Bunnies often like to explore or even sit in the gap between the wall and the back of your couch. There are good reasons why this should be avoided.
It can lead to chewing damage building up without you noticing which if unchecked can cause quite a lot of damage and even give your bunny access to the inside of the couch where your bunny can get stuck.
Your couch may also not be as static as your bunny imagines and if it moves suddenly when someone sits down it can be pushed back, trapping and hurting them.
Your couch may also not be as static as your bunny imagines
It's always best to block off this area before any of these problems occur using one of the following bunny proofing methods in this guide like filling the space plastic strange tubs.
We also have some examples of using a wooden frame to make behind you couch permanently bunny proofed.
To help stop your couch moving about make sure it is pushed back fully up against the wall. If it's on wheels or can easily slide about you may want to use some coasters to help hold it in place.
Couches are often odd shapes so even if you have pushed it back you may also need to cover the gaps that is left between the couch and the walls. A simple way to do this is to with a few well-placed sturdy ornaments at each end or by moving some other bits of furniture up against it to cover over the gap.
Another simple solution can be to fill the space with something you want to store away that is resistant to being chewed. Plastic storage boxes are ideal for this as they are cheap and come in a variety of sizes so you can pack the gap out. They can also be a great way of hiding things away from your bunny like shoes or toys to stop them being chewed.
A more solid way to cover over the sides is to add some fencing to block it off. A common way to do this is to use some wooden or acrylic sheets or by breaking out a few sections of pet pen fencing. These can be lashing to the sides with some string or trapped in place by placing a heavy ornament up against them. It's best to avoid using cardboard as this can easily be chewed through and may prove more of an encouragement.
If you are handy with DIY a permanent solution can be to first build a frame under your couch which can be used to stop your bunny getting underneath and then to build the sides up to cover the gap by attaching a few bits of wooden board.
Some people go as far as putting a shelf or wooden frame behind the sofa to keep it all boxed in.