High-flyer once seen going with papers for shredding (9,6)
I believe the answer is:
passenger pigeon
'high-flyer once' is the definition.
I can't tell whether this defines the answer.
'going with papers for shredding' is the wordplay.
I cannot quite see how this works, but
'going' could be 'on' (both can mean functioning or activated) and 'on' is found in the answer.
'papers' could be 'pass' (pass is a kind of papers) and 'pass' is present in the answer.
This may be the basis of clue (or it may be nonsense).
'seen' acts as a link.
Can you help me to learn more?
(Other definitions for passenger pigeon that I've seen before include "Extinct migratory bird" , "long-distance flyer" .)