Person having outdoor meal identifying man in photo with hesitation (9)

'person' is the definition.
(picnicker is a kind of person)

'man in photo with hesitation' is the wordplay.
'man' becomes 'nick' ().
'in' indicates putting letters inside.
'photo' becomes 'pic' (short for picture).
'with' says to put letters next to each other.
'hesitation' becomes 'er' (sound made while hesitating - um, er).
'pic'+'er'='picer'
'nick' inserted inside 'picer' is 'PICNICKER'.

'having outdoor meal identifying' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.

Can you help me to learn more?