Measures taken after duke's trapped by game birds (11)
I believe the answer is:
goldfinches
'birds' is the definition.
(goldfinch is a kind of bird)
'measures taken after duke's trapped by game' is the wordplay.
'measures taken' becomes 'inches' (I can't explain this - if you can you should give a lot more credence to this answer).
'after' means one lot of letters go next to another.
'duke' becomes 'd' (abbreviation).
'trapped by' is an insertion indicator.
'game' becomes 'golf game' (golf is an example).
'd' inserted into 'golf' is 'goldf'.
'inches' put after 'goldf' is 'GOLDFINCHES'.
Can you help me to learn more?
(Other definitions for goldfinches that I've seen before include "Songbirds" , "Small birds" .)