Something gnawed your oak tree? Sink hole in your road? How Zurich’s beaver hotline is reassuring residents

As the number of the semi-aquatic creatures soars so can tensions. But the Swiss have a tried and tested system to calm the neighbours and restore harmony

I hate beavers," a woman tells the beaver hotline. Forty years ago she planted an oak tree in a small town in southern Zurich - now at the frontier of beaver expansion - and it has just been felled: gnawed by the large, semi-aquatic rodents as they enter their seasonal home-improvement mode.

The caller is one of 10 new people getting in touch each week at this time of year. Beavers, nature's great engineers, can unleash mayhem during winter as they renovate their lodges and build up their dams. For people, this can mean flooding, sinkholes appearing in roads and trees being felled. A single incident can clock up 70,000 Swiss francs (65,000) in damages.