Bird looking to eat lugworms, primarily (8)
I believe the answer is:
starling
'bird' is the definition.
(starling is a kind of bird)
'looking to eat lugworms primarily' is the wordplay.
'looking' becomes 'staring' (staring is a kind of looking).
'to eat' indicates putting letters inside.
'lugworms primarily' becomes 'l' (I can't justify this - if you can you should give a lot more credence to this answer).
'staring' placed around 'l' is 'STARLING'.
Can you help me to learn more?
(Other definitions for starling that I've seen before include "Passerine bird" , "goes around the pier" , "Gregarious bird" , "Common songbird" , "Gregarious songbird" .)