Was the program called 'Wildlife on One'? I punched in David Attenborough's name into the UKNova search engine and found that. They currently have two episodes of 'Wildlife on One' up, but it sounds like this is the one you are talking about:
Kea: The Smartest Parrot
David Attenborough narrates a documentary about the kea, the world's only alpine parrot. Playful and destructive, it attacks cars, starts landslides and terrorises New Zealand ski resorts but behind the bad behaviour there's a sharp mind at work. David tries to play chess with a kea and discovers how its cheeky character is the key to its survival.
If anyone really wants one of those episodes I can download it and upload it to Hokiethang's FTP (as long as he doesn't mind having some non-car related stuff on the FTP for a while).