Oops, it doesn't look like 'seabass day' is a national day..

Other days

prosecco

Prosecco Day
cuddle up

Cuddle Up Day
blanket fort

Blanket Fort Day
boba

Boba Day
ruby

Ruby Day
boyfriend

Boyfriend Day
donate your hair

Donate Your Hair Day
kale

Kale Day
bow tie

Bow Tie Day
camera

Camera Day