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B I R D S

BACKGROUND:

Birds have always been called our "fine feathered friends", but suddenly, they are receiving more attention from non-scientists than any other group of animals.  Birds have a backbone and are therefore called vertebrates (a reference to the bony structure of their backs).  They are also warm-blooded because their bodies have the ability to maintain a stable, or nearly stable, body temperature even if the temperature of the environment varies over a considerable range.  Feathers cover the birds' skin layer. One use of feathers is as insulation to help maintain the birds' body temperature.  Feathers (in trunk) are also used to help birds fly.  Birds' legs and toes are covered with scales and their upper and lower jaws are covered by a protruding horn-like beak.  Birds have unusual bones that make up their skeletal systems in that the bones are hollow and contain air.  This lightweight bone type is an adaptation to aid in flying.  All birds lay eggs in nests.  Nests may be located on the ground, in above-ground locations such as in a tree, bush or tall grass, or even in man-made structures like platforms, barns, chimneys, or bridges.

Birds that feed along the shores of bodies of water (bays, lakes, or oceans) are commonly called shorebirds.  Examples of shorebirds are terns, gulls, herons, willets, and pelicans.  Most shorebirds spend only a part of the year in Florida's Gulf of Mexico area then they move on to other locations.  These journeys, called migrations, take the birds to nesting sites or to areas where they spend the winter or summer.  Some shorebirds, such as the gulls, do NOT migrate.  They stay in the same area year round and are called residents.

The ways birds feed can be used to classify them as diggers, divers, waders, swimmers and skimmers.  The birds' beaks, legs and feet are uniquely adapted to match their method of feeding.

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