Pile up tins for fish-eaters (8)
I believe the answer is:
pelicans
'fish-eaters' is the definition.
'pile up tins' is the wordplay.
'up' indicates an anagram (letters get chucked up).
'tins' becomes 'cans' ('can' can be a synonym of 'tin').
'pile' is an anagram of 'peli'.
'peli'+'cans'='PELICANS'
'for' acts as a link.
(Other definitions for pelicans that I've seen before include "Large-billed birds" , "Seabirds with large bills and pouches" .)