Beavers are amazing animals. They are one of the few animals in nature that have the ability to change (modify) their environment.
The beaver is mainly distributed in Europe. It is a semi-aquatic mammal belonging to the genus Beaver in the family Beaveridae of the order Rodent.
Every year during the dry season, people living near beaver habitats can always see such an interesting sight - a fallen tree pressing down on a beaver.
beaver killed by tree
In the 1980s, Norwegian ecologist Lars Wilsson and his colleagues came across an interesting thing when they went to Norway to observe the ecological environment in the wild.
They found the body of a beaver under a fallen aspen tree. Moreover, there are traces of rodent bites on the roots of this fallen aspen. In this scene, it seems that a hapless beaver was unfortunately hit by a fallen tree, and then died.
Before this, many local people said they had seen beavers killed or crushed by trees in the wild. At first people didn't know the reason, and for a while there were different opinions. Some even say that other beavers designed to kill their own kind.
As a scientist, Wilson naturally does not listen to rumors. He then observed in the wild many times, and visited various parts of Norway to sort out the incidents of beavers killed by trees. He believed that the beaver was killed by the tree purely by itself.
According to Lars Wilson's observation and sorting, he found that beavers like to "cut down trees" very much, and use their mouths to gnaw more than 400 trees a year, which is simply the bald head of the animal kingdom.
Thanks to their pair of front teeth, they can gnaw through trees up to 30 cm in diameter. But in the process of gnawing trees, beavers face a problem. That is, they cannot control the direction in which the tree falls, so it is easy to kill themselves.
Unlike humans, beavers will let trees fall in the direction they want by controlling fractures. They just gnawed and circled around the trees, with no obvious selection strategy.
So beavers can't tell when a tree will fall and in which direction. The result is obvious, many beavers will be hit by falling trees. If you are lucky, you may just be held down, and you will be able to come out by yourself after struggling for a while;
But even when life is at risk, beavers spend their lives chopping down trees. Why do they never give up? Below, we will explain slowly.
Timid and fearful, the beaver with very weak self-protection ability
As mentioned earlier, the beaver is a small animal that likes to inhabit the banks of forests and rivers in the cold temperate and subarctic zones. They are good at swimming and diving. They mainly feed on the twigs, bark and roots of plants. They are domestic animals.
They also secrete some oil, which is used for waterproofing. When it's free, the beaver "rubs" itself, essentially smearing the oil evenly on itself.
Although the beaver's forelimbs have sharp claws, the hind legs are stubby and powerful. But they are very timid, and their ability to protect themselves is extremely weak. Almost all carnivores are their natural enemies.
After finding a natural enemy, the beaver will quickly dive into the water and rely on its swimming talent to avoid the enemy. In an emergency, beavers can also dive. Under normal circumstances, they can dive for 12 minutes, which is enough time for them to escape.
But rather than fleeing, the beaver prefers to build a safe nest, so that it can avoid the pursuit of predators at any time. Trees, then, are the "building materials" they use to build their nests.
In addition, the reason why beavers "cut down trees" is related to their physiology.
Like most rodents, the beaver's four front teeth are constantly growing. So beavers need to grind their teeth, and gnawing on trees is how they grind their teeth. A lot of gnawed trees seemed like a waste not to do something about it, so the beaver took the trees to build a house and dam for themselves.
Beavers build dams to store water and protect their dens
In the heart of the timid beaver, only the den is the real safe place. Therefore, there must be ponds around the place where they choose to nest. The beaver then builds a foundation on the dry ground with wood, branches, soil, moss and water plants.
Beavers are "master architects", and even scientists believe they have "design blueprints" in their brains. From the outside, the beaver's lair looks like a pile of wood piled up randomly. But there are many rooms in the nest, and different rooms have different functions: eating, sleeping, breeding, etc., and even a special drying room.
To protect the safety of their dens, beavers usually open their burrows under the surface of the water, so that predators who can't dive can't get in at all. But sometimes, the water is not deep enough or the dry season arrives, and the mouth of the nest will be exposed.
To keep the mouth of the hole submerged, beavers evolved the ability to build "dams". After they gnaw down trees, they use water flow to transport the wood, and pile up a large number of trees, stones and sediment to form a "beaver dam" to block the water flow.
The presence of "beaver dams" can raise the water level and block the entrance to the nest. At the same time, beavers will build or remove "dams" according to the needs of the situation to control the water level at a suitable height.
In Alberta, Canada, a beaver family built a dam with a length of 850 meters, which is the longest "beaver dam" in the world. Scientists say it was built in 1975 and is still growing, with the potential to exceed 1,000 meters.
Although building dykes is a pain in the ass, a beaver usually takes years to complete and smashes itself to death while gathering wood. But building and protecting the den is the most important thing in a beaver's life, because the den is where the beavers have lived for generations.
Therefore, even if they are crushed to death, beavers will tirelessly gnaw trees. This is very similar to us humans, who carry heavy mortgages in order to have a stable home. Also, beavers clearly need a "house" more than we humans do.
Postscript: The merits and demerits of beaver
If there is no suitable environment around, the beaver will build it by itself. Therefore, where they live, there is basically a pond or wetland.
The existence of wetlands can increase species diversity, which is beneficial to the local ecological environment. At present, some areas in Canada have been specially cultivating beavers; or guiding beavers to build "beaver dams" in designated locations to improve the environment.
But in the same way, the dams built by beavers will block some migratory fish; at the same time, the dams are also at risk of collapse, especially in the rainy season, and the collapsed "beaver dams" may cause a small flood peak.
In addition, beavers build dams and gnaw trees wantonly, which is also a small damage to the ecological environment.