Happy World Ocean Day 2026!  

This year, the official action theme of World Ocean Day is “Strong Marine Protected Areas for Our Blue Planet.”  But what is a Marine Protected Area—and what makes a strong one?   

There are many ways people have conserved and managed the ocean. Spatial management, or protecting specific parts of the ocean by creating zones with different rules for use, could feel strange. Above the water, the sea looks like a uniform blue liquid as far as the eye can see. How does one create plots of water or draw lines on the water, or know when a certain line is crossed? 

However, protecting parts of the ocean has been practiced since time immemorial by different indigenous and coastal communities. From Indigenous communities in the Pacific Northwest to Aboriginal communities in Australia, communities have long depended on the sea and have practiced forms of ocean stewardship for generations. People who rely on and manage their marine resources can see what is invisible to outside observers—that the distribution of fish and other resources is not random but is a complex interplay between habitat, oceanographic conditions, food availability, and other environmental factors. Through time, different communities have understood that fish are associated with particular places and seasons. Modern Marine Protected Areas (MPAs) share some similarities with these long-standing forms of marine stewardship, though traditional management systems are often more diverse than what is typically categorized as an MPA.

MPAs could have different conservation targets within their area (e.g., protecting certain types of fish or habitats or entire ecosystems) and levels of protection, ranging from complete no-take zones to areas where multiple uses are permitted.

With the global target of 30×30 (protecting 30% of the world’s oceans by 2030), the pressure to designate MPAs rapidly has intensified. Researchers and environmental advocates worry that areas are created focusing on quantity over quality. Whether or not MPAs work depends on whether the protected area is in the right place and large enough to protect what it targets (amongst other things). This matters because not all MPAs are created equal in either design or effect. For example, creating a protected area to conserve fish in a place with no fish habitat would not be effective. Further, MPAs work better to conserve fish that have a smaller habitat range. Migratory species would benefit less from a small area being protected when they can cross entire ocean basins. Protecting reef fish in coral habitats may work well with smaller protected areas, while migratory tuna or sharks may spend most of their lives outside protected boundaries.

But sometimes, MPAs displace fishing effort from inside the area to the areas surrounding it, concentrating fishing pressure on surrounding areas and causing a net decline in resources. Habitat degradation outside of MPAs can also negatively impact the broader ecosystem. Sometimes, MPAs could even displace traditional coastal communities or forbid them from accessing certain areas. Combined with the increasing number of paper parks (MPAs that are legally designated but not enforced), it is unsurprising that a lot of MPAs receive criticisms and inevitably fail to produce any conservation benefits.  

Instead of using the global target of 30% MPAs as a static goal to tick off by 2030, governments and NGOs need to utilize such global commitments as momentum to reexamine what we are protecting and how. MPAs cannot solve everything, and without the fundamentals, such as robust ocean data and science combined with traditional ecological knowledge, we cannot even begin to design an appropriate MPA. A strong MPA is not just a line on a map. It is a living system — ecologically grounded, community-informed, and actively enforced. As for the fish beneath the surface, the line only matters if someone is watching and if it was drawn in the right place to begin with.

Elle Wibisono is the Technical Director of the Blue Lab at Georgetown SFS Asia-Pacific. A fishery scientist and science communicator, she has worked across international NGOs, government, and coastal communities — bringing together perspectives on how people and the ocean shape each other. Elle is the author of A Snapper Tale, a children's book on the surprising diversity of red-colored snappers, and occasionally publishes fish comics at @fishtory.co. Her current work sits at the intersection of art, science, and policy — finding ways to create real impact for communities and nature.