4. Ring-necked Parakeet

In many parts of the world including its native range, the ring-necked parakeet is considered an invasive species.

In the UK we still think of it as either an exotic curiosity or local nuisance.

Should we be worried or continue to welcome this unlikely addition to British bird life? Derek Mooney intends to find out.

Telling the stories of non-native invasive species and our complicated attitudes to them and with an uncertain political future, how do we police our ecological borders?

Producer: Ellie Sans

First broadcast on BBC Radio 4 in August 2016.