Japan’s population is declining, especially in rural areas. Although fewer people might be expected to give wildlife room to rebound, wildlife is also disappearing where farms have been abandoned. Researchers say small farms in Japan’s foothills create a mosaic of rice paddies, open pastures and scattered woodlands that provides habitat for many kinds of wildlife.
Traditional land tending can help maintain these habitats: cutting trees for firewood and gathering leaves for fertilizer made room for orchids and azaleas, while rice paddies provided habitat for rice fish and heike fireflies. Scientists say many species found on farms have evolved alongside humans.
A 2025 study from Japan found biodiversity was stable only where the human population was also stable. In areas with declining populations, researchers recorded decreases in the abundance of butterflies, fireflies, frogs, birds and native plants.
Similar rural depopulation is occurring in countries including Spain and China as people move to cities for work. The loss of human tending can harm species dependent on landscapes shaped by people. A study of the Lake Constance region in the European Alps found plant diversity peaked in the medieval era, when small farms created a patchwork of fields, pastures and forests. Diversity was greater then than in the earlier closed forests or the later industrial farms.
Adam Spitzig, lead author of the Lake Constance study and a PhD candidate at Stanford University, said conservation need not choose simply between farming and biodiversity: small, diversified farms can sustain biodiversity while supporting food production.