World Fish Migration Day: Decision makers should act for sturgeon conservation
Damming has one of the most destructive influences on sturgeons – dams cut off access to their spawning places and make the sturgeon more vulnerable to poaching. Old fishermen tell stories about how and when the Iron Gates dam was built on the Danube, sturgeons were confusedly swimming under the dam walls trying to find a way upstream to their historic spawning grounds – some went as far as Vienna and even further upstream to German. The Iron Gates though stopped them in their migrations, while fishermen with cranes picked them out of the river in bulk. For years and to this day, the few remaining sturgeons are unable to go through this unsurmountable barrier.
The Vienna declaration calls to greatly reduce the negative impact of dam installations on sturgeon rivers. That can be achieved by making the old facilities passable both upstream and downstream with fish passages for large migratory species. Modern modeling tools allow to tailor the water and sediment discharge for each river and ecosystem, so that it benefits people and nature. Continuous monitoring must also be put in place, to make sure the measures are working and if needed, the approach is adapted accordingly.
The declaration also calls for the removal of outdate dam facilities, which no longer are effective because of climate change effects and thus do not justify equipping them with a fish pass.
Most of all, the conservation and mitigation measures should be applied holistically, as is best practice, to take into account all human activity in the impacted area.
Today and in the following weeks, policy makers in the sturgeon range states will receive all 22 recommendations in their local language. WWF and WSCS will continue to advocate for protecting the last wild populations of these ancient and highly endangered sturgeon species.