I just discovered this on Mocha today. I feel so bad I didn't notice it earlier. This must have been from one week ago when he and his brother were fighting. Since then, Mocha has been moved to his new area with his girl Sapphire.
Since it's been a week, what should I do? Is it too late now and should I just let it be? Sorry the photo is so large. I wanted the wound to be visible. Now looking at it, it looks moist in the photo but it is not. It is dry and hard like a scab.
edit: I just saw I should include other info...
Mocha is neutered (and his girl is spayed). They've spent this past week in Sapphire's former territory. That is why I haven't handled him. I was letting them adjust to their new space.
They had bonded upstairs in neutral area for a month prior. I was bonding 3 -- these 2 and Mocha's brother. All went reasonably well until that last day when the 2 brothers just went at it. Sapphire & Mocha have never fought or tussled.
Both bunnies are under 2 yrs of age. Both came from rescues.