Veteran Ecologist Daniel Janzen Leads Decades‑Long Forest Restoration in Costa Rica

In northwestern Costa Rica, the return of forest cover has been a slow, layered process that began with removing cattle, extinguishing fires, and managing invasive grasses that made former ranchlands highly flammable. Daniel Hunt Janzen, now 87, has spent more than half a century working alongside his wife, Winnie Hallwachs, to turn a conservation idea into a functioning landscape. Their efforts are supported by park leaders, field staff, parataxonomists, teachers, donors, government ministers, neighbors, and families who maintain the area after the initial funding and attention fade. Janzen has stepped back from university teaching to serve as Chief Scientist of the Guanacaste Dry Forest Conservation Fund (GDFCF), the nonprofit he and Hallwachs founded to coordinate this long‑term restoration. The project illustrates that restoring a forest requires science, sustained funding, political agreements, community trust, and daily maintenance—far more than a single charismatic figure can achieve.