Beavers are known for felling trees and building extraordinary dams, but did you know you may not know these dams play a significant role on the land and wildlife around them?
How do beaver dams affect their environment? Do they create positive or negative impacts? Or, what’s worse, what would happen if beavers were to disappear?
What is the purpose of beaver dams?
Beavers don’t build dams as homes. Although dams do play a large role in a beaver’s home environment, not in the way you might expect.
Beavers don’t live in the dams that they build, instead, they build them to create ponds of deeper water. They then build a lodge in the centre of the water, making it more difficult for predators to reach them.
Beavers live in those lodges. The lodges have their foundations on the ground floor and extend levels upward, eventually building up to appear above the water. Like beaver dams, lodges are made from logs, rocks, and other natural materials like grasses and moss. Beavers create underwater tunnels leading to and from their dams and lodges. These tunnels provide them with the best chance of escaping danger.
What is the purpose of dams? Is it just to hold water in place? Do they serve any other functions?
Typically, beavers will create hollows and passages inside the dam, enabling them to come and go as they please. Sometimes, they even use dams to hide from predators.
In the case of a sudden storm, beavers will use their dams as temporary shelters. During the summer and fall, they will hide food stashes inside the dam.
The benefits of beaver dams
Beavers produce many beneficial effects on the environment. Including:
- Beaver dams create new wetland areas: by creating new pools of water, beaver dams promote a variety of new flora and fauna to the area. These ponds can also stop flooding by collecting a large amount of water and slowing down what is lost through runoff.
- Beaver dams allow woodland diversity: because a lot of species thrive around wetlands, beaver dams promote biodiversity in the ecosystem.
- Beaver dams filter water: as water drains through the filter-like weave of the dam, sediment and debris are drained out of the water. This leads to a source of purer water downstream from the dam.
- Beaver dams help protect the land from climate change: beaver dams help reduce erosion by storing more water and reducing runoff. The ponds they create can also store carbon, keeping it from being released into the air. As well, they promote the growth of vegetation.
What would happen without beavers?
Seeing as beavers have such a significant impact on the ecosystem they inhabit, the world would be a very different place without them. Some areas could become overcrowded with too many trees, as beavers would no longer be there to thin out the trees and create a new space for new trees. The most aggressive plants would overpopulate the area within a few seasons. This would lead to a lower diversity of various species. Some species that depend on beavers and their dams, such as many species of birds, would likely suffer endangerment and have to find ways to adapt to a different environment.