The Eurasian beaver, Castor fiber, weighs 15-30 kg, its body length is 0.7-1 m, but its tail is ~ 30 cm long. There are approximately 82 000 beavers in Latvia.
The beaver is a vegetarian which subsists on barks, branches and water plants. It does not eat fish, frogs or snails.
It is sometimes called «an engineer of the animal kingdom» as beavers build complex dams, lodges and canals.
The dam provides deep slowly running water reservoir, where the beaver can construct its habitation safe from land predators and supply the construction materials by floating them on water. The main natural enemy for the beaver is the wolf and the lynx, but the young is threatened by the fox or the racoon dog.
The foundation of the dam can be made from sludge and stones. The beaver adds bushes and logs using mud, stones and wet plants as binder.
The dam is always higher than the level of water, and it is maintained and frequently repaired by several generations of beavers.
The beaver pond can occupy several hectares. The average length of the dam is 22.75 m, but they can also be up to 600 m long. The beaver is active during twilight and at night. If the beaver notices any danger, it slaps its tail against the water thus making warning signals for the others. If there is no danger, the beaver plunges in very quietly. In autumn the beaver is very active on the shore where it gnaws trees and their branches, pulls them into water and stores them for winter provisions.
Taking into consideration the big amount of beavers in Latvia, their number in each watercourse has to be evaluated separately.
