Iran’s ancient Hyrcanian forests on fire | Science

The Hyrcanian forests, located along the southern coast of the Caspian Sea, represent one of the most valuable relict temperate ecosystems in the world (1). Listed as a World Heritage Site by the United Nations Educational, Scientific and Cultural Organization (UNESCO) in 2019, this 1.85 million ha ecosystem is home to more than 3,200 species of plants, 180 species of birds and dozens of species of mammals (2). After surviving for more than 25 million years, forests have lost more than half their original area since the 1950s, primarily due to land use change toward agriculture and urban development (3, 4). In November 2025, late and inadequate firefighting efforts allowed a wildfire to destroy an additional 600 ha of forest (5, 6).