Hunt's changing of gear (6)
I believe the answer is:
forage
'hunt's' is the definition.
(foraging is a kind of hunting)
'changing of gear' is the wordplay.
'changing' is an anagram indicator.
'of'+'gear'='ofgear'
'ofgear' anagrammed gives 'FORAGE'.
(Other definitions for forage that I've seen before include "Rummage, go searching" , "look around" , "Collect food" , "Plunder; rummage" , "Rummage, search for" .)