The Scientific Return of Biodiversity Conservation: Evidence from Fishing Bans Along the Yangtze River

We document arguably unintended returns of biodiversity conservation to science discovery, exploiting the 2002 fishing ban in China—an ecosystem restoration policy without explicit science-related objectives, which allows us to implement a difference-in-differences design across fish species. We find that the ban substantially increased research on affected species: funded programs rose by 21.5%, total funding by 22.8%, publications per program by 97.0%, and citations per paper by 106.7%. The effect is concentrated among researchers with geographic access to the river, and is stronger for non-extinct species and non-farmed fish species, suggesting that conservation expanded the supply of biological materials available for research. The ban also increased related public influence and patents. These results reveal that biodiversity conservation generates a significant scientific dividend through the restoration of natural research inputs, with implications for evaluating the broader benefits of ecosystem protections in an underdiscussed dimension for the science of science.