Yes, Delilah does barbering as one of the side effects of the neglect she experienced as a baby before she came to me. It’s gotten MUCH better over the years but still resurfaces occasionally like all her stereotypic behaviours. She will be grooming Lahi, usually his shoulders, when suddenly instead of licking she’ll grab a huge hunk of fur and start pulling until it comes out. Poor little man had very bald shoulders. Nothing I did helped, until I started putting little shirts on Lahi. She would still sometimes pull on the fur still exposed on the side of his arms but it’s his shoulders she’s really interested in.
I also work with mice and I’m now not really sure how typical Delilah’s style of barbering is. When mice start overgrooming it’s not actually yanking on the fur, it is literally just licking the other mouse so much that they go bald. The fur around their noses and their whiskers are usually the first to disappear, followed by their shoulders. One set of mice I saw that were in a study on stereotypic behaviours had all groomed bald a patch of fur on the others’ shoulders that was so perfectly rectangular and even, on every single mouse, I had to ask one of the research students if they had perhaps shaved the mice for some sort of injection or surgery. “God no,” I was told, “we wish we could get that clean a shave. That’s the overgrooming.”
Delilah has actually done this form of overgrooming as well. After Lahi had the tumor removal surgery on his ear, his ear was highly sensitive and he wouldn’t let Delilah touch it. But she was very insistent on trying to groom it, and when she wouldn’t be allowed to touch the one ear, she ended up grooming the back of the other ear, and it very quickly developed its own bald spot.
In any case, from my experiences with barbering/overgrooming, what you’re describing does not sound like that. It sounds like hormones.
I encourage you to get them spayed regardless of being both female. “If they’re both female they won’t have to be fixed” is a belief many people have when they get bunnies, myself included. Lahi ended up being male so did have to get neutered, but I never got Picca spayed and deeply regretted it. As mentioned, females are at a huge risk of cancer when not sterilized, and Lahi has now lived longer without his sister than he ever did with her. Literally her potential lifespan was cut more than in half because she wasn’t fixed.
Moreover, when she was still alive, getting her to live with Delilah without attacking her took well over a year. Lahi accepted Delilah within a month, not so with Picca. They coexisted in grudging peace for a couple months before one fur-flying fight ruined it and they never forgave each other. Until the day Picca died, they couldn’t even be on either side of cage bars without trying to bite each other’s face. Trying to integrate a new rabbit with a an established rabbit when they’re not fixed is generally accepted to be extremely difficult and in my experience was TOTAL HELL.
And just because your girls get along now doesn’t mean they always will. As mentioned, one bad fight is enough to ruin it all. My difficulty likely stemmed from trying to introduce a new female to a female who was defending her very established territory, but I’ve heard of many people who had two sisters who eventually had to separate them. Delilah is included in this, one of the reasons her neglect was so bad was that she was all alone in her tiny rabbit cage with no company. She was originally sharing the space with her sister Scarlett, but when Scarlett and Delilah started fighting they had to be separated. When her owner got bored of her she had absolutely no company and went completely nuts, trapped alone in her cage.
There is always a risk when it comes to surgery, but for a vet who knows what they’re doing, a rabbit spay is actually much easier than spaying most other animals, as their reproductive organs are very close to the surface of the skin. The only real increased risk involved is that their airways are too small for most people to be able to intubate them, and so don’t have a recourse for AR if they stop breathing. But that’s not exactly a common occurrence.
Lahi is 12 years old and has to undergo surgery every year since 2014 to trim his teeth. This year he had an echocardiogram due to a small heart murmur and bloodwork done to check his kidney values and make sure he is still safe to undergo anesthesia, and everything came back “no issues expected”. For someone who knows what they’re doing, surgery in rabbits is not any more concerning that surgery in any other animal, humans included.