Flooding
Dams raise the water level and can flood lower-lying plots, drainage systems, paths or cellars.
Do not intervene.
The beaver, its habitat and its structures are protected by law. The first reflex is not to act on your own: it is to alert the right people.
In Switzerland, the Eurasian beaver is a species protected by federal law since 1962. This protection extends to the animal itself but also to its habitat: its burrows, lodges and dams may not be destroyed, moved or altered without authorization.
Good to know
Any intervention on the beaver or its structures without cantonal authorization — destroying a dam, filling in a burrow — exposes you to criminal prosecution.
If there is a problem, the right contact is the Police faune-nature inspector (the cantonal wildlife warden) or the Direction générale de l'environnement (DGE-BIODIV): they assess the situation and decide, if necessary, on authorized measures. In Vaud? Find my sector's coordinator (map of the nine districts, with phone numbers).
This page is not meant to teach you how to "resolve" conflicts on your own. It aims instead to help you understand conflict situations, put in place preventive measures that comply with the legal framework, and identify the people to contact when this becomes necessary.
Biodiversity: the engineer that recreates life.
Before talking about conflicts, let's recall the essential point: wherever it settles, the beaver rebuilds wetlands that had disappeared — and with them, a thriving biodiversity.
By raising the water level, the beaver transforms a simple watercourse into a mosaic of wetlands: oxbows, ponds, flooded meadows, standing dead wood. These habitats, among the richest and most threatened in Europe, once again become a refuge for hundreds of species — amphibians, dragonflies, waterbirds, fish, insects and rare plants.
This is not an impression: it is measured. A national research project led by the Federal Office for the Environment (FOEN) from 2020 to 2023 compared stretches shaped by the beaver with neighbouring control stretches — comparable watercourses, but without a beaver. Where the beaver is active, there are on average 2.6 times more species and 5.9 times more individuals. And when it can deploy its full potential — by flooding banks and adjacent land — the effect climbs to 6.5 times more species and 62 times more individuals. A landscape-scale meta-analysis (a synthesis of several studies) confirms the trend — see the key figures below.
Control stretch vs beaver stretch
Relative values — each measure compared to its control stretch (×1), both measures on the same scale.
The control (grey) is a reference point, not a result.
Number of species
Number of individuals
Full potential
×62
times more individuals than in a control stretch The maximum observed, when the beaver can flood the banks and adjacent land.
×6.5 times more species, in the same situation and on the same comparison.
Source: FOEN, 2025 — full reference.
≈ 4 900
beavers in Switzerland, across 1 402 territories (2022 census)
2 out of 3
territories cause no conflict at all
83 %
of cases: the number of animal species increases in the presence of the beaver — 79 % for plant species (meta-analysis)
These ponds provide concrete services to the whole area, well beyond the visible wildlife. Beaver ponds purify the water (up to 20 % less nitrates downstream, where wetlands form), recharge groundwater and retain water in the landscape — an asset against both droughts and floods — and act as carbon sinks: the Marthalen (ZH) wetland stores nearly 3 times more carbon than the forest it replaced. All revitalization that the beaver carries out free of charge, where technical works would be costly.
Changing perspective. Most of the “damage” attributed to the beaver is in fact the visible effect of a habitat regenerating itself. Well managed, its presence is an opportunity for nature — and conflicts, for their part, can be prevented and resolved.
87.5 %
of beaver territories are home to amphibians, compared with 25 % of control sites
231 t CO₂-eq/yr
stored on the 4 ha wetland at Marthalen
≈ 30 000 ha
with high potential for nature — compared with ≈ 15 000 ha prone to conflict: opportunities outweigh the risks
Figures for this section: FOEN, 2025 — full reference.
#StopBarbelés
A strand of barbed wire. Invisible to us, deadly to them.
An old strand of barbed wire forgotten at the water's edge is almost invisible — and dangerous for the beaver and all wildlife, which get injured or drown in it. BeaverWatch actively campaigns against barbed wire left in nature.
- Protects wildlife
- Prevents injuries and drownings
- Preserves our natural habitats
Removing one wire saves a life. Spotted one? Report it.
Report barbed wirePhoto · Pierre-Alain Marro
Understanding: where do conflicts come from?
The beaver is a water animal. Friction with human activities is concentrated in a narrow band along watercourses — where it lives, feeds and builds.
Let's say it from the outset: conflicts are a minority and are solvable. Two out of three beaver territories cause no damage at all. Its dams remain passable for fish — every species tested by the FOEN can move upstream past them — and, on a Swiss scale, compensation for damage amounts to only 30 000 to 80 000 CHF a year. What remains is a minority of situations that need to be understood and dealt with: that is the subject of the sections that follow.
The beaver spends nearly 90 % of its time within 30 m of the water. It is in this riparian strip — generally 10 to 20 m on either side of the streambed — that damage is concentrated. Knowing this pattern makes it possible to anticipate, rather than simply endure.
Damage to crops & trees
The beaver gnaws bankside trees and feeds on nearby crops (maize, beets, orchards).
Bank collapses
Burrow tunnels weaken banks and riverside paths, which can give way under the weight.
The dams: recognizing before acting.
Not all dams are the same. Identifying the type of structure is the first step: it determines the room for manoeuvre — and whether a cantonal decision is required.
Temporary
Function: trial impoundment, quickly built and often abandoned.
Clue: small, made of loose branches, little material, weak impoundment.
Management sometimes possible outside protected areas
Secondary
Function: stabilizes the water level upstream or downstream of the main dam.
Clue: reinforced structure, clear impoundment, present in a chain.
Cantonal decision required
Main
Function: creates and maintains the water depth vital to the colony.
Clue: long, massive, watertight, wide and lasting impoundment.
Cantonal decision requiredWhen a dam causes a problematic rise in water level, the first solution is not to destroy it — it would be rebuilt within a few nights — but to regulate the water level. Generic devices, such as a levelling pipe running through the dam, let a constant flow pass without triggering the animal's plugging instinct. Installing them is always a matter for consultation with the cantonal wildlife service.
Trees & crops: protecting what matters.
A few simple measures, placed in the right spot, are usually enough to put notable trees and crops out of reach — without harming the animal.
Wire-mesh sleeve for isolated trees
For a notable or fruit tree, a wire-mesh sleeve encircling the trunk is the most reliable protection. It must be at least 1.2 m high, kept clear of the trunk and firmly fixed to the ground.
Fencing: the right mesh, properly installed
For an orchard or a plot, a wire-mesh fence effectively stops the beaver — provided the right material is chosen. A steel mesh with tight openings (≈ 6 × 6 cm) is suitable; flexible netting, plastic mesh or mesh that is too wide must be avoided.
6 × 6 cm steel
approved
Chicken wire
to avoid
Plastic or wood
to avoid
10 cm mesh
to avoid
Installation matters as much as the material: the bottom of the mesh must be buried 30 to 40 cm deep (or folded outward) to stop the beaver digging underneath.
Photo · Christof Angst
Base buried, mesh taut
The mesh runs down into the ground: the beaver can neither pass underneath nor lift it.
Base not buried
Laid directly on the ground, the mesh is bypassed from underneath in a single night.
The underlying fix. Beyond one-off protective measures, favouring softwood on the banks — willows above all — gives the beaver a natural food cache within immediate reach. Well fed on the bank, it ventures much less often toward notable trees and crops.
Banks & burrows: stabilizing without evicting.
Burrows and drainage are the most discreet conflicts — but also the trickiest. Good site-management practices prevent collapse while still leaving room for the beaver.
Threatened banks and paths: buried mesh
The beaver digs its burrows into the bank; their tunnels can weaken the soil at the surface. Protection should not, however, be applied systematically to natural banks: it is justified when a concrete safety or functional issue is demonstrated and a less invasive solution is not sufficient. Before opting for buried mesh, it is therefore worth examining other options: relocating a path, widening the available space, reducing the bank's slope, adapting maintenance, protecting a targeted area or, in some cases, building an artificial burrow.
When mesh is needed, its effectiveness rests on a simple condition: being continuous and impossible to bypass. This requires a horizontal return at the top of the bank of at least 2 m, ideally 3 m, and an earth covering of at least 30 cm. Maintenance remains light to moderate: an inspection after floods, recent settling and earthworks, then occasional checks. If an occupied burrow is suspected or discovered, work is suspended in the area concerned and the competent cantonal authority is contacted before proceeding any further.
Safety — mesh size is not a detail. 15 cm mesh must be avoided: a beaver can get its head caught in it, become trapped and die. The maximum mesh size allowed is 10 × 10 cm, the recommended mesh size is 6 × 6 cm.
Targeted, properly sized and monitored protection remains preferable to extensive artificial hardening without a demonstrated need: it is a local measure, not a way to stop the beaver's activity. No price can be given here, however, as it depends on bank height, earthworks, access and work carried out in the water.
Safety point — bridle paths. Along a stretch with burrows, the ground of a path can give way under a horse's hoof, where a tunnel passes just below the surface. A concrete risk to report to municipalities and to the managers of riverside trails.
Drainage pipes: the anti-intrusion grille
The beaver perceives the sound of water in a pipe as a leak to be plugged: it may block it or move in. From a diameter of 250 mm upward, an anti-intrusion grille at the inlet solves the problem upstream.
Unprotected pipe
The inlet is blocked by the beaver: the water backs up and floods the area upstream.
Clear pipe
Protected at the inlet, the pipe stays clear and flow is maintained.
Many devices exist; few prove both effective and easy to maintain. From our field experience, fixed grilles are not satisfactory: they clog up, log jams and debris carried by the watercourse build up in them, and they have to be cleared out again and again. Yet they are not easy to dismantle, so every maintenance job becomes a major undertaking. This finding is BeaverWatch's own, drawn from our own worksites: it is field experience, not published data.
The two models below are the ones we install today. The device is chosen based on the pipe, with no particular brand preferred; its vertical bars are spaced no more than 15 cm apart. Be careful not to confuse the two measurements on this page: this 15 cm is a spacing between bars on a pipe grille, not a buried mesh opening. For mesh, 15 cm openings must on the contrary be avoided (a beaver can get its head caught in them) and the maximum allowed is 10 × 10 cm.
A beaver settles near me.
The steps to follow fit into four stages. The order matters: it is what guarantees an outcome that is legal, lasting and respectful of the animal.
- Do not take any action Do not touch the animal, its dams, burrows or lodges. Document the situation (photos, location) without intervening.
- Contact a Police faune-nature inspector or the DGE-BIODIV This is the official contact point: they guide, authorize and coordinate. No measure is decided without them. In the canton of Vaud: browse the DGE directory (contacts by area of responsibility, including the Police faune-nature inspectors).
- A specialist assesses the site The site is surveyed: type of structure, real scale of the conflict, possible measures. For any information in your area: find my sector's coordinator.
- Measures are decided — with authorization if necessary Water-level regulation, tree protection, bank management: the appropriate solution is implemented within the legal framework.
Prevention vs. enforcement
Prevention first — always. Exclusion (fencing, tree sleeves) and deterrence are applied before any damage occurs, without harming the animal.
Enforcement measures remain exceptional and strictly regulated: capture-and-relocation, and, only as an absolute last resort, culling — solely with federal authorization (FOEN), if prevention has failed, never during the rearing of young, and carried out by an official body.
Culling is neither a first resort nor a lasting solution: a cleared stretch is quickly recolonized.
Compensation for damage
Damage unquestionably caused by the beaver to crops and forests may be compensated — provided that reasonable preventive measures were taken beforehand. Fences that were actually installed must, moreover, be reported within 10 days.
Damage to agriculture and forestry is covered half by the Confederation, half by the canton, under Art. 13 of the Federal Act on Hunting and the Protection of Wild Mammals and Birds (LChP) and Art. 10 of the Ordinance on Hunting and the Protection of Wild Mammals and Birds (OChP). Each canton sets the threshold below which it does not pay compensation.
In the canton of Vaud, the process is handled by DGE-BIODIV and takes place in four steps:
- contact the regional Police faune-nature inspector to discuss prevention;
- fill in the declaration form, one form per affected crop plot;
- a claims assessor (taxateur) gets in touch to assess eligibility for compensation;
- DGE-BIODIV pays the compensation if eligibility is confirmed.
Damage or a conflict? Talk to someone about it.
On the map of the nine Vaud districts, each sector shows its coordinator and phone number. You can also report your observation: it feeds into the cantonal database and triggers, if needed, the intervention of a specialist.
Sources and BeaverWatch technical sheets
Content, diagrams and photos (field and aerial views) drawn from BeaverWatch's technical sheets and surveys — available from the association on request.
- Les barrages et leur fonction — typology and role of the structures.
- Technical sheet Barrages — construction phases.
- Technical sheet Terriers — protection and safety distances.
- Technical sheet Protection des berges contre le castor (version 1.0, August 2026) — buried mesh, sizing and maintenance.
- Technical sheet Grille anti-intrusion — pipe protection.
- Déprédations liées au castor — prevention, enforcement and compensation.
- Éviter et résoudre les conflits avec le castor — tree and crop protection.
Numerical data (Biodiversity section) — federal publication:
FOEN (2025). Le castor – un partenaire efficace pour des eaux vivantes. Biodiversité 2025. Federal Office for the Environment, Bern. Authors: C. Angst & C. Auberson (info fauna). Available in German and French. bafu.admin.ch/castor (new window)
Legal framework: the beaver is protected in Switzerland under the LChP. Any measure affecting the animal or its structures is subject to cantonal authority, and any culling to federal authorization (FOEN).