Previously good natured male now aggressive?

Question
Hi Lee

We have a 5 month old buck called Patch (crossbred lop/rex) with a previously great temperment in that he'd get on with any new rabbit we'd bring in, even in his hutch or play area. He was living with his "partner" but when she fell pregnant recently, moved him into a new hutch with a our lionhead male Rolo, they would get on just fine and eat together and follow each other around etc, however after we introduced another male, a baby dwarf called Magic to their hutch & run he has started rubbing his chin on anything he can and has become aggressive towards Rolo, chasing him away whenever he comes anywhere near him and biting him a lot. As a result Rolo has now become very nervous. However he's now adopted Magic as his "playmate" and is fine with him. We've decided to move Patch into solitary confinement, another hutch on his own for a couple of days so Rolo can get his scent on the old hutch and make it his territory and then try and introduce Patch again. Is this the right thing to do?

Answer
Hi Danny,

my answers back to you hinge on a couple of assumptions I have to make because I am not certain of them from your letter.  I am assuming all your rabbits are intact, and that you have tried putting three intact sexually mature male rabbits together in the same cage space.

First, intact rabbits are going to be naturally more aggressive than neutered rabbits.  There is no way around this fact.  They have much higher hormone levels, and these hormone levels will drive them to act more aggressively in cases of establishing dominance (which always occurs when two or more rabbits are together), and for battling for females.

Second, rabbits pick their friends (like people).  Patch was fine with his female, but then you moved him in with an intact male Rolo, which is competition.  Shortly after that you move a third male in with them and perhaps Rolo and Patch hadn't settled the dominance issue and another rabbit is added to a potentially hormonally charged situation.  Patch probably already has decided he is the alpha bunny because he was the one who had the female, and he is expressing dominance to make sure the other two know it ,that he's not taking a back seat to them.  So in my opinion you're not doing any of them any favors by throwing them all together like this in such a short period of time without doing any kind of bonding processes.  It's a recipe for injury.

Third, once a female is pregnant, you should always separate the male from her.  He still wants sex, and she will want nothing to do with him and will be harassed by him to the point fighting will break out.  So it was good you made this move.

My advice is to keep Patch separate from the other two rabbits.  If they are getting along fine together, do not mess it up by putting Patch back in with them.  Keep Patch separate, maybe closer to his girlfriend, but not in the same cage space or exercise space.  Pregnant females don't want to be around any other rabbits and actually don't want you or anyone else around them either.  

Keep in mind you may have to separate your two boys Rolo and Magic at some point, as the two-male pairs will fight, even if they get along most of the time.  It may come to a point where they can't be in the same cage.  It is even going to happen if they are neutered.

To reduce aggression in both the female and the males, the solution is simple: get them altered.  You'll have no unwanted litters and they will get along with each other better than they do now, because the hormonally-driven behaviors that lead to fighting will be greatly reduced, if not eliminated.  Besides, in America anyways, we have such an oversupply of rabbits for the demand, thousands of perfectly good and healthy rabbits are put down at shelters because they are no longer wanted.

Hope this helps,

Lee