Mallard

It could also be a male Mexican Duck (Anas diazi)

i think you might be right about it being a mottled duck. In person the bill had a greenish yellow color. It could be a male Western Gulf Coast Mottled Duck (Anas fulvigula maculosa)

A mallard would have a white edge to the speculum, yours has a black edge. A female mallard also has an orange bill with black markings on it, yours has a solid yellow bill

Thanks! i was trying to decide mallard or teal.