Sounds like they're copying Wyoming regulations.
That's standard in Wy. Talked to a couple game wardens there and they both recommended. Boning out all meat at kill site and proof of sex, and the tail to show if it was a white tail or mule deer in a zip lock with your punched tag. And to keep that zip lock with your boned out meat. I hunted in Wy and then stopped on the way home and hunted a Mt tag and stopped at a couple Mt check stations. I was a little nervous having a pair of antelope and a couple deer in the freezer from WY. With the zip locks, with sex and tail and tag. They just shrugged and "yep, that's the Wyoming way".
I think it's a great system and a great way to do it. Really clean and nice, and easy for a hunter that's packing things out. I mean. Come on really.... someone's going to have a tail and proof of sex from something other than what the meat is from.... The whole prof of sex naturally attached is a PIA and BS for guys that are hunting in the back country, boning out and packing meat. It's something that should be changed. I like how Wy does it. Sounds like Mt and is going that way as well. Sure be nice is Wa did as well.