Science — environmental-science

Fish in Lake Carola Dresden show signs of massive death, indicating a decline in their population.

Dead fish, predominantly bream, are found floating on their backs in a sizeable garden pond. Investigations into the water have commenced following this mass fish death incident.

, and Administrator

2025 September 17 . 10:32 AM

2 min read

Lake Carola Dresden's fish population is perishing, facing an untimely demise

Fish in Lake Carola Dresden show signs of massive death, indicating a decline in their population.

In recent weeks, two fish kills have been reported in Germany, raising concerns about the health of local aquatic ecosystems.

On Tuesday, a large number of bream fish were found dead in the Hörsel river in Thuringia, with the exact cause of the fish kill remaining a mystery. The dead fish were discovered on Tuesday morning, and the Environmental Institute took a water sample on the same day for analysis. The final results from the water samples are expected by Thursday.

Meanwhile, in Dresden, approximately 70 dead bream were fished out of the Carolasee in the Großer Garten on September 9, 2025. The first dead fish were discovered on Monday. The investigation into the cause of the fish die-off in the Carolasee will be conducted by the Dresden Environmental Protection Agency.

The management of the State Palaces, Castles, and Gardens made the announcement about the dead bream in the Carolasee. Bream are scaled carp fish that are fished but do not have any particular economic importance as food fish.

Fishing in Saxony-Anhalt is under pressure due to the changing climate, and anglers are adapting to a new reality, facing challenges such as heat and fish kills. The fish population in the Oder is growing, but there is still a risk from gold alga.

A massive fish kill occurred at the Auensee in Leipzig on September 17, 2024, due to blue-green algae and lack of oxygen. Last year, UFZ Leipzig found another cause for a fish kill on the Oder.

The fish kill near Dresden on August 18, 2025, was caused by a defective sewer pipe, affecting only the bream. The fish kill in the Carolasee, however, remains a mystery, with the investigation ongoing.

As the causes of these fish kills are determined, efforts will be made to protect and preserve the local aquatic ecosystems and ensure the long-term health of the fish populations.