According to the Game & Wildlife Conservation Trust (and other conservation organisations), the big decline in Brown Hare numbers started in the late 1950's early 60's, due mostly to the reduction in agricultural diversity through intensified farming methods.
Nationally, Brown Hare have been increasing since the 1980's and the introduction of agri-environment schemes (the increase has continued since the ban). This trend applies to Roe too.
So overall, neither the Hare or Deer populations of the UK can be said to be f***ed up by GUNS, so please can we all stop blaming each other. T