Nature, 16.04.2024

We are now finding beavers in sewage treatment plants and in the sewerage system

The Federal Council wants to allow beavers to be shot. Jürg Zinggeler, hunting officer (Adjunkt Jagd) for the canton of Zurich, explains why beavers lead to conflicts. And how expensive the damage caused by beavers is every year.

Anna Kappeler
What's the problem with beavers? They are biodiversity machines, aren’t they?
Jürg Zinggeler
Absolutely. The beaver provides biodiversity for free - something that would otherwise cost a lot of money. But beavers are now spreading across our densely populated landscape, especially on the Central Plateau. And this leads to conflicts.

Which ones specifically?
The beaver builds dams. In streams, some of which have been dramatically straightened, this quickly leads to a backwater situation in the watercourses and drainage systems, which can then lead to flooding of agricultural crops. The beaver also likes to dig. The access to their burrows are always underwater. This can cause farm tracks along watercourses to collapse or even jeopardise cantonal roads.

When the Hunting Act (Jagdgesetz) was voted on in the autumn of 2020, beavers were still protected. But people should now be allowed to shoot them. Has the animal population multiplied so much in these three and a half years?
I can't confirm that for the last three years. What is clear is that the beaver population has increased. The last national monitoring programme for Switzerland in 2022 shows that the beaver population has developed fantastically over the last 20 years. According to the Federal Office for the Environment (FOEN - Bundesamt für Umwelt, Bafu), there are now around 4,900 beavers living in Switzerland. And the beaver population is three times larger than in 2008. Let me put it this way: the beaver colonisation has been a success. Nature conservation has been a success. One problem is, however, that the optimal habitats are already largely occupied, and the beaver thereby has to move into sub-optimal habitats. We are now finding beavers in sewage treatment plants and in the sewerage system.

And they clog these up?
Yes, and we then have to intervene. But we do this pragmatically.

"The beaver population has developed marvellously over the last 20 years," says Jürg Zinggeler, the Canton of Zurich's hunting officer. Photo: Christian Beutler

In other words?
We first try to drive the beaver away, and to prevent it from resettling in these particularly sensitive areas by means of structural measures.

And if that doesn't work, the last option is to shoot them?
No, this option is not envisaged under the current legislation.

Beavers have been protected until now. But the Federal Council (Bundesrat) now wants to be able to shoot them. Are they right in this?
I can't comment on this due to the current consultation process.

How much compensation does the canton pay for beaver damage each year?
The canton is liable to pay compensation for damage caused by wild animals to forests, agricultural crops and livestock. Specifically, if the beaver floods a field due to its damming activity and the farmer suffers a loss of yield, this will be compensated. Damage to infrastructure facilities, on the other hand, is not compensated. Or at least not yet, I have to clarify. This is set to change with the new Hunting Ordinance.

So it will be significantly more expensive then?
We are currently budgeting for that, so I can't say anything about that yet.

Can you give us a figure for beaver damage?
Beavers caused a good CHF 15,000 worth of damage to agricultural crops in the canton of Zurich in 2023. Compared to the total amount of damage caused by wild animals in the canton of Zurich, at around CHF 450,000, that's not very much. Wild boars alone caused damage totalling around CHF 300,000.