[Mockup] The Science of Marine Reserves

Oceans around the world are becoming degraded. Evidence shows that human activities are altering ocean ecosystems beyond their natural range of variability. According to numerous scientific studies, fish, shellfish, and other species are declining in many places. The changes are impairing the ocean’s capacity to pro vide food, protect livelihoods, maintain water quality, and recover from environmental stress. These and other benefits, collectively called ecosystem services, depend on healthy ecosystems.

Many people are inquiring about solutions to reduce negative impacts and foster ocean health and resilience. Increasingly, government agencies, commercial groups, non-government organizations, the public, and scientists are discussing the idea of establishing marine reserves to complement other efforts to restore and sustain ocean ecosystems.

Marine reserves are defined as ocean areas that are fully protected from activities that remove animals and plants or alter habitats, except as needed for scientific monitoring. Examples of prohibited activities are fishing, aquaculture, dredging, and mining; activities such as swimming, boating, and scuba diving are usually allowed. Marine reserves receive permanent protection, rather than seasonal or short-term protection. Because marine reserves protect habitats and the diversity of animals and plants that live in those habitats, marine reserves are a form of ecosystem protection that produces different outcomes from other management tools. As with any form of management, a marine reserve is only effective if its protection is enforced.

Many other kinds of marine protected areas (MPAs) exist. However, they exclude only some human activities that harm animals, plants, and habitats. Those MPAs may provide some benefits, but they do not produce the same outcomes as marine reserves because they do not provide the same comprehensive level of protection.

Although marine reserves can be an effective tool, reserves alone cannot address problems such as pollution, climate change, or overfishing. Other management strategies are needed along with the creation of marine reserves.

This website summarizes the latest scientific information about marine reserves, including case studies from the United States. Scientific evidence shows that marine reserves usually boost the abundance, diversity, and size of marine species living within their borders. Science can explain how these changes occur and provide useful information for designing marine reserves.