A doubling of fish biomass along Asia’s longest river shows hope for large-scale conservation efforts and a lifeline for the endangered finless porpoise.

“The biggest take home is let’s do a better job of managing our freshwater rivers so we never have to consider full fishing bans as the medicine,” said Cooke. “Although this seems to have been effective here, the collateral damage to fishing communities is immense.”

Now entering its sixth year, the ban is not a permanent fix nor a cure to all ecological issues. Yet the doubling of biomass is a historic milestone.