I found it odd that there was just one of each type of duck, along with a whole bunch of mallard ducks and some Canadian geese. I guess these two got lost. A brief read of the description of gadwalls does say they are sometimes with widgeons, so I guess if the two are a gadwall and a widgeon it might make sense to see those two together.
Sorry the pictures are a bit blurry. I was experimenting with my camera earlier and forgot to adjust the ISO back to a reasonable value. I didn't notice the problem until after the ducks had swam away.