Tense description of midnight activity of bird-watchers (9)
I believe the answer is:
twitching
'activity of bird-watchers' is the definition.
I can't tell whether this defines the answer.
'tense description of midnight' is the wordplay.
'tense description of' becomes 't' (I can't justify this - if you can you should give a lot more credence to this answer).
'midnight' becomes 'witching' (I've seen this before).
't'+'witching'='TWITCHING'
Can you help me to learn more?
(Other definitions for twitching that I've seen before include "Showing nervousness" , "Obsessive bird-spotting" , "Visibly nervous" .)