In gliding the bird descends with its wings outstretched and all surfaces expanded to slow its descent. The best gliders can travel a distance of about 20 times the altitudes from which they start to descend.
Gliding birds, such as vultures, gulls, pelicans, hawks and eagles, can travel vast distances with very little effort by rising in one updraft and then gliding till they reach another. Through wing movements they can just hover at the same height in an updraft or change from a glide to a soar in an instant. Some bird varieties can travel this way at speeds of 30 to 50 miles (48 to 80 kilometers) per hour for most of the day, thereby conserving their energy. Usually one can tell when birds use this type of flight, for they will circle for a while as they rise and then change into a long, straight glide.
Birds such as the albatross are experts at handling the strong winds over the ocean. With the wind behind it, the albatross starts a long glide toward the water's surface, gathering speed. A few feet from the water it turns into the wind and is lifted up by it, gaining altitude but losing speed. Then it turns and starts the cycle again. By adjusting the distances traveled in any part of this cycle, the bird can travel in any desired direction. By this technique, the royal albatross, for example, can travel at 50 to 70 miles (80 to 110 kilometers) per hour for long periods. The only effort required is that the bird must keep its wings extended and occasionally flap them once or twice.
Gliding birds, such as vultures, gulls, pelicans, hawks and eagles, can travel vast distances with very little effort by rising in one updraft and then gliding till they reach another. Through wing movements they can just hover at the same height in an updraft or change from a glide to a soar in an instant. Some bird varieties can travel this way at speeds of 30 to 50 miles (48 to 80 kilometers) per hour for most of the day, thereby conserving their energy. Usually one can tell when birds use this type of flight, for they will circle for a while as they rise and then change into a long, straight glide.
Birds such as the albatross are experts at handling the strong winds over the ocean. With the wind behind it, the albatross starts a long glide toward the water's surface, gathering speed. A few feet from the water it turns into the wind and is lifted up by it, gaining altitude but losing speed. Then it turns and starts the cycle again. By adjusting the distances traveled in any part of this cycle, the bird can travel in any desired direction. By this technique, the royal albatross, for example, can travel at 50 to 70 miles (80 to 110 kilometers) per hour for long periods. The only effort required is that the bird must keep its wings extended and occasionally flap them once or twice.
