Ok from the book:
Badgers by Ernest Neal/Chris Cheesman (Poyser 1996):
Half of all
Badger mortalities take place on roads, this is about 37,500 animals annually.
It also goes on to state that weather conditions play a major role, especially dry weather when the Badges have to forage further for food, often on unfamiliar ground. Living in larger groups also put more pressure on them in dryer weather.