This will likely stop when you and he have developed a relationship of mutual trust. Meanwhile it is important that he realizes that he has nothing to gain from charging and biting. It’s good that you stayed in his area post-bite, because if you flee, the animal immediately learns that biting will make the hoomin go away. Rabbits are flight animals like deer and llamas and horses etc, so you can actually reward them by just going away.

That said, there’s no good point in trying to provoke a bite, so if it’s his enclosure he’s protective of, you could try to clean it when he’s having outside time. Since Bert is a rescue who was found with matted fur and fleas it’s likely that his encounters with humans haven’t always been positive experiences, plus if he spent time on his own outside he will have had to be pretty sassy or he’d not have lasted long. Territoriality tends to diminish a lot post neuter, especially in boy buns.

I’ve had a young rabbit who would growl and charge and even bite. He too was a rescued stray. We became the best of friends, but it did take a few months. It was as if he was torn between a wish to be pet and an urge to defend himself. Eventually the wish to be pet won.

A rabbit that bites is not like a dog that bites. If a dog bites its owner sth is wrong, dogs are bred since many, many thousands of years to not bite their human. Rabbits have only been held in captivity for a few hundred years – and it’s just these last say 50 years that they’ve been house pets. So they still retain a lot more of their wildtype behaviour than dogs do.

A lot of bunnies can become “cage aggressive”, especially when not neutered. It’s sadly possible this behavior was what led to him being abandoned (again, thank goodness you found him!)

The good news is it will very likely improve, both with neutering and as you form a better relationship with him. My first house bunny Bunston hated when we cleaned his cage if he was in it, and my bun Bonnie was also like this (after 3 years in the shelter, poor baby 🙁 ). . With her I tried very hard not to clean her enclosure while she was in it, so I would wait till she was out running around. I also only pick her up when absolutely necessary (she hates being picked up). I will reach in to fill water or give food, but I save the actually cleaning and rearranging for when they aren’t there. If I absolutely have to, I move very slowly and speak calmly to her so she isn’t startled. Buns have a blind spot in front of their face, so sometimes I think they have a hard time knowing what’s happening and think it’s an intruder.

After a few weeks with me, Bonnie’s cage aggression was almost completely better. She still hates being picked up but she won’t lunge or box at me if I reach into the pen to grab something or top up hay.

You’re so very welcome! 🙂

I imagine now that the initial shock of moving to a new home has worn off, his territorial instincts are starting to kick in again. I agree that this behavior can definitely be improved by neutering. Working on a relationship will help as well. Once he sees he can trust you, he won’t feel the need to defend himself and his area so much. You did the right thing by not fleeing after he bit you. The next step is to become associated with good things. You can try hand feeding him.