Fig. 3: Relationships between river barrier density and fish species richness across migration and threatened categories in the Mekong Basin.

Bivariate choropleth plots showing the relationship between barrier density and potamodromous species richness (ranged from 0–135 species; a, diadromous migrant fish species richness (ranged from 0–125 species; b threatened fish species richness (IUCN status: Vulnerable (low threat), Endangered (moderate threat), and Critically Endangered (highest threat) c, in each sub-basin of the Mekong River.