Some time in the early 70s I bought an old reel-to-reel tape recorder and somewhere on the tape was this song, though the lyrics were slightly different:

Where be that blackbird be?
Where be that blackbird be?
'E be up yon wurzel tree
And Oi be aafter 'e.
'E sees me, and Oi sees 'e.
Underneath yon wurzel tree
With bloody big stick Oi wallop 'e
Blackbird, I'll 'ave' e'.

Sung in an exaggerated fake-Devon "Wurzels" accent.