Bird Quiz

Can anyone tell me what bird this is?  I've looked at so many web sites trying to identify it, but nothing matches.  The bird is eagle size, blackish brown, with a white tail, yellow hooked beak and yellow legs. I thought it was a Great Black Hawk, but I'm not sure because of its yellow beak.

Photo taken at Shelter Bay Marina, Panama

Thank you for all your responses, apparently this is the  Common Black Hawk