Hey OP, what did you think it was before it was shot????
What color were the eyes, yellow or red? Was the bill broad (rounded-looking) and light bluish grey a lighter line and black tip? Or was it all black and triangular profile? Was it a particularly large duck? These are all things I think somebody who is shooting at Redheads and Canvasbacks should be able to figure out since the limits on each are set pretty tight.
Take a pic of the top of the bill and we'll know who's right and who's wrong.
Wasn't born in Texas, but I got there as fast as I could.