Does River Fragmentation By Dams Increase Fish Extinction Rates?

Human activities are often linked to contemporary species extinctions. For riverine fishes, a highly studied and emblematic taxon, introduction of non-native species, damming of rivers, increasing water pollution and sediment loads, eutrophication, habitat degradation and water abstraction for human and agricultural consumption are believed to be among the greatest abiotic threats worldwide. Focusing on Western Europe and North America, two strongly impacted regions, we quantify fish species loss per river basin and evaluate for the first time to what extent, if any, these threats predict spatial patterns of freshwater fish extinctions.