Many states have teal seasons in September that allow harvest of blue-winged teal, which are very early migrants. In early fall, male bluewings are in their dull (aka eclipse or basic) plumage, so distinguishing males from females is not obvious. The video link below shows that it is easy to tell drakes from hens, and juveniles from adults — at least when they are in hand. I wish you good luck if you are getting out for teal.