Evidence Matters: What Nosara’s New Construction Regulations Mean for the Refuge

July 2026. By Dr. Vanessa Bézy

This month, Nosara secured landmark construction regulations for the Ostional National Wildlife Refuge and surrounding area. From my perspective as a scientist, moments like this are exactly why evidence matters.

These kinds of legal and bureaucratic processes are long, expensive, and difficult. In this case, the process took more than six years and was intended as a temporary measure until a broader regulatory plan could be put in place. Six years later, those permanent regulations still are not in place, and there is no clear timeline for when they will be. In a place growing as quickly as Nosara, that delay matters. If the population doubles in a few years, we can lose an enormous amount before the proper protections ever arrive.

I think the underlying questions from the beginning were simple: Is there something worth protecting here? And is there a problem serious enough to require action?

For many people in this community, the answer to both questions was always yes. But for governments, courts, and institutions, concern alone is usually not enough. They are not on the ground witnessing these impacts every day, and without clear evidence, the problem can remain abstract or easy to underestimate. In order to grasp the problem, they need evidence and numbers. They need to quantify what is at stake and what the risks are.

When you say this is an ecologically important area and that tourism and development are growing rapidly, that tells one story. But when you say this is a globally important site for olive ridley sea turtles, in one of the most biodiverse regions in the world, in a country whose economy and identity are deeply tied to ecotourism and environmental protection, in a district whose population has grown dramatically while water pollution and the loss and fragmentation of habitat are already serious issues, that becomes a much stronger statement.

And when you can go even further — when you can show that wildcats are still using habitat in and around developed areas, that sea turtles are still nesting on our beaches— then you are no longer talking about a vague idea of nature. You are talking about an existing, functioning, still-thriving biosphere that is under pressure and urgently needs protection. And, most importantly, a community that recognizes that value and depends on it for their livelihoods.

That is why evidence matters in moments like this. At the end of the day, governments need numbers in their reports. They need something concrete they can defend. Historically, it has been difficult to quantify the intrinsic value of nature, even when communities feel it deeply. Science helps close that gap. It allows us to show, with evidence, not only that an area is beautiful or special, but that it supports biodiversity, public health, local livelihoods, and long-term community wellbeing. 

This decision is monumental because it shows what can happen when that evidence is framed clearly and used well. It puts the local environment and community first, and in many ways it reflects what has always made Ostional and Nosara unique. From its founding, this protected area has been tied to a participatory community process. That is very different from the more common model of creating a protected area by drawing a line and pushing people out. Here, the idea has always been that conservation and community have to work together.

To me, this decision says something important about the relationship between data, development, and protecting the refuge. Development on its own is not the problem. The real challenge is understanding its impacts and making sure growth is guided in a way that reduces harm and allows people and wildlife to coexist responsibly. Without data, it is easy to argue for more construction, more density, and more growth because the risks remain abstract. But once the facts are clear—once the evidence shows that there is something important to protect and that there are already real threats to it—the government has a responsibility to act.

This is especially true in Costa Rica, where environmental protection is strong in law, even if implementation is often imperfect. It is much easier for overdevelopment to continue when there are no hard facts suggesting that an area is ecologically significant or already at risk. But once those facts are on the table, it becomes much harder to justify inaction.

WCA's role in this process was to contribute scientific evidence, especially around water and light pollution. Both issues are critical.

Wastewater treatment is included in the regulations because studies have shown that in much of this area, relying on simple septic systems is not effective. If we continue to grow without adequately treating wastewater, that contamination will reach groundwater, rivers, and eventually the ocean. That is a public health risk, a marine ecosystem risk, and an economic risk for a community that depends heavily on tourism and recreation linked to clean water.

One of the biggest realities we encountered is that the challenge is not only financial. In many cases, there also simply is not enough space. Proper wastewater treatment takes room, and that is one reason the new rules limit how much of a lot can be built on. Reducing building coverage helps ensure there is enough space for wastewater infrastructure while also preserving vegetation and infiltration.

That 50% cap matters for other reasons too.

The more of a property that is covered by construction, the more fragmented local habitat becomes. Instead of connected green space, you end up with isolated ecological islands. Tree cover and vegetation help increase infiltration, support groundwater recharge, reduce erosion, and reduce flooding. When lots are continuously subdivided and heavily built without broader planning, those functions begin to disappear.

Height limits matter as well.

Keeping buildings lower helps reduce fragmentation of the tree canopy and can also reduce light pollution by keeping rooflines below the treeline. That matters because light pollution is not just an aesthetic issue. It can disorient nesting turtles and hatchlings, disrupt other nocturnal wildlife, and affect people too. These limits help maintain darker, more connected habitat while reducing one of the most preventable pressures on the refuge.

For property owners, these regulations mean that if you own land or plan to build in the buffer zone, the rules are clear. New construction must include an appropriate wastewater treatment system. Building coverage is capped at 50% of the lot. Height limits apply depending on distance from the refuge. And lighting and windows must be managed to reduce impacts on wildlife.

Some people are frustrated by these restrictions. I understand that. But these rules exist for a reason. They are not arbitrary. They reflect the ecological limits of the landscape and the reality that development without proper infrastructure has consequences. If these regulations are not respected, the consequences will not only be environmental. Over time, they will also affect the health, quality of life, and economic wellbeing of the communities that depend on this landscape.

What gives me hope is that this decision shows the environment is not invisible. It shows that science, community concern, and legal action together can still shape the future. And it reinforces something I believe strongly: in order to protect wildlife, we must also protect the needs of the communities that depend on it.

If we want Nosara to remain the extraordinary place that it is, we cannot wait until the damage is obvious and irreversible. We have to act while the ecosystem is still functioning, while wildlife is still using habitat, while turtles are still nesting, and while the community is still willing to fight for that future.

That is what evidence allows us to do. It helps us move from feeling helpless to making a case that cannot be ignored.