Against the silent dying in Isar and Loisach: environmentalists start project
Created: 08/19/2022, 06:06
By: Dominik Stallein
A heart for fish: Members of the Wolfratshausen district fishing association place grayling in the Isar.
© Private
Fish are suffering massively from climate change.
More and more stocks are disappearing.
Two associations want to keep the native animals in Isar and Loisach.
Wolfratshausen - It is a silent death: fish and amphibians disappear silently.
"They don't have the same lobby as other animal species," says Lorenz Demmel, manager of the sewage treatment plant in Weidach.
Together with the Wolfratshausen District Fishing Association, the Isar-Loisach Group Wastewater Association therefore started a nature conservation project three years ago.
According to Demmel, “sustainable nature and water protection is very important to the protagonists.
Against the silent dying in Isar and Loisach: environmentalists start project
In order for the small, trout-like graylings that live in the Isar and Loisach to survive, "a very good to good water quality" is a basic requirement.
Climate change is causing problems: "Heat waves cause the water levels in rivers and streams to fall further, which significantly reduces the habitats and places where fish can retreat," explains the head of the sewage treatment plant.
This makes it easier for predators such as otters, cormorants or goosanders to capture large numbers of fish, which has a noticeable impact on the population of the animals in running water.
Many fish are eaten: the stocks are declining in the Isar and Loisach
An otter would need "between 400 and 900 grams of food per day", a cormorant eats about 500 grams of fish per day.
"In combination, all three predators can cause a decline in the population in the trout region in the long term," Demmel fears.
In Wolfratshausen and the surrounding area: fishermen and the waste water association settle new fish
Native fish species are therefore regularly settled in the Isar and Loisach in order to secure the stocks in the long term - recently, some grayling were introduced.
The animal rights activists keep an eye on the reproduction rates of the individual species – including amphibians.
They also suffer from the heat.
Demmel: "A bird can move on and switch to a different habitat - in extreme heat, an amphibian only has its gum to hopefully sit out the extremes unscathed."
Only a few days ago, fishing clubs in the region sounded the alarm.
The summer will be "absolutely critical" for the survival of the local fish.
