http://www.slate.com/id/2209166/

Turkey vulture advocates want us to know that the birds do not circle over dying things; the implication of the common cartoon image of vultures above the crawling man in the desert is slanderous, says Lynch. The birds circle as they ascend on thermals—columns of warm rising air. If, as choreographers say, grace is the elimination of extraneous movements, their flight is graceful. They ride air currents for hours with no flapping. They rock and sway, ranging over dozens of square miles, returning to roost sociably with their fellows in late afternoon.