American Coot 2016

Coots are dark-gray to black birds with a bright-white bill and forehead. The legs are yellow-green.
An awkward and often clumsy flier, the American Coot requires long running takeoffs to get airborne.
https://www.allaboutbirds.org/guide/American_Coot
"Coots are seen at Falls Mills Lake (Tazewell Co., VA) in the fall and winter seasons. The numbers can be 300+ when migrating southward."