My male dog sniffs the backsides of my two females. All of the dogs are neutered. He does it so often that the eldest gets irritated and snaps at him.
Smell is like vision for dogs. Whereas we examine our kids or loved ones with our eyes to see how they’re doing, dogs rely on smell. It’s not known exactly how much information they glean from a good long sniff, but it seems to have more than just general health and fertility status info. Some researchers have posited that hormones released by stress could put pheremones in the dog’s scent glands* and other dogs might be able to detect it.
By hunching, do you mean she’s presenting, as in getting in position to mate, or do you mean she’s rubbing her bottom against the carpet? If the latter is the case, she might have impacted scent glands which are irritating and sometimes painful. You can empty them yourself, but I don’t recommend it. It’s a gawd-awful stink. Have your vet do it.
My eldest dog was spayed before her first birthday. When she was eight, I caught her copulating with a neighbor’s dog. I asked here on the boards and they suggested that her hormone levels might still be high enough to make her want to mate even if she wasn’t in heat.
Either way, get the dog checked out at the vet as soon as you can, just to make sure there’s nothing physically wrong. Likely, there isn’t. It’s entirely possible she’s agitated about something else and that’s just her way of acting out on it. (Maybe it’s getting ready to storm?)
In the mean time, give her a treat which will take a good, long while to eat to keep her busy. She’s not going to bug you if there’s something yummy to chew on. Fill a bone with peanut butter and give it to her** or give her a new toy. Keep her busy.
- Which is actually what the dog is sniffing. It just happens to be located next to the ass.
** In the summer, I keep a couple of these in my freezer. Keeps 'em cool and takes much longer for them to eat.