Sea captain's birds leaving rents or small holes (7)
I believe the answer is:
eyelets
'small holes' is the definition.
(I've seen this in another clue)
'sea captain's birds leaving rents' is the wordplay.
I cannot quite see how this works, but
'rents' could be 'lets' (I've seen this in another clue) and 'lets' is found within the answer.
The remaining letters 'eye' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'or' acts as a link.
Can you help me to learn more?
(Other definitions for eyelets that I've seen before include "peep-holes" , "Rings for reinforcement" , "Small holes" .)