Bird in menu that changes (8)
I believe the answer is:
nuthatch
'bird' is the definition.
(nuthatch is a kind of bird)
'in menu that changes' is the wordplay.
'in' says the answer is hidden in the clue.
'NUTHATCH' can be found hidden inside 'menu that changes'.
(Other definitions for nuthatch that I've seen before include "Songbird feeding on insects and kernels" , "Singer" , "small bird" , "Tree-climbing songbird" , "warbler?" .)