The version I was told when I was little is

Where be that blackbird be,
I know where 'e be,
'e be up that cider tree,
and i'll be after 'e,
'e sees I and I sees 'e,
bugger if I don't get him,
With a bloody great stick I'll knock 'im down,
Blackbird I'll have 'im,
da da da da da da, da da da da da da,
hows ya father .... alright.