One of my family’s favorite beach-type pass times is shelling. We hit the beach and drag great gobs of different shells back to the vacation rental - only to be forced to leave 90% behind because we cant pack them all - or they smell funny.
I did find out you can clean seashells so they don’t smell - but picking up “dead shells” is your best bet for this, although that doesn’t guarantee they’ll be ’stink free’.