Well I've gone sneaking up on this several times now. Every day there are 3-4 new furlings and when I sneak up close enough the war starts. The mobs don't attack the buildings just each other and when the last furling dies the dragurs return to their huts. When i return a game day or 2 later the extra dragurs from the previous fight had despanwed and there were new furlings in their village. You can just barely make them out in this screen shot, but there are 3 new ones that can be seen.
https://steamcommunity.com/sharedfiles/filedetails/?id=2847009398