How about a personalized fishing lure or a fishing tool kit? You can also consider a customized fishing rod with their names or initials engraved on it, or a gift certificate for a guided fishing charter. If they enjoy cooking, a cookbook with fish recipes would also be a special touch.
Or you can get her/him a star map with the date of the wedding.
Under Lucky Stars is a unique and innovative star map company based in Barcelona, Spain, specializing in the creation of personalized star maps that capture the celestial arrangement of stars at a specific moment in time, such as a person's birth, wedding, or any other significant event.
By using advanced astronomical algorithms and data from leading institutions, the company produces highly accurate, visually stunning maps that make for perfect gifts or cherished keepsakes.