Beyond the blue label:
the BUFFER story
How a practical classification helped change the way marine protected areas are understood and assessed
A protected area under pressure
Each summer, activity rises sharply in the Cerbère-Banyuls marine reserve on France’s Mediterranean coast. Fishing, diving and boating intensify across a reserve that combines a small fully protected zone with a much larger area where different uses continue under regulation.
For three years, BUFFER researchers monitored fish communities before and after this seasonal surge. They wanted to know whether the reserve’s zoning could absorb the recurring pressure and allow the ecosystem to recover before the following summer. They observed that, after the busiest months, fish communities in the partially protected area became more similar to those outside the reserve. By the next season, however, they had shifted back towards the condition observed near the fully protected zone. The combination of strict and partial protection appeared able to buffer a recurring increase in pressure.
The case pointed to a much wider problem. The term “marine protected area” describes a designation, but says little about what people can actually do within its boundaries. Designation alone was not enough.
The Cerbère-Banyuls marine reserve on France’s Mediterranean coast combines a small fully protected core with a larger partially protected zone where fishing and other activities continue under restrictions. BUFFER monitored fish communities within these zones and outside the reserve to examine their response to recurring summer pressure.
Photo: Luc Viatour. Map adapted from Kayal et al. (2020).
What counts as protection?
As countries expanded their marine protected-area networks, the area designated became an obvious way to measure progress. But equal areas on a map could represent very different realities. One might prohibit extraction, while another continued to allow several kinds of fishing, aquaculture or seabed exploitation. BUFFER set out to make those differences visible.
The project compiled detailed information on the activities and regulations of 54 marine protected areas and 115 individual zones. Managers helped supply information that was often absent from global databases, including which activities were allowed, how they were regulated and what measures were in place to reduce their impacts.
BUFFER used this evidence to create a classification based on regulations rather than stated objectives. Areas were placed along a spectrum from fully protected to effectively unprotected, according to the extractive and potentially damaging activities permitted within them.
“We have observed that the stricter the protection, the greater the benefits to the ecosystem”, explains BUFFER coordinator Joachim Claudet. Highly regulated partially protected areas supported greater abundance and biomass of targeted fish than unprotected areas. Moderately regulated areas also showed benefits, particularly when adjacent to a fully protected zone, while weakly regulated areas showed no comparable effect.
Age, size and the capacity to implement regulations also influenced the results. Older and larger protected areas tended to perform better, as did those with a stronger capacity to enforce their regulations.
What makes partial protection effective? Older and larger highly or moderately regulated areas tended to support greater abundance and biomass of targeted fish, while weakly regulated areas showed little benefit. Partial protection also tended to perform better when adjacent to a fully protected zone, especially in moderately regulated areas.
Adapted from Zupan et al. (2018).
From evidence to a usable method
BUFFER combined this global analysis with field monitoring, fishing experiments, interviews and governance studies in individual protected areas. Managers supplied regulatory information that was often missing from global databases and helped shape fieldwork. Fishers’ organisations facilitated contact with people whose activities and livelihoods were directly affected by protection measures.
The classification complemented systems based on management objectives by adding another question: what ecological effects could reasonably be expected from the rules in force? A step-by-step decision tree, followed by the online ClassifyMPAs tool, allowed managers and conservation organisations to classify their own sites and explore how changes in regulations or zoning would affect their classification and expected protection level.
BUFFER used acoustic tagging to examine how fish behaviour affects the protection provided by marine reserves. The photograph shows a sea trout being tagged during project fieldwork, while the figure presents a separate analysis of Atlantic cod. Some cod remained almost entirely within the no-fishing area, whereas others regularly crossed its boundaries. These differences can affect survival and spillover into surrounding fishing grounds, raising the possibility that reserves may favour less mobile fish over time.
Photo: Carla Freitas. Figure reproduced from Villegas-Ríos et al. (2016).
From project tool to global framework
The approach first gained ground among practitioners, with MedPAN, the network of marine protected-area managers in the Mediterranean, and the international Blue Parks initiative adopting the classification and its protection criteria.
BUFFER’s regulation-based classification later helped inform the MPA Guide’s assessment of protection levels. Introduced in 2021, the Guide evaluates marine protected areas according to their stage of establishment, level of protection, enabling conditions and expected outcomes. MPAtlas, a global platform for tracking marine protection, now applies both the MPA Guide and the regulation-based classification developed through BUFFER. Instead of treating all designated areas as equivalent, it reports their stage of establishment and level of protection and links these to expected conservation outcomes.
What began as a way to compare individual protected areas was now helping to inform regional assessments and global tracking.
MPAtlas allows marine protected areas to be explored according to their stage of establishment and protection level. The map shows the MPA Guide protection-level layer, helping reveal differences that are hidden when progress is measured only through total designated area.
Source: MPAtlas (accessed in July 2026).
Beyond the label
BUFFER began with a deceptively simple question: what does it mean for an area of sea to be protected? Its answer went beyond a new set of categories. By linking regulations with expected ecological outcomes, the project gave managers and conservation organisations a clearer way to distinguish intention from implementation.
A protected designation may state what an area is meant to achieve. The activities allowed, the strength of its rules and the capacity to enforce them determine what that protection is likely to deliver.
Not all marine protected areas offer the same protection. BUFFER’s classification distinguishes areas according to the extractive activities permitted and their likely ecological effects, from fully protected to unprotected. The underwater scenes illustrate expected benefits rather than predicting the condition of every site: outcomes also depend on factors such as age, size and the capacity to implement and enforce regulations.
In brief
- Marine protected areas (MPAs) can range from no-take reserves to zones where fishing and other activities continue under varying restrictions. Yet they are often grouped together under the same label, concealing major differences in the protection they provide.
- BUFFER developed a classification based on what activities were actually permitted and their likely effects on marine ecosystems. It then tested how different levels of regulation influenced fish populations and whether partially protected areas could recover between recurring periods of human pressure.
- The approach was taken up by marine managers and international initiatives, and later helped shape frameworks now used to assess the quality, rather than simply the extent, of marine protection.
Explore more impact stories
This summer, Biodiversa+ looks back at research projects supported through its predecessor, BiodivERsA, exploring how scientific collaboration has contributed to policy, practice and innovation. Each story highlights what changed, how researchers worked with stakeholders, and what future projects can learn from their experience.
