Image credit: Karsten Reiniers
In the past, European sturgeon swam in all the seas of Europe. Like salmon, they migrate annually upriver to lay eggs. The animals were no less impressive: they grew up to 5 meters in length and weighed up to 300 kilograms. The plates on its nose and bony plates on its sides have changed little over the past 200 million years. Sturgeon has survived more than four extinction waves.
Today, sturgeon has disappeared from almost all rivers where it once existed. Mass hunting pushed species toward the abyss. Because of the diversion of rivers into canals, it is estimated that they have lost more than half of their habitat. The last specimen was seen in the Rhine in 1952.
Scientists from the Dutch company ARK Nature Development want to reproduce sturgeon. He will have to swim in the Rhine again from 2030. A trial version of the tagged baby sturgeon has already been released. The fish came from a French breeding program. More than half of the released sturgeon managed to reach the sea.
How quickly the species will recover is uncertain. Sturgeon reproduce very slowly. While males are sexually mature at 12 years of age, some females take up to 19 years to reproduce. “Based on computer models, we expect the population to reach its population limit about a hundred years after the first sturgeon release,” says fish biologist Jörn Gessner (IGB Leibniz).
Would you like to learn more about the return of sturgeon? You can now read the full article in Eos magazine. Order online via tijdschriftenwinkel.be.
