News

Crayfish Reintroduction Project in the Koblenz City Forest

In the spring, we set out early in the morning together with our partners from Schleswig-Holstein to collect the stone crayfish from the mating pond near Koblenz. To do this, we first slowly drained the water from the pond and then waited until the first stone crayfish ventured out of their hiding places. In fact, we managed to recover the majority of the stone crayfish, some of which were females carrying fertilized eggs. The eggs from the captured females were carefully removed from their swimmerets using tweezers and transferred to incubation boxes for transport. Both the females and the males were then returned to the donor water body. The eggs, in turn, were transferred to incubators for hatching. Now we must wait until the juvenile stone crayfish hatch, grow into summer juveniles, and can then be released into suitable waters. Stay tuned to see how the journey of our stone crayfish continues!

Stone Crayfish Reintroduction Project in the Koblenz City Forest

Since the native stone crayfish (Austropotambius torrentium) is threatened with extinction both across Europe and locally, a project has been underway for ten years in the Koblenz City Forest to breed stone crayfish for species conservation. Starting this year, our working group is also providing scientific support for this project. After the mating pond was cleaned and filled with water in early fall, our colleagues set out to search for suitable parent animals in the donor water. This search took place over several days and began at dusk. After successfully collecting males and females in a 1:2 ratio, they were placed in the mating pond to mate. Now it’s up to the animals to successfully mate over the winter! In the spring, the stone crayfish will then be removed from the pond and returned to the donor water. Before that, however, the fertilized eggs will be stripped from the females so they can be incubated under controlled conditions. But more on that next year!