Bird found in pile of hay (4)
I believe the answer is:
cock
I believe this is a double definition.
'bird' is the first definition.
(cock is a kind of bird)
'pile of hay' is the second definition.
(I've seen this before)
'found in' is the link.
(Other definitions for cock that I've seen before include "Pull back a gun's hammer in readiness to shoot" , "Small heap of hay" , "bull to > raise for shooting" , "Prepare to shoot" , "small pile of hay" .)