Novel operational index reveals rapid recovery of genetic connectivity in freshwater fish species after riverine restoration

Hyperfragmentation of rivers by anthropogenic barriers is a major threat to biodiversity. Restoration policies are being adopted worldwide mitigate these impacts, particularly those on fish connectivity. We assessed the utility novel genetic index fragmentation, FINDEX, monitoring real-time responses two genera restoration operations at 11 weirs in France. The FINDEX outperformed traditional tools, detecting more efficiently, and thereby improving estimates recovery connectivity following restoration. Most had significant impacts before restoration, especially highest steepest ones. actions systematically improved connectivity, sometimes completely just few months, with an overall halving fragmentation levels. Our study demonstrates that current recovering practitioners may benefit from as new operational tool assess barrier strength for nonmigratory organisms plan monitor riverine