ANIMALS: "BIRDS"; THE FLIGHT OF BIRDS

 The flight of birds:

    The birds seem to fly effortlessly. Nothing could be further from the truth. Take-off is the most dificult phase.The wings work best when they receive the action of the wind. Therefore, as long as the bird has not gained speed, it can only rely on its muscular strength. But once its cruising pace is acquired, it can save its energy by letting itself be propelled by the wind or carried by the thermal ascendances. He can even take a nap.

The sailing flight:

    Birds of prey fly high taking advantage of warm air lifts called thermal lifts. To do this, they must describe curcular movements. After being mounted at the top of the hot air column, they can hover hanging for miles without the slightest flap of wings.

The sails of birds;

    Thousands of starlings can form dark clouds, abruptly spread when the birds descend in a dive one after the other. A group flight offers several anvantages. If it shifts a little, laterally, each bird benefits from the upward vortices generated by the flapping wings of the one preceding it. This is why ducks and geese form V-flights. Collective flight also facilitates the search for food and protects from predators.

Different styles of flights:

    Small birds fold their wings for barely noticeable breaks: their flight path keeps climbing and descending. Ducks and geese flap their wings continuously: they are fast and very vigorous, but quickly consume their energy reserves. Large birds, such as vultures and albatrosses, practice sailing and gliding, taking advantage of thermal ascendancies or the acquired speed.

Landing:

    Landing requires less effort than take-off, but requires some skill, especially for bird perchers. To lose speed, birds straighten their wings and bodies and lower their tails. Many have a clump of stabilizer feathers inserted on the thumb, alulum, which prevents them from losing their balance by slowing down.