Atlantic Flyway

The Atlantic Flyway is a bird migration route that generally follows the Atlantic Coast of North America and the Appalachian Mountains. The main endpoints of the flyway include the Canadian Maritimes and the region surrounding the Gulf of Mexico; the migration route tends to narrow considerably in the southern United States in the states of Virginia, North Carolina, South Carolina, Georgia, and Florida. which account for the high number of bird species found in those areas. Once in Florida, the flyway diverges into a path over eastern Mexico and a longer path across the Caribbean Sea via Cuba and Jamaica.
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Waterfowl

Waterfowl are certain wildfowl of the order Anseriformes, especially members of the family Anatidae, which includes ducks, geese, and swans.

They are strong swimmers with medium to large bodies. They have historically been an important food source, and continue to be hunted as game, or raised as poultry for meat and eggs. The domestic duck is sometimes kept as a pet.

Thrust

Thrust is a reaction force described quantitatively by Newton's second and third laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system.
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alula

Feathers on the alula are not generally considered to be flight feathers in the strict sense; though they are asymmetrical, they lack the length and stiffness of most true flight feathers. However, alula feathers are definitely an aid to slow flight. These feathers—which are attached to the bird's "thumb" and normally lie flush against the anterior edge of the wing—function in the same way as the slats on an airplane wing, allowing the wing to achieve a higher than normal angle of attack – and thus lift – without resulting in a stall. By manipulating its thumb to create a gap between the alula and the rest of the wing, a bird can avoid stalling when flying at low speeds or landing.
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Primaries

Primaries are connected to the manus (the bird's "hand", composed of carpometacarpus and phalanges); these are the longest and narrowest of the remiges (particularly those attached to the phalanges), and they can be individually rotated. These feathers are especially important for flapping flight, as they are the principal source of thrust, moving the bird forward through the air. Most thrust is generated on the downstroke of flapping flight. However, on the upstroke (when the bird often draws its wing in close to its body), the primaries are separated and rotated, reducing air resistance while still helping to provide some thrust. The flexibility of the remiges on the wingtips of large soaring birds also allows for the spreading of those feathers, which helps to reduce the creation of wingtip vortices, thereby reducing drag. The barbules on these feathers, friction barbules, are specialized with large lobular barbicels that help grip and prevent slippage of overlying feathers and are present in most of the flying birds.
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Remiges

Remiges (from the Latin for "oarsman") are located on the posterior side of the wing. Ligaments attach the long calami, or quills, firmly to the wing bones, and a thick, strong band of tendinous tissue—known as the postpatagium—helps to hold and support the remiges in place. Corresponding remiges on individual birds are symmetrical between the two wings, matching to a large extent in size and shape (except in the case of mutation or damage), though not necessarily in pattern. They are given different names depending on their position along the wing.
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Flight feathers

Flight feathers are the long, stiff, asymmetrically shaped, but symmetrically paired feathers on the wings or tail of a bird; those on the wings are called remiges (singular remex) while those on the tail are called rectrices (singular rectrix). Their primary function is to aid in the generation of both thrust and lift, thereby enabling flight. The flight feathers of some birds have evolved to perform additional functions, generally associated with territorial displays, courtship rituals or feeding methods. In some species, these feathers have developed into long showy plumes used in visual courtship displays, while in others they create a sound during display flights. Tiny serrations on the leading edge of their remiges help owls to fly silently (and therefore hunt more successfully), while the extra stiff rectrices of woodpeckers help them to brace against tree trunks as they hammer. Even flightless birds still retain flight feathers, though sometimes in radically modified forms.

The moult of their flight feathers can cause serious problems for birds, as it can impair their ability to fly. Different species have evolved different strategies for coping with this, ranging from dropping all their flight feathers at once (and thus becoming flightless for some relatively short period of time) to extending the moult over a period of several years.
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