BUR #3714 has been approved by @evazion.
remove implication shark_tail -> tail
create implication shark_tail -> fish_tail
If someone is searching for fish tails I doubt they're thinking "I only want fish tails that aren't sharks".
(Though to be honest a lot of these are only tagged as shark tails because the character is canonically a shark, so we might want to consider an alias too)
EDIT: The bulk update request #3714 (forum #174591) has been approved by @evazion.
Updated by DanbooruBot