Why do female dogs hump?

Yep, in my experience females tend to hump about as frequently as males. Obviously an unneutered male humping an unspayed female is generally for procreation, but fixed dogs hump each other for a variety of purposes. Sometimes it's bullying behavior, or to put a younger dog in their place. Sometimes it's a play instigating behavior, like when you playfully shove a friend to get a reaction out of them. Sometimes it's a stress reaction.. you'll find a lot of dogs who hump certain objects or other animals obsessively when they're nervous.

Dogs are really good at knowing the difference. If the dog feels like they're being bullied or pushed around, generally that's when they'll snark back at the offending dog. Younger or less confident dogs will often just submit to the controlling hump by rolling over and holding still. If the dog responds with play, then the hump was likely meant to goad them into playing. If the humpee doesn't know the humper very well, they may still snark at the playfully humping dog because they're being just a little too familiar, like you might glare at someone you barely know who playfully shoved you. Some more unflappable dogs will ignore play humpers or bully humpers, usually just walking away or barely seeming to notice anything weird is happening to them. Stress humping looks obsessive, like the dog just can't help themselves.

A female dog humping is a very natural thing. It's not a sexual thing what so ever, more often than not it either playful behavior or dominance. If it really bothers you, at the time it occurs say no and remove her off the other dog. My Husky and my Berner both females did the same thing. Had it corrected within a week or two by doing just as I said.

I have bred Airedales and Miniature Schnauzers. I no longer breed but remember I had a couple of girls who were genuine Alphas. They even didn't squat to pee but half crouched and lifted their leg to mark their territory. I think it is just an Alpha and personality thing. Humping is pretty normal. Males do it and I had a schnauzer male who had been neutered as a pup and still humped everything. He even humped my airedale girls on the shoulder. They tolerated it for the most part. Pretty funny.