Environment: Oder disaster affects sturgeon reintroduction

environment
Or disaster affects sturgeon reintroduction

With the environmental catastrophe in the Oder, the reintroduction project for the Baltic sturgeon suffered a major setback. “But it’s not a total failure, because sturgeons are a very long-lived fish species that can live up to 100 years and can also survive poor environmental conditions,” said Jörn Gessner from the Leibniz Institute for Freshwater Ecology and Inland Fisheries (IGB) in Berlin of the German Press Agency. Since 2006 he has been coordinating the ongoing project in Brandenburg and Mecklenburg-West Pomerania.

Since the start of the project, 3.5 million mini sturgeons have been raised and then released into the Oder. The animals, which are then around 20 centimeters in size, migrate to the mouth of the river, the Oderhaff, where they continue to grow for two years until they swim into the Baltic Sea. When they reach sexual maturity after 15 to 20 years, they should return to the Oder to spawn. Gessner assumes that the sturgeons will actually return as soon as the river has regenerated and the animals find food and spawning grounds there. “We are currently experiencing a damper, but no stop to the project,” he said.

In a sturgeon breeding station in Friedrichsthal (Uckermark) in Brandenburg in the Lower Oder Valley National Park, a third of the 20,000 offspring died because contaminated Oder water flowed through the facility. The remaining specimens, three to five centimeters in size, were released during an emergency rescue in the national park’s polder waters, which currently have no connection to the border river. According to the National Park Administration, dead sturgeons measuring around 30 to 90 centimeters in size were also found when the fish died in the Oder, probably reared young animals from previous years.

dpa