My NSH likes to bite and nip when you 1) halter 2) bridle 3) clean his front feet (nips you in the back or the butt!). In other words, anytime you are near her face she likes to nip and bite. Usually it's nipping, but once in awhile she gets ahold of you and it's a nice pinch. How do you train a horse not to nip and bite? She's very mouthy and her former owner said she always has been. She's busy with a bit in her mouth too, usually gnawing on it. Any HUMANE suggestions? And no, I won't jab her with a tack or a nail when she does it.
I hope you know that she ain't thinking of the HUMANE thing when she's biting you.
I'm assuming you've never really been bit. Horses can crush bone. Seriously. And don't think she won't eventually get there. Bad behavior escalates.
I had a nippy horse when I bought him. He did not respond to traditional whack in the jaw, or having his feet moved, so I would simply keep him out of my space at all times. He tried to enter into my space, he would get an elbow in the face. This didn't even give him a chance to get close to biting me. I would just flap my elbows, and then continue what I was doing. Wouldn't look at him, wouldn't yell, just a "get out of my space." He thought he was running into me, similar to the nail thing that Cherie suggested. If this had not worked, I would have done the nail thing (as that would have gotten his attention even more). The horse is NOT thinking about your well being or whether she is being treated humanely, she is trying to dominate and hurt you. Period.