For the first time in several decades, an adult allis shad has been sighted in the Sieg in the Rhein-Sieg district.
An automatic fish counter at one of the control stations near Sankt Augustin (Rhein-Sieg district) made the « sensational recording » the Foundation for Water Protection and Migratory Fish NRW announced on Tuesday.
Allis shad have been considered extinct in the Rhine system for a good 60 years, but have been reintroduced for a few years. The sighting shows that the stock of fish in the Rhine is growing steadily, said Andreas Schubert, head of the reintroduction project at the Rhenish Fisheries Association.
Tiny allis shad larvae bred in France have been released into the Sieg and other Rhine tributaries for years. The other Rhine bordering countries and federal states are involved in the project.
The animals migrate to the oceans and return – like the specimen just seen – to their « home waters » after a few years when they are mature and up to 70 centimeters long.
According to the Foundation, up until the beginning of the 20th century, hundreds of thousands of allis shad were still migrating up the Rhine and tributaries in order to reproduce.
At that time they were also offered in inns. However, due to overfishing, water pollution, and the expansion of the Rhine and its tributaries, they disappeared by the middle of the last century, and according to Scharbert even earlier in the Sieg.
