one common formation of migrating birds is the v-shaped, which is most commonly used by geese. this pattern increases flight efficiency, allowing birds to expend less energy.
this is essential for birds that fly long distances. one reason this formation helps them conserve energy is that each bird flies at a slightly altitude.
this difference allows each to benefit from the upwash of air from the wings of the bird in front of it. this reduces the amount of resistance that the bird must overcome.
every bird that is behind another experiences this reduction, but the lead does not. therefore, when it gets tired, it moves to the back, with another bird taking its place.
*formation :대형, 진형 *upwach:상풍류(올려흐름)