Just been having a look through a few wesites and found this article describing the likely hood of certain marshland birds to be soon breeding again in the UK. such species as purple heron, night heron, cattle egret, great white egret are all featured, and with the recent success of the black wing stilts who knows what is possible! heres a link anyway
http://forests.org/archive/europe/mabifrom.htm
http://forests.org/archive/europe/mabifrom.htm