About a tenth of the ocean is now officially protected.
In more than half of Europe's protected areas, the trawlers never stopped.
Introduction
Marine protected areas (MPAs) are areas of the ocean with limits on human activity in order to protect biodiversity and maintain healthy marine ecosystems. MPAs go by a lot of names, including marine parks, marine reserves, marine sanctuaries, and no-take zones. As of August 2026, 9,8% of the ocean is protected by MPAs. Only 3,5% of the ocean is fully or highly protected, however. The MPA guide categorizes based on protection level and stage of establishment, as shown in the figure below.
The MPA guide covers protection level and establishment stage. It takes both to protect an area.
Many types of MPAs exist with very different goals and levels of protection. The strictest variety allows no humans at all, but these are usually small and rare. Other MPAs allow only recreational use, such as traveling through the area or snorkeling, for example. Others allow some fishing, and some might be divided into zones with different rules. The number of MPAs is rising quickly, but their effect is under debate. Illegal harvesting, lax rules/regulations, and cetaceans leaving the area because it is too small are all complicating factors that reduce their effectiveness. A study by Graham J. Edgar, published in Nature, examined 87 MPAs worldwide and identified five keys to their effectiveness. The five traits are: no-take, well enforced, older than 10 years, large (more than 100 square km), and isolated by either deep water or sand. They are also called the “NEOLI” features (No-take, Enforced, Old, Large, Isolated). The effective MPAs had five times more large fish biomass and 14 times more shark biomass than fished areas. 59% of the studied MPAs, however, had only one or two of the five traits, which made them indistinguishable from fished sites.
MPAs are thus a promising conservation tool, but their design and management vary greatly, and so do the effects.
Paper parks
MPAs are a critical tool in the protection of the marine environment. MPAs are rapidly increasing as it has become known how bad a condition much of the ocean is in. Efforts to create larger and more numerous MPAs have been a top priority for the past decade. Driven partly by global targets such as the goal of conserving at least 10% of coastal and marine areas by 2020, as was agreed under the United Nations Convention on Biological Diversity. Almost 200 countries have agreed to protect at least 30% of the ocean by 2030. These goals have led to many more MPAs, but the actual effectiveness is somewhat forgotten. The designation of an MPA does not change much itself. It must be supported by management, or else they become “paper parks”.
In Europe, MPAs now cover 29% of territorial waters. A study by Manuel Dureuil examined industrial trawl fishing and sensitive indicator species in 727 MPAs in Europe. It turns out that 59% of these MPAs are commercially trawled, and the average trawling intensity in these MPAs is at least 1.4 times higher than in nonprotected areas. In heavily trawled areas, the abundance of sensitive species, such as sharks, rays and skates, decreased by 69%. European MPAs are failing to protect the marine environment not because of a lack of MPAs, but because of their poor quality.
Protection for cetaceans
Historically, the protection of marine animals and systems has resembled that of terrestrial systems. MPAs are an example of this. Place-based conservation, like MPAs, can be very effective and is an important tool to protect cetaceans with relatively constant habitats. In this case, the protection of critical habitats and the pathways between them offers the necessary protection. The vaquita and Hector’s dolphin are examples of cetaceans with restricted ranges where MPAs should be very valuable. The conservation of species such as the humpback whale, right whale, and grey whale, which all travel long distances seasonally, is harder to define. In this case, it is almost impossible to cover their entire range. This poses the dilemma of whether to protect at very large scales or to protect smaller networks of protected areas. It also requires cooperation between countries since the animals cross national borders and protection across oceans is difficult to achieve. The good news is that cetaceans are not equally vulnerable in all areas of their travel. So if it is possible to protect the most vulnerable areas of their journey, you can achieve substantial protection through MPAs.
BBNJ
Until recently, many MPAs have been concentrated in national waters. This leaves a big hole in the protection of marine animals in large parts of the ocean. Many whales migrate across both national and international jurisdictions in their seasonal journeys. A big step towards solving this took effect on January 17, 2026, with the agreement known as the Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction (BBNJ) or simply the High Seas Treaty. This agreement establishes a legal framework to better conserve the marine environment beyond national jurisdiction. The high seas are international waters and cover around two-thirds of the global ocean, house an estimated 10 million species, and account for an estimated 95% of the ocean’s volume. Only about 1% are currently protection or conservation zones.
The high seas are vital to cetaceans, but have been hard to regulate due to, among other things, fragmented governance. In September 2025, the treaty got the necessary 60 country ratifications and was thus ready to take effect in 2026. The treaty allows the creation of MPAs in international waters and requires environmental impact assessments. It also promotes technology transfer, which should aid developing countries in participating in ocean research and conservation.
Sperm whales are remarkable animals with intricate language and tight-knit social structures. They are also very important to the marine ecosystem of Dominica. Around 200 sperm whales use Dominica’s west coast as feeding and nursing grounds. In a groundbreaking initiative, Dominica has created the world’s first Sperm Whale Reserve. The reserve takes up less than three percent of Dominica’s waters, but helps a lot in protecting the sperm whales. Restricting ship traffic to specific corridors lessens the risk of ship strikes and lowers noise pollution. Another important feature of the reserve is that it combines marine conservation with economic growth. Through a respectful and regulated whale tourism operation, the economic gains can offset the costs of the reserve.
It is a great example of how well-designed conservation can benefit all.