Woman appearing to be a pescatarian (5)
I believe the answer is:
heron
'a pescatarian' is the definition.
(bird that eats fish)
'woman appearing' is the wordplay.
'woman' becomes 'her' (her refers to a woman).
'appearing' becomes 'on' (as in 'who's on TV tonight?').
'her'+'on'='HERON'
'to be' is the link.
(Other definitions for heron that I've seen before include "Grey or white long-legged wading bird" , "Big bird" , "Graceful grey bird with long neck" , "flier" , "Rhone (anag) - bird" .)