Why Birds Migrate: 9 Interesting Facts About Migratory Birds
As the cold sets in, birds leave their homes and strive to reach warmer regions as soon as possible. We, the wingless beings, can either envy or admire the birds' abilities. They don't need passports, visas, or long waits at airports to one day rise into the sky and embark on their journey.
However, birds undertake long journeys not out of romantic notions. They do not migrate because they are cold. Their feathers keep them warm even at low temperatures (down to -10, -15 degrees Celsius).
The reason is that in such cold weather, the food birds eat becomes unavailable. The ground freezes, and all the bugs and spiders hide, plants wither, and the birds remain hungry. This is the primary reason for their migrations.
Interesting Facts About Migratory Birds
● V-Formation Flight
Flying in a V-shaped formation, a flock of birds travels almost 70 percent faster than a lone bird. This is because the heart rate of birds in a flock slows down, and they glide for most of the journey as each bird flies in the air currents created by the bird in front. The leader of the flock is in the most disadvantageous position. When it gets tired, it moves to the middle of the flock, and another bird takes its place.
● Limited Food During Migration
During migration, flocks often cannot feed properly, as opportunities to obtain food are very limited. Where do they get the energy for such a strenuous task? When preparing for a long journey, we usually think ahead about our nutrition. Similarly, birds prefer to eat well before the trip to accumulate as much fat as possible for the long migration.
● Storks Can Sleep in Flight
Storks can sleep for up to 10 minutes right in flight. A tired bird simply moves to the middle of the flock and falls asleep briefly, soaring in the air current created by its neighbors. During sleep, storks' hearing sharpens, helping them maintain altitude and orientation in space.
● Migratory Instinct
Previously, it was believed that the necessity for migration developed in birds over many centuries and became so ingrained that it is inherited. They were thought to be like robots, already programmed for wintering sites and migration routes. But clever experiments have shown that this is far from the truth. A good example is the sedentary ducks of England. Scientists took eggs from English ducks and placed them with Finnish ducks, which must migrate for the winter. The foreign-born ducks flew with the locals without hesitation.
● Speed of Return Migration
Birds always try their best to return home as quickly as possible—banding data shows that the return speed is usually significantly higher than the departure speed. However, spring arrival is closely linked to the onset of warmth in breeding areas.
● Typical Altitude of Migration
1,500 meters is the usual altitude at which migratory birds travel. However, some species are true altitude champions: geese, for example, often flying over the Himalayas, ascend to heights of up to 8 km above sea level. For comparison, airliners fly at an altitude of 10-11 km.
● Wingspan of the Wandering Albatross
The wingspan of the wandering albatross reaches 3.5 meters. This bird is aptly named—it spends most of its life in flight, landing only to feed its chicks.
● Heart Rate During Flight
1,000 beats per minute is the heart rate of most birds in flight. In a calm state, the heart rate drops to 400 beats per minute.
In summary, the fascinating world of migratory birds reveals their incredible endurance and adaptability, driven primarily by survival needs rather than mere whimsy or discomfort from the cold.
