Predatory enemies, not enough nutrients, empty fishing nets: In order to save the population of whitefish, they may no longer be caught in Lake Constance for the next three years. A change is imminent for Lake Constance fishing, because the blue whitefish is their flagship.
However, the whitefish catches in 2022 were 89 percent below the average of the past ten years, as the International Conference of Representatives for Lake Constance Fisheries (IBKF) announced after the decision to ban fishing.
The situation of the whitefish is worrying. Young fish in particular were missing. The main reason for the sudden need for action is the spread of a former aquarium fish, the stickleback. It now accounts for around 90 percent of the fish in the open water of the inland waterways between Germany, Austria and Switzerland.
Sticklebacks and cormorants bother the whitefish
The stickleback is actually more at home near the shore, while the bluefish is an open water fish. According to the fisheries research center in Langenargen, this was not a problem until 2012. But years ago, the whitefish’s food competitor changed its behavior for unknown reasons and also migrated into the open water. Therefore, according to the IBKF, so-called stickleback management should also be examined. “An international cormorant management on Lake Constance to protect the fish stocks” is also necessary.
With tougher steps against the fish-eating migratory bird and further steps against stickleback and algae growth, a multi-year ban on fishing could have been avoided from the point of view of the 64 professional fishermen. “The ban on fishing for whitefish is the smallest factor in protecting the fish stocks in the lake,” said Elke Dilger, chairwoman of the Association of Baden Professional Fishermen. “Every day the exploding population of cormorants at the lake takes tons of fish out of the lake. Fish that we leave for the cormorants to eat.”
For more than 20 years, fishermen have been calling for the number of cormorants to be regulated – if in doubt, by shooting them. Conservationists object because the birds are protected by law. The fishermen are now demanding that the Baden-Württemberg state government, the Ministry of the Environment and the nature conservation associations must create “a feasible and effective cormorant management system” in the next five months. The close season for the whitefish could be implemented in five months.
Additional nets for catching other food fish
Because the whitefish nets are also used to catch other food fish such as roach, burbot, char and perch, additional net types should be permitted according to the IBKF. “In this way, the fishermen can continue to offer fresh fish from Lake Constance,” says a statement from the committee, in which each resident has an authorized representative. A ban on fishing for whitefish could only be decided unanimously. The decision was made at the annual IBKF conference in Ittingen, Switzerland.
The blue whitefish is considered to be the Lake Constance fish par excellence. The demand for the edible fish is particularly high among holidaymakers, which is why there has already been discussion about fish farming facilities on Lake Constance. Fishermen have been complaining about the low earnings situation for years.
