Beavers know better. They saved the Czech government $1 million!

Beavers saved the Czech government $1 million!

In 2018, the Czech government proposed a project to create a dam on a river southwest of Prague. The intention was to revive the local ecosystem and protect the species that inhabit the river. However, bureaucracy paralyzed the project, and a colony of beavers, who do not care about paperwork, got to work.

In this way, a group of eight beavers built the dam their own way. That is, they simply used stones, wood and mud. What began as a small pond became a wetland that continues to grow thanks to the work of these rodents. Apart from being hardworking, they are also smart, as they chose the best possible location for their architectural masterpiece.

What happened to the dam?

The story begins in 1925, in the Brdy region, about 40 miles (64 km) southwest of Prague. The Czech government gave this region to the military as a training area, and the military built a drainage system on the Klabava river. Eventually, the Czech government wanted to demolish it and replace it with a new dam to revive the ecosystem.

However, due to negotiations on the ground, permission difficulties and governmental red tape, the plan remained nothing more than that. The status of the project was idle for seven years. And then, after all the waiting, the paralyzed project was suddenly complete, and for free!

Because there were no labor or material costs, the beavers have saved the Czech government $1.2 million USD. The head of the Protected Landscape Area (PLA) in Brdy, Bohumil Fišer, stated:

The Military Forest Administration and the Vltava River Basin Authority were negotiating the project and addressing land ownership issues. The beavers got ahead of them, saving us 30 million Czech korunas. They built the dams without any project documentation and at no cost. We can already see a small pond and the surrounding wetland forming.

Beavers are masters of engineering

These animals may not have a master’s degree in engineering or architecture, but they don’t need to. That’s because beavers are born knowing how to build a dam. Many people consider these rodents hardworking animals and masters of engineering. In fact, this eight-member colony built a natural dam in the perfect spot. And they’re still working to create more wetlands.

According to Jaroslav Obermajer, head of the Central Bohemia office of the Czech Nature and Landscape Protection Agency:

Beavers always know best. The locations where dams are built are always perfectly chosen; even better than what we designed on paper.

Why do beavers build natural dams?

Beavers act on instinct. Dam-building gives them a home with underwater entrances only, where they can be safe from land predators, such as wolves or bears. They both live and store food inside the dams.

Some people consider these animals a nuisance, as they gnaw on trees and plants for wood and can change the environment quickly. However, they are also capable of returning fresh water to areas that would otherwise have been deserted. They expand wetland ecosystems to the benefit of other creatures. Crayfish, frogs and many other species thrive in these wetlands.

These ecosystem engineers keep water in pools with three simple materials: wood, mud and stones. They place stones at the base of the dams and then add tree trunks and branches. The mud acts as cement and settles the construction.

What benefits do these natural dams produce?

These natural dams are so well built they can last for many years, allowing the surrounding ecosystem to flourish. Here are a few ways they benefit the environment.

Carbon capture. Beaver dams encourage plant growth and peat formation, which traps carbon, preventing it from being released into the air. This helps mitigate against climate change.

Water purification. Beaver dams can filter water almost twice as efficiently as human-built treatment plants.

Flood prevention. Beaver dams help to control runoff from heavy rain, thus reducing the risk of flash flooding.

Drought mitigation. These dams retain water in the soil, keeping the area moist. In addition, this can help protect areas against wildfire.

Beavers in the world

As you might expect, a moist area is less likely to burn. So, beaver dams can also help limit forest fires. For example, in 2018, a fire devastated a large swath of Idaho. However, the valleys the beavers inhabited remained lush, moist and green.

Scientists have also discovered that beaver ponds can reduce the effect of heavy metals at a rate two to four times greater than a riffle reach (a fast-flowing section of stream with a rocky bed).

California recognized the environmental benefits of beavers and launched a beaver-based restoration program in 2023. The Europeans did the same with the Eurasian beaver. Hunting nearly drove this species to extinction. But thanks to recent conservation efforts, beavers have been successfully reintroduced to several areas, including the Czech Republic.

Gerhard Schwab, beaver manager for the southern part of Bavaria for the Federal Nature Conservation Association, returned delighted from a field study of beaver habitats and enthusiastically announced the discovery of a valley in Belgium filled with newly formed ponds and streams. This is a clear example of the beaver’s ability to transform its environment. It seems that we still have a lot to learn from these natural engineers!