Kiltit glad it helps. I get out a lot but got to say I don't kill a lot. The public land I hunt can be real hit and miss. I have a lot of days of never even reaching for the shotgun but then again I have one of those days where everything goes right and I know I maybe getting older but another day like that could be just around the bend so I just got to be out there when it does. Most of the time I can tell from how they fly to necks or even the shape of the wing what I got coming in but because I don't put a ton of birds in my hands sometimes just like you I'm not real sure of what I got , gads, widgons and pintail hens can look a lot alike heck early in the year you may think you shot a mallard hen only to find out when it's in your hand it's a drake that just ain't colored out yet. Just remember if you're not sure in the field what you have ( look it up when you get home) just pick your shots at birds that you're sure of,,, oh say like mallard drakes with bright green heads. You might not kill as many birds but it's sure alot less expensive then if the GW shows up to tell you what you got over the limit........
ENJOY YOUR TIME AFIELD
Mike