Not being sarcastic but do you really know how many birds you've killed in your lifetime? I've never heard of anyone whose kept track?
Yes, I actually have. Got the sickness 11 years ago when I was 19 and it came on strong. Kinda a data junkie so I’ve kept logs of all my hunts. Where, when, with whom, #of each species killed and drake/hen count. Used to keep track of weather each day too but I’ve gotten lazy and haven’t done that the last couple of years. Haha
I had a few years where I shot both bluewings and cinns on the same day and found this to be true. The bluewing's bill tended to be a bit narrower but without the cinn to compare to, I would never have been able to distinguish.
I know many folks that keep track... I have since my first duck in 1978... It’s the least I can do for killing it just for fun...
I have kept a detailed hunting journal for all 45 years I've hunted. Fun to look back. I even keep my dogs' retrieve numbers. I like data also.