No, the first time they were fighting they were out in the garden and we were watching them. There could be a few reasons.
1. They both like to run about quite crazily. I have noticed that whenever Willow accidently bumps into Fudge, Fudge gets a bit miffed and sort of blanks her for a few hours, Fudge runs away whenever Willow goes near her.
2. Willow wants to be top bun, hence the humping, that has sort of calmed down recently though.
3. (And this is really thinking outside the box) Recently, two neighbourhood cats have been skulking around the garden. Whenever I check on them/feed them in the morning and let them out after work they are always there just watching outside the hutsch until I chase them off. Perhaps the cats have made them anxious? My buns are outside buns (I know this forum is for house rabbits, but it’s the only forum I can access from work)
From everything I have read, this behaviour of ‘fighting’ for dominant position is normal, and it crops up every so often and it calms down after a tussle, but that doesn’t stop me worrying that I am coming home to injured (or worse) buns!