Hi Colin A
Welcome to the Forum.
“the “reversing” , one hog makes the loud sniffing noise, it might approach another but then “goes into reverse” and backs off” will be a male and female. The female reversing and huffing. Part of the ‘courtship’.
Yes, the biffing and rolling up (and along) is just what hogs do. They have ranges rather than actual territories and their ranges overlap. But males, if they are more dominant tend to biff any male that comes into their personal space. That’s more likely to happen at feeding stations, because they’re more likely to meet there, but it does happen elsewhere as well.
Sometimes it turns into more of a fight, as you mentioned. Hogs here have on occasion been seen to shake another hog like a terrier with a rat, but that happens very much more seldom than the biffing and rolling. I suspect that they recognise each other and know the other hog is more dominant or otherwise and react accordingly. I wouldn’t worry about it. It seems it isn’t as bad as it first appears – they have all those spines to cushion them. But as you say, they normally just carry on as normal once the aggressor has moved on.
It is quite possible that your garden is in the middle of one particular hog’s range so that he visits more often. I have found in the past that the females tend to visit more regularly, i.e. most nights, and tend to stay in the same area whilst the males visit a bit more infrequently. They have larger ranges than the females, and so have more opportunity of finding food, but also other females elsewhere.
You’ve obviously worked out how to identify which are males. The females are the ones that behave as you described, backing and huffing, but also the ones who turn round and round huffing whilst the male circles around her during courtship.
I wrote some notes a while back with some tips on how to identify hedgehogs by their natural markings which you might find useful:
I hope you decide to have a go at natural identification.
Good luck and happy hog watching.