Extraordinary bird gathering first of twigs (9)
I believe the answer is:
startling
'extraordinary' is the definition.
(I've seen this before)
'first of twigs' is the wordplay.
'first' becomes 'start' (synonyms).
'of twigs' becomes 'ling' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'start'+'ling'='STARTLING'
'bird gathering' is the link.
This may not be right. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for startling that I've seen before include "Unexpected" , "staggering" , "Surprising or alarming" , "Causing shock" , "Rattlings of alarming kind" .)