Beavers build dams for the same reason that birds build nests. Their species has developed this behavior to support the rearing of young. By extension, this protects the species as a whole. There is a difference between bird nests and beaver dams, however. These dams change entire ecosystems. They are so crucial to so many other species that beavers are well known as a keystone species. This means that their presence in an area is a significant cause of habitat change that affects plant and animal life. In particular, beavers create and protect wetlands.
What’s so important about wetlands?
Wetlands used to be considered nothing but a nuisance that needed to be drained. Diseases like malaria can be common around wetlands, and this needs to be considered. As far as wildlife is concerned, wetlands are essential. Waterfowl and amphibians rely on wetlands almost exclusively. These are only a fraction of the animals that depend upon wetlands. When beavers move into an area and build their dam, they change the water flow and create ponds. This requires some species to move to drier environments, but it also encourages multiple other creatures to find shelter and food within the dam system. Wetlands also serve an important watershed purpose. When flooding occurs, the wetlands give the excess water someplace to go. The animals that live in the area can adapt to this and restore the habitat in a short time.
Beavers can cause problems, too
With all this information about protecting wetlands, how can beaver dams be a problem? The fact is, beavers have no interest in the existing ecosystem that they alter in such significant ways. This includes forests, meadows, crop fields, housing areas, and more. Building one beaver dam can create a pond that causes flooding for an extensive area behind the dam. This can undermine bridges, homes, roads, and more. Beavers don’t understand that a rare tree needs protection. They only know they need to chew through it and drag it to their dam. They have even brought down utility poles in the past. When they don’t target a utility pole directly, their felled trees can land on the nearby wires and create a headache for local power companies. Appreciating the beaver is a complicated business.
We can still appreciate the beaver
Beavers are one of Nature’s workmen. The beaver sets into motion natural changes to an existing ecosystem. These enrich the soil and provide living space for water-dependent species. They create a space where the run-off from heavy rainfall will flow in a controlled manner. They are like a watery version of a naturally occurring forest fire. Forest fires change a habitat in dramatic ways. Some species depend on this to thrive in the aftermath of a fire. The same principle applies to beaver dams. They provide the change that allows other species to thrive.
