether is increasing, like in the spring, or decreasing, like in the autumn. The more sunlight there is, the more opportunity there is for birds to gather food, so once the amount of sunlight begins to lessen birds know it’s time to migrate. Of course, the photoperiod only applies to birds living in temperate zones where the ratio of sunlight changes.
Just before migrating, birds can become very restless. You may hear or witness a lot more bird activity as winter approaches and they gear up for the long journey. Many species of migrating birds build fat reserves by adding larger amounts of food to their diets just before departing. This is to ensure the birds will have enough energy for the trip and also in case there is a shortage of food along the way. Migrating birds seem to have figured out the best way to handle the harsh winter.
