Whenever I arrive at a new spot, my instinct is to look around for signs. I’m curious to know the local rules, the species I might see, and any unique features of the area. I assumed this was common—that most people also stopped to read signs before heading out. But that assumption got flipped on its head when I started digging into how effective marine protected area (MPA) signage really is. 

Over a decade ago, California led the nation to become the first network of marine protected areas (MPAs) in the United States. When the...