Bird and elk - rest moving about (7)
I believe the answer is:
kestrel
'bird' is the definition.
(kestrel is a kind of bird)
'elk rest moving about' is the wordplay.
'moving about' indicates anagramming the letters.
'elk'+'rest'='elkrest'
'elkrest' anagrammed gives 'KESTREL'.
'and' acts as a link.
(Other definitions for kestrel that I've seen before include "Les, trek around the bird" , "Predator" , "It takes mice" , "High flier" , "Falcon that hovers" .)