A gull took a bride’s dress! (7)
I believe the answer is:
seabird
'a gull' is the definition.
'a bride's dress' is the wordplay.
'dress' indicates anagramming the letters (prepare).
'a'+'brides'='abrides'
'abrides' with letters rearranged gives 'SEABIRD'.
'took' is the link.
This may not be right. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for seabird that I've seen before include "Gannet possibly" , "Gull perhaps" , "A gull, for instance" , "Marine creature" , "Gull, for example" .)