More southerly breeding populations don’t migrate as far. Geese from the most northern populations travel to the farthest south. Rather than migrate nonstop to their wintering grounds, many geese travel in stages, pausing at traditional stopover sites to rest and regain lost fat. They’ll end up on the Atlantic Coast and migrate south following the shoreline. For example, geese that pass by my house in Northern New York follow the Atlantic flyway. Most geese that breed in a particular region will migrate along similar routes, called flyways. The younger geese, which are not as strong, line up along the V behind the lead parent. Recently, ornithologists have discovered that when families migrate together as a flock, the parents take turns at the tip of the V. When it gets too tired, it drops back and another takes the lead. It is working much harder than the others. The bird at the point of the V, in the front of the flock, gets no advantage from drafting. The same physics explains why fighter jets fly in V formation to conserve fuel. And little pockets of spinning air, called vortices, produce lift that helps keep a trailing bird aloft. The flapping of the bird ahead creates a forward movement of air called a slipstream, which helps pull the trailing bird forward. Following another bird at the right distance blocks any headwind. This form of drafting, also called vortex surfing, saves a lot of energy. When all flock members do this, the familiar V shape appears. To reduce drag and to receive a little extra lift, geese fly close behind and about one wing length to the side of the one immediately in front. In addition, they have another energy-saving trick. To reduce the effort, geese fly at night when the air is calmer, or in the day when there’s a helpful tailwind they avoid flying into a headwind that would blow them backward. Geese work very hard during migration flights. All this flapping for a heavy bird takes a lot of energy. Geese are heavy birds, and they fly fast – over 30 miles per hour – using powerful wing beats, rather than gliding like eagles or vultures. Flocks of geese are called movie#People who have raised and socially bonded with geese have even taught the birds new migration routes by leading them in an ultralight aircraft – as in the movie “ Fly Away Home.” Young geese learn the migration route and landmarks by following their parents and other experienced geese. Geese have a physical compass in their head that allows them to tell north and south by detecting the Earth’s magnetic field. They may also use celestial cues such as the sun and stars. Geese navigate based on experience, using landmarks including rivers, coastlines and mountain ranges. Geese fly by day or night, depending on factors like weather conditions or brightness of the moon. Single families of geese, or flocks of several families together, take off and head south. Maybe you’ve observed flock members signaling they’re ready to go: They honk loudly and point their bills toward the sky. Once conditions become so tough that they can’t find enough to eat, geese migrate. They usually remain in their summer range until the weather is cold, water starts to freeze, and food gets hard to come by. They migrate continuously, except for short stopovers to fuel up on insects, fruit, or seeds before continuing on their way.Ĭanada geese and other migratory geese species are different. Flocks of geese are called how to#Most migrate at night, individually rather than in flocks, and they know where to go and how to get there without guidance from parents or other birds.
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