An animal shelter in a Yemen port (4)
I believe the answer is:
aden
'a yemen port' is the definition.
(I've seen this before)
'an animal shelter' is the wordplay.
'an' becomes 'a'.
'animal shelter' becomes 'den' (I've seen this in another clue).
'a'+'den'='ADEN'
'in' acts as a link.
(Other definitions for aden that I've seen before include "Red Sea port" , "Dane in seaport of Yemen" , "Dean out in the seaport city" , "Commercial capital of Yemen" , "Yemen's chief port" .)