Poorly Managed Trails Can Permanently Damage Ecosystems, Experts Warn

Every footstep on a trail leaves a mark. Most of the time you cannot see it. But it is there.

On the first Saturday of June each year, the World Trails Network marks International Trails Day to celebrate the paths that connect people to wild places, to champion conservation, and to honor the work of those who maintain them. This year, as experts gathered to discuss the value of trails, a troubling pattern emerged: the very infrastructure designed to protect nature can destroy it permanently if built and managed without care.

The Atlantic Forest stretches across northeastern Argentina, Paraguay, and southeastern Brazil. It is a place of towering trees, dense undergrowth, lianas, and an abundance of life—mammals, birds, reptiles, amphibians. Only about 24 percent of its original forest cover remains today, fragmented into protected reserves and private holdings. Trails through these remnants allow visitors to witness centuries-old trees, over 320 bird species, more than 300 butterfly species, orchids, and thousands of other forms of life. But the forest is under siege from logging, agricultural expansion, and urban sprawl. The trails themselves, if poorly designed, can accelerate its decline.

Julián Baigorria, a biologist and coordinator at Karadya Natural Reserve, part of the Félix de Azara Foundation's private reserve program, explained to journalists that trail design is essential. At his reserve, visitors walk through primary forest—woodland that has never been completely cleared—where some trees exceed 400 years old. The reserve also maintains restoration plots and agroecological farms growing shade-grown yerba mate. The trails make all of this visible and comprehensible. But visibility alone is not enough.

Valeria Ojeda, a conservation biologist and ecological literacy researcher at INIBIOMA in Bariloche, Argentina, stressed that wildlife viewing should happen in small groups to minimize noise and impact. She called for stronger legal frameworks across Latin America, backed by adequate funding, to ensure trails protect both ecosystems and the educational experience of visitors. "This is not only a government responsibility," she said. "The private tourism sector must be held accountable as well."

The real problem runs deeper than individual behavior. Researchers from the University of Lleida in Spain and the Federal Institute of Education, Science and Technology of Amazonas in Brazil analyzed 28 studies on trail management in protected areas worldwide—work from the United States, Australia, Japan, China, Poland, South Africa, Belgium, Canada, and Costa Rica. They published their findings in Environmental Management and discovered a fundamental source of damage: scientists, managers, and lawmakers use the same words to mean different things.

When a technical report confuses "restore" with "rehabilitate" or "recover," the consequences can be irreversible. To restore a trail means to actively intervene so the entire ecosystem—plants, animals, soil—returns to its state before the trail existed. This happens when a trail is closed permanently. To rehabilitate means to repair the trail so it functions safely again, without necessarily recovering all the biodiversity that once lived there. A manager who rehabilitates when restoration is needed leaves a damaged ecosystem with no path back to health.

The researchers created a decision-making diagram—like a flowchart in a video game—to guide park and reserve managers through concrete questions: Does a trail already exist here? Is it still necessary? Is it damaged or destroyed? The answers point to the correct intervention and its proper name. They also developed a model linking the severity of trail damage to an ecosystem's resilience—its ability to heal itself without human help. Beyond a certain threshold, an ecosystem loses that capacity entirely. The study identified four levels of trail-related damage: impacted, damaged, degraded, and destroyed. Each requires a different response.

Baigorria offered practical guidance: before building a trail, consider the terrain, distance, width, and what activities will be allowed. Ensure visitors can see, hear, and smell the forest while walking safely on a well-marked path. Pablo Grilli, coordinator of the Grasslands Program at Aves Argentinas, a conservation organization, described a trail as an invitation to enter a place from within—to step from outside the forest, the wetland, the mountain, and cross the threshold into it. When we are children, we learn to be respectful, to break nothing, to listen to guides. That same discipline applies in a national park or reserve. If everyone carries that responsibility, every natural space can be experienced fully: its colors, sounds, smells, humidity, heat, landscapes, and the beings that inhabit them.