Squirrel, for example, not red? That's strange! (6)
I believe the answer is:
rodent
'squirrel for example' is the definition.
(I know that squirrel is a type of rodent)
'not red? that's strange' is the wordplay.
'that's strange' indicates anagramming the letters.
'not'+'red'='notred'
'notred' with letters rearranged gives 'RODENT'.
(Other definitions for rodent that I've seen before include "Toothy mammal" , "Eg, mouse, squirrel" , "Eg, capybara" , "Small gnawing mammal" , "Gnawing creature" .)